Portrait of Dr Dinkar Sharma

Dr Dinkar Sharma

Reader in Psychology
Director of Education

About

Dinkar is a Reader in Psychology and Director of Education.

Research interests

Dinkar's main areas of current research are:

  • EMOTION. Using the Stroop task and Posner's cueing paradigm I have looked at various factors that moderate the pattern of disruption from emotional stimuli. The major issue here is the role of emotional interference in cognitive control. Our hypothesis is that emotional interference is the result of systems that disengage attention from the task for a brief period of time. This has been implemented in a recent model (see Wyble, Sharma, & Bowman, 2008).
  • ADDICTION: I am interested in the processing of addiction (in particular, alcohol and smoking) related stimuli. This research aims to develop objective measures, test cognitive models, and investigate techniques that can be used to reduce the impact of these stimuli.
  • ATTENTION: Testing cognitive models of selective attention (eg connectionists, translation models) by varying task set (eg mindfulness meditation), properties of the stimulus as well as modality of the response.

Dinkar would welcome applications from potential doctoral students in these areas.  Anyone interested in practicing meditation please see http://www.meditationkent.org.uk/

Supervision

Current research students

Past research students

  • Dr Fatma Ateş (2018) Undertstanding spontaneous recognition: The role of working memory, emotions and mood
  • Dr Tom Kupfer (2017) Disease avoidance and other functions of disgust (2nd supervisor)
  • Dr Sarah Hotham (2013) Attention and eating behaviour: The role of cognitive control
  • Dr Sharon Money (2010) Intentional and incidental Associative-Learning and the Emotional Stroop test
  • Dr James Cane (2009) Smoking attentional bias: The role of automaticity, affect and cognitive control
  • Dr Robert Booth (2009) Attentional Control Theory & Stroop interference: Selective attention deteriorates under stress
  • Dr Ana Fernandez (2007) An investigation into how emotion orients attention
  • Dr Jason Tipples (1999) Deciding emotional meaning: A preattentive process?

Professional

Grants and Awards

2012-2014Hopthrow T, Abrams D., & Sharma D.
DSTL
DSTL Network
£77,763
2010Sharma D. & Leader T. 
British Academy 
Charting the rise in anxious mood since 1969: a meta-analysis of trait anxiety across time and nations.
£7,500
2010Sharma D.
University of Kent Faculty of Social Sciences 
The role of emotion in new word learning.
£990
2006Hamilton-West K. & Sharma D.
British Academy
Physiological Responses to Positive Emotions: Testing the undoing effect.
£1,541
2004-06Sharma D. & Brown R.
Economic and Social Research Council
The social regulation of cognitive function
£42,873
2003-06Sharma D. 
External collaborator on a French Ministry of Research grant to Huguet P. "Comportement et cognition : Études expérimentales de l'influence du contexte sur le traitement de l'information chez l'homme." ("Behaviour and cognition: Experimental studies of the influence of contextual factors on information processing in humans").
The social regulation of cognitive functioning
£25,000
1996-97D Sharma
University of Kent Small grant
Developing an objective measure of sensitivity to alcohol related stimuli.
£1,876


Professional memberships

Publications

Showing 50 of 105 total publications in the Kent Academic Repository. View all publications.

Article

  • Youngs, M., Lee, S., Mireku, M., Sharma, D., & Kramer, R. (2020). Mindfulness Meditation Improves Visual Short-Term Memory. Psychological Reports. doi:10.1177/0033294120926670
    Research into the effects of mindfulness meditation on behavioral outcomes has received much interest in recent years, with benefits for both short-term memory and working memory identified. However, little research has considered the potential effects of brief mindfulness meditation interventions or the nature of any benefits for visual short-term memory. Here, we investigate the effect of a single, 8-minute mindfulness meditation intervention, presented via audio recording, on a short-term memory task for faces. In comparison with two control groups (listening to an audiobook or simply passing the time however they wished), our mindfulness meditation participants showed greater increases in visual short-term memory capacity from pre- to post-intervention. In addition, only mindfulness meditation resulted in significant increases in performance. In conclusion, a single, brief mindfulness meditation intervention led to improvements in visual short-term memory capacity for faces, with important implications regarding the minimum intervention necessary to produce measurable changes in short-term memory tasks.
  • Pappous, A., Mohammed, W., & Sharma, D. (2020). Physiotherapists’ experiences with a four-week mindfulness-based stress reduction program. European Journal of Physiotherapy. doi:10.1080/21679169.2020.1745272
    Objective: The study sought to gather the perceptions and experiences of a group of physiotherapists who took part in mindfulness-based stress reduction program (MBSR). Methods: Semi-structured interviews were conducted with eight physiotherapists who took part in a four-week formal and self-directed mindfulness meditation program. The data collected were analysed by implementing a thematic analysis. Results: Themes were identified in relation to perceived health benefits (stress reduction and increased attentiveness), the perceived impact of the MBSR on their professional practice and the perceived difficulties in practicing mindfulness. Conclusion: The data from this study offer qualitative evidence that mindfulness practise can become an important element in a physiotherapists’ stress reduction toolkit, by helping them deal with the challenges of their professional practise. The main difficulties encountered with the program were related to the feelings of sleepiness that MBSR induced in them in the beginning. The participants also reported that the long duration of the sessions was another obstacle, suggesting that a brief form of meditation would be preferable and more convenient.
  • Parris, B., Sharma, D., Weekes, B., Momenian, M., Augustinova, M., & Ferrand, L. (2019). Response Modality and the Stroop Task: Are there phonological Stroop effects with manual responses?. Experimental Psychology, 66, 361-367. doi:doi:10.1027/1618-3169/a000459
    A long-standing debate in the Stroop literature concerns whether the way we respond to the color dimension determines how we process the irrelevant dimension, or whether word processing is purely stimulus driven. Models and findings in the Stroop literature differ in their predictions about how response modes (e.g., responding manually vs. vocally) affect how the irrelevant word is processed (i.e., phonologically, semantically) and the interference and facilitation that results, with some predicting qualitatively different Stroop effects. Here, we investigated whether response mode modifies phonological facilitation produced by the irrelevant word. In a fully within-subject design, we sought evidence for the use of a serial print-to-speech prelexical phonological processing route when using manual and vocal responses by testing for facilitating effects of phonological overlap between the irrelevant word and the color name at the initial and final phoneme positions. The results showed phoneme overlap leads to facilitation with both response modes, a result that is inconsistent with qualitative differences between the two response modes.
  • Booth, R., & Sharma, D. (2019). Attentional Control and Estimation of the Probability of Positive and Negative Events. Cognition and Emotion, 1-15. doi:10.1080/02699931.2019.1657382
    People high in negative affect tend to think negative events are more likely than positive events (“probability bias”). Studies have found that weak attentional control exaggerates another negative affect-related cognitive bias – attentional bias – but it is not clear why this might be. We therefore wanted to know whether weak attentional control would be related to probability bias too. Four studies, with predominantly female student samples (N = 857), revealed correlations of around −.38 between attentional control and probability bias. This remained significant when trait anxiety and depression were controlled; there were no interactions between attentional control and negative affect. Studies 3 and 4 found that attentional control’s relationship with probability bias was partly mediated by emotion regulation ability. These results suggest attentional control is important for regulating affect-related cognitive biases, and for emotion regulation in general. Furthermore, because cognitive biases are thought to be important for maintaining emotional disorders, these results are also consistent with weak attentional control being a risk factor for these disorders.
  • Hsieh, C., & Sharma, D. (2019). Priming Emotional Salience Reveals the Role of Episodic Memory and Task Conflict in the Non-color Word Stroop Task. Frontier in Psychology: Cognition. doi:10.3389/fpsyg.2019.01826
    Previous research attempted to account for the emotional Stroop effect based on connectionist models of the Stroop task that implicate conflict in the output layer as the underlying mechanism (e.g., Williams et al., 1996). Based on Kalanthroff et al.’s (2015) proactive-control/task-conflict (PC-TC) model, our study argues that the interference from non-color words (neutral and negative words) is due to task conflict. Using a study-test procedure 120 participants (59 high and 61 low trait anxiety) studied negative and neutral control words prior to being tested on a color responding task that included studied and unstudied words. The results for the low anxiety group show no emotional Stroop effect, but do demonstrate the slowdown in response latencies to a block of studied and unstudied words compared to a block of unstudied words. In contrast, the high anxiety group shows (a) an emotional Stroop effect but only for studied negative words and (b) a reversed sequential modulation in which studied negative words slowed down the color-responding of studied negative words on the next trial. We consider how these findings can be incorporated into the PC-TC model and suggest the interacting role of trait anxiety, episodic memory, and emotional salience driving attention that is based on task conflict.
  • Booth, R., Sharma, D., Dawood, F., Doğan, M., Emam, H., Gönenç, S., Kula, N., Mazıcı, B., Saraçyakupoğlu, A., & Shahzad, A. (2019). A relationship between weak attentional control and cognitive distortions, explained by negative affect. PLOS ONE, 14, e0215399. doi:10.1371/journal.pone.0215399
    People high in negative affect (anxiety or depression) show cognitive distortions, specific thinking errors which contribute to the maintenance of their condition. It is thought that weak attentional control is a risk factor for negative affect and emotional disorders, because weak attentional control exaggerates the expression of attentional bias, another cognitive feature of emotional disorders. We wondered whether weak attentional control might similarly exaggerate the expression of cognitive distortions. In two samples of students from Turkey and the UK, we found that weak attentional control was indeed related to cognitive distortions, but this relationship was explained by both variables’ relationships with negative affect. This suggests that weak attentional control, while related to negative affect, does not necessarily exaggerate all of its cognitive features. There seems to be a limit on the affective consequences of poor attentional control, which may limit its clinical usefulness as a risk factor for emotional disorders.
  • Mohammed, W., Pappous, A., & Sharma, D. (2018). Effect of Mindfulness Based Stress Reduction (MBSR) in Increasing Pain Tolerance and Improving the Mental Health of Injured Athletes. Frontiers in Psychology, 9. doi:10.3389/fpsyg.2018.00722
    Literature indicates that injured athletes face both physical and psychological distress
    after they have been injured. In this study, a Mindfulness Based Stress Reduction
    (MBSR) was utilised as an intervention for use during the period of recovery with injured
    athletes and, to the best of our knowledge, this is the first study using MBSR as an
    intervention for this purpose.
    Objective: The aim of this research was to investigate the role of MBSR practise in
    reducing the perception of pain and decreasing anxiety/stress, as well as increasing
    pain tolerance and mindfulness. An additional aim was to increase positive mood and
    decrease negative mood in injured athletes.
    Methods: The participants comprised of twenty athletes (male = 14; female = 6; age
    range = 21–36 years) who had severe injuries, preventing their participation in sport
    for more than 3 months. Prior to their injury, the participants had trained regularly
    with their University teams and participated in official university championships. Both
    groups followed their normal physiotherapy treatment, but in addition, the intervention
    group practised mindfulness meditation for 8 weeks (one 90-min session/week). A Cold
    Pressor Test (CPT) was used to assess pain tolerance. In contrast, the perception of
    pain was measured using a Visual Analogue Scale. Other measurements used were
    the Mindful Attention Awareness Scale (MAAS), Depression Anxiety and Stress Scale
    (DASS), and Profile of Mood States (POMS).
    Results: Our results demonstrated an increase in pain tolerance for the intervention
    group and an increase in mindful awareness for injured athletes. Moreover, our
    findings observed a promising change in positive mood for both groups. Regarding
    the Stress/Anxiety scores, our findings showed a notable decrease across sessions;
    however, no significant changes were observed in other main and interaction effects in
    both groups.
    Conclusion: Injured athletes can benefit from using mindfulness as part of the sport
    rehabilitation process to increase their pain tolerance and awareness. Further research
    is required to assess whether increasing pain tolerance could help in the therapeutic
    process.
  • Mohammed, W., Pappous, A., Muthumayandi, K., & Sharma, D. (2018). The Effect of Mindfulness Meditation on Therapists’ Body-Awareness and Burnout in Different Forms of Practice. European Journal of Physiotherapy. doi:10.1080/21679169.2018.1452980
    Objectives: The main aim of this study was to explore if mindfulness increase therapists’ (physiotherapists and sport therapists) body-awareness and if it can have an effect on reducing their burnout in the workplace. Additionally it was intended to gather evidence about which methods (face-to-face groups FFGs with an instructor or self-directed group SDG) of mindfulness meditation program (MMP) were more effective with therapists.
    Methods: Online tools such as websites, skype and online surveys were used with participants as part of the methodology. Seven measurements were used to assess the effect of mindfulness meditation on therapists after 4 week of formal and informal practise.
    Results: Our results showed that attention regulation, self-regulation and trusting in FFGs had significant improvement in pre and post meditation practise. Findings showed significant differences between groups for the FFGs. Particularly, our findings indicated a clear improvement in the acting with awareness, positive affect of mindfulness, emotional awareness and reduction in burnout. However, no changes were observed in stress.
    Conclusions: MMP has positively affected therapists, specifically in the FFGs. Therapists in the FFGs gained benefits from mindfulness to improve their body-awareness and less level of burnout at workplace. The benefits of the mindfulness programme were more significant when delivered in a face-to-face programme rather than in a self –directed way.
  • Dumay, N., Sharma, D., Kellan, N., & Abdelrahim, S. (2018). Setting the alarm: Word emotional attributes require consolidation to be operational. Emotion, 18, 1078-1096. doi:10.1037/emo0000382
    Demonstrations of emotional Stroop in conditioned made-up words are flawed due to the lack of task ensuring similar word encoding across conditions. Here, participants were trained on associations between made-up words (e.g., 'drott') and pictures with an alarming or neutral content (e.g., 'a dead sheep' versus 'a munching cow') in a situation that required attention to both ends of each association. To test whether word emotional attributes need to consolidate before they can hijack attention, one set of associations was learnt seven days before the test, whereas the other set was learnt either six hours or immediately before the test. The novel words' ability to evoke their emotional attributes was assessed using both Stroop and an auditory analogue called pause detection. Matching words and pictures was harder for alarming associations. However, similar learning rate and forgetting at seven days were observed for both types of associations. Pause detection revealed no emotion effect for same-day (i.e., unconsolidated) associations, but robust interference for seven-day-old (i.e., consolidated) alarming associations. Attention capture was found in the emotional Stroop as well, though only when trial n-1 referred to a same-day association. This task also showed stronger response repetition priming (independently of emotion) when trials n and n-1 both tapped into seven-day-old associations. Word emotional attributes hence take between six hours and seven days to be operational. Moreover, age interactions between consecutive trials can be used to gauge implicitly the indirect (relational) episodic associations that develop in the meantime between the memories of individual items.
  • Gonidis, L., & Sharma, D. (2017). Internet and Facebook related images affect the perception of time. Journal of Applied Social Psychology, 47, 224-231. doi:10.1111/jasp.12429
    Even though there is a wealth of research on addiction and implicit measures, the effects of addiction on time perception are still unclear. Internal clock models separate the effects of attention and arousal which could have important implications for addiction research. The present study investigated whether Internet related stimuli can lead to distorted time perception. We found evidence that Internet and Facebook related stimuli can distort time perception due to attention and arousal related mechanisms. This highlights that Facebook related stimuli lead to an underestimation of time compared to Internet related stimuli, and both Facebook and Internet related stimuli were associated with better discriminability of time compared to matched neutral stimuli. Implications of these findings on addiction are discussed.
  • Bergström, Z., Williams, D., Bhula, M., & Sharma, D. (2016). Unintentional and intentional recognition rely on dissociable neurocognitive mechanisms. Journal of Cognitive Neuroscience, 28, 1838-1848. doi:10.1162/jocn_a_01010
    Distractibility can lead to accidents and academic failures, as well as memory problems. Recent evidence suggests that intentional recognition memory can be biased by unintentional recognition of distracting stimuli in the same environment. It is unknown whether unintentional and intentional recognition depend on the same underlying neurocognitive mechanisms. We assessed whether human participants’ recognition of previously seen (old) or not seen (new) target stimuli was affected by whether a to-be-ignored distractor was old or new. ERPs were recorded to investigate the neural correlates of this bias. The results showed that the old/new status of salient distractors had a biasing effect on target recognition accuracy. Both intentional and unintentional recognition elicited early ERP effects that are thought to reflect relatively automatic memory processes. However, only intentional recognition elicited the later ERP marker of conscious recollection, consistent with previous suggestions that recollection is under voluntary control. In contrast, unintentional recognition was associated with an enhanced late posterior negativity, which may reflect monitoring or evaluation of memory signals. The findings suggest that unintentional and intentional recognition involve dissociable memory processes.
  • Sharma, D. (2016). Priming can affect naming colours using the study-test procedure. Revealing the role of task conflict. Acta Psychologica, 189, 19-25. doi:10.1016/j.actpsy.2016.11.004
    The Stroop paradigm has been widely used to study attention whilst its use to explore implicit memory have been mixed. Using the non-colour word Stroop task we tested contrasting predictions from the Proactive-Control/Task-Conflict model (Kalanthroff, Avnit, Henik, Davelaar & Usher, 2015) that implicate response conflict and task conflict for the priming effects. Using the study-test procedure 60 native English speakers were tested to determine whether priming effects from words that had previously been studied would cause interference when presented in a colour naming task. The results replicate a finding by MacLeod (1996) who showed no differences between the response latencies to studied and unstudied words. However, this pattern was predominately in the first half of the study where it was also found that both studied and unstudied words in a mixed block were slower to respond to than a block of pure unstudied words. The second half of the study showed stronger priming interference effects as well as a sequential modulation effect in which studied words slowed down the responses of studied words on the next trial. We discuss the role of proactive and reactive control processes and conclude that task conflict best explains the pattern of priming effects reported.
  • Sharma, D. (2016). The variable nature of cognitive control in a university sample of young adult drinkers. Journal of Applied Social Psychology, 47, 118-123. doi:10.1111/jasp.12416
    The current study investigates the effect of task-irrelevant alcohol distractors on cognitive control and its interaction with heavy/light drinking in a group of young adult drinkers. It was hypothesised that alcohol distractors would result in a reduction of proactive control (reduced conflict adaptation) especially in heavy drinkers. 60 participants took part in a face-word version of the Stroop task preceded by an alcohol or neutral image. Light drinkers only showed a congruency effect which indicated a greater level of proactive control. Heavy drinkers showed a greater level of reactive control in which the conflict adaptation effect occurred with neutral images but not with alcohol images. Possible explanations are discussed.
  • Booth, R., Mackintosh, B., & Sharma, D. (2016). Working Memory Regulates Trait Anxiety-Related Threat Processing Biases. Emotion, 17, 616-627. doi:10.1037/emo0000264
    High trait anxious individuals tend to show biased processing of threat. Correlational evidence suggests that executive control could be used to regulate such threat-processing. On this basis, we hypothesised that trait anxiety-related cognitive biases regarding threat should be exaggerated when executive control is experimentally impaired by loading working memory. In Study 1, 68 undergraduates read ambiguous vignettes under high and low working memory load; later, their interpretations of these vignettes were assessed via a recognition test. Trait anxiety predicted biased interpretation of social threat vignettes under high working memory load, but not under low working memory load. In Study 2, 53 undergraduates completed a dot probe task with fear-conditioned Japanese characters serving as threat stimuli. Trait anxiety predicted attentional bias to the threat stimuli but, again, this only occurred under high working memory load. Interestingly however, actual eye movements toward the threat stimuli were only associated with state anxiety and this was not moderated by working memory load, suggesting that executive control regulates biased threat-processing downstream of initial input processes such as orienting. These results suggest that cognitive loads can exacerbate trait anxiety-related cognitive biases, and therefore represent a useful tool for assessing cognitive biases in future research. More importantly, since biased threat-processing has been implicated in the aetiology and maintenance of anxiety, poor executive control may be a risk factor for anxiety disorders.
  • Booth, R., Sharma, D., & Leader, T. (2015). The age of anxiety? It depends where you look: changes in STAI trait anxiety, 1970–2010. Social Psychiatry and Psychiatric Epidemiology, 51, 193-202. doi:10.1007/s00127-015-1096-0
    Purpose

    Population-level surveys suggest that anxiety has been increasing in several nations, including the USA and UK. We sought to verify the apparent anxiety increases by looking for systematic changes in mean anxiety questionnaire scores from research publications.


    Methods

    We analyzed all available mean State–Trait Anxiety Inventory scores published between 1970 and 2010. We collected 1703 samples, representing more than 205,000 participants from 57 nations.


    Results

    Results showed a significant anxiety increase worldwide, but the pattern was less clear in many individual nations. Our analyses suggest that any increase in anxiety in the USA and Canada may be limited to students, anxiety has decreased in the UK, and has remained stable in Australia.


    Conclusions

    Although anxiety may have increased worldwide, it might not be increasing as dramatically as previously thought, except in specific populations, such as North American students. Our results seem to contradict survey results from the USA and UK in particular. We do not claim that our results are more reliable than those of large population surveys. However, we do suggest that mental health surveys and other governmental sources of disorder prevalence data may be partially biased by changing attitudes toward mental health: if respondents are more aware and less ashamed of their anxiety, they are more likely to report it to survey takers. Analyses such as ours provide a useful means of double-checking apparent trends in large population surveys.
  • Albery, I., Sharma, D., Noyce, S., Frings, D., & Moss, A. (2015). Testing a frequency of exposure hypothesis in attentional bias for alcohol-related stimuli amongst social drinkers. Addictive Behaviors Reports, 1, 68-72. doi:10.1016/j.abrep.2015.05.001
    Aims
    To examine whether a group of social drinkers showed longer response latencies to alcohol-related stimuli than neutral stimuli and to test whether exposure to 1) an alcohol-related environment and 2) consumption related cues influenced the interference from alcohol-related stimuli.

    Methods
    A 2 × 2 × 2 × 5 factorial design with Exposure Group (high, low) and Consumption Group (high, low) as between-participant factors and Word Type (alcohol, neutral) and Block (1–5) as within-participant factors was used. Forty-three undergraduate university students, 21 assigned to a high exposure group and 22 to a low exposure group, took part in the experiment. Exposure Group was defined according to whether or not participants currently worked in a bar or pub. Consumption Group was defined according to a median split on a quantity–frequency measure derived from two questions of the Alcohol Use Disorders Identification Test (AUDIT) questionnaire. A modified computerised Stroop colour naming test was used to measure response latencies.

    Results
    Exposure and consumption factors interacted to produce greater interference from alcohol-related stimuli. In particular, the low consumption group showed interference from alcohol-related stimuli only in the high exposure condition. Exposure did not affect the magnitude of interference in the high consumption group.

    Conclusions
    Attentional bias is dependent upon exposure to distinct types of alcohol-related cues.
  • Hotham, S., & Sharma, D. (2015). The relationship between top-down attentional control and changes in weight. Eating Behaviours, 18, 81-83. doi:10.1016/j.eatbeh.2015.03.014
    Aim: To investigate the relationship between top-down attentional control in the presence of food cues and weight change over a 3-month period. Method: A Stroop task adapted to include background images of high-fat food and neutral items was completed by participants (N= 60). Top-down attentional control was assessed by adaptation effects (Stroop effect is smaller when the previous trial is incongruent). To assess weight change, measurements were taken immediately after the Stroop task (T1) and again 3- months later (T2). Differences in weight between T1 and T2 were calculated and three groups formed: weight gain (n=20); weight loss (n =20); no change in weight (n=20). Results: Differences in top-down attentional control were observed according to weight change. Participants who demonstrated reduced top-down attentional control also exhibited changes in weight (both loss and gain) over the 3-months. In contrast, the weight of participants who maintained top-down attentional control in the Stroop task remained stable. Conclusions: Findings suggest attentional control may have a role to play in actual eating behavior. Individuals who demonstrated reduced levels across of top-down attentional control
    also experienced changes in their weight over the 3-month period. Whether individuals lost or gained weight attentional control was reduced. This reduction was, however, not specific to high-fat food cues, but a general reduction in attentional control across both image conditions.
  • Weger, U., Loughnan, S., Sharma, D., & Gonidis, L. (2015). Virtually compliant: Immersive video gaming increases conformity to false computer judgments. Psychonomic Bulletin & Review, 22, 1111-1116. doi:10.3758/s13423-014-0778-z
    Real-life encounters with face-to-face contact are on the decline in a world in which many routine tasks are
    delegated to virtual characters—a development that bears both opportunities and risks. Interacting with such virtual-reality
    beings is particularly common during role-playing videogames, in which we incarnate into the virtual reality of
    an avatar. Video gaming is known to lead to the training and development of real-life skills and behaviors; hence, in the
    present study we sought to explore whether role-playing video gaming primes individuals’ identification with a computer
    enough to increase computer-related social conformity. Following immersive video gaming, individuals were indeed
    more likely to give up their own best judgment and to follow the vote of computers, especially when the stimulus context
    was ambiguous. Implications for human–computer interactions and for our understanding of the formation of identity
    and self-concept are discussed.
  • Clarke, S., Sharma, D., & Slater, D. (2015). Examining fast and slow effects for alcohol and negative emotion in problem and social drinkers. Addiction Research & Theory, 23, 24-33. doi:10.3109/16066359.2014.922961
    Attentional bias (AB) for alcohol-related stimuli has been consistently demonstrated in social and problem drinkers. The aims of this study were to: investigate whether AB for alcoholrelated stimuli could be described as a slow effect as well as a fast effect; how these effects relate to drinking behaviour; and the influence of the experimental procedure on priming effects. Two experiments were designed. In experiment 1, problem drinkers in treatment at a community alcohol service (N¼62) and a group of social drinking controls (N¼60) were assessed using the modified Stroop task with alcohol, negative emotion and neutral words.
    Drinking patterns were also recorded on the Khavari Alcohol Test. In experiment 2, social drinking controls (N¼40) completed the same procedure but were blinded to the study’s aims. In experiment 1, both groups demonstrated slower response times to alcohol-related than neutral stimuli in both fast and slow processes. Difference scores for alcohol compared to neutral words in the slow process were positively correlated with increases in drinking levels for both groups. In experiment 2, AB to alcohol-related stimuli disappeared when participants were unprimed. The findings highlight the importance of investigating the role of fast and slow processes in continued and problem drinking, alongside priming effects from the experimental procedure.
  • Wilkinson, D., Moreno, S., Ang, C., Deravi, F., Sharma, D., & Sakel, M. (2015). Emotional Correlates of Unirhinal Odor Identification. Laterality: Asymmetries of Body, Brain and Cognition, 21, 85-99. doi:10.1080/1357650X.2015.1075546
    It seems self-evident that smell profoundly shapes emotion, but less clear is the nature of this interaction. Here we sought to determine whether the ability to identify odors co-varies with self-reported feelings of empathy and emotional expression recognition, as predicted if the two capacities draw on common resource. Thirty six neurotypical volunteers were administered the Alberta Smell Test, The Interpersonal Reactivity Index and an emotional expression recognition task. Statistical analyses indicated that feelings of emotional empathy positively correlated with odor discrimination in right nostril, while the recognition of happy and fearful facial expressions positively correlated with odor discrimination in left nostril. These results uncover new links between olfactory discrimination and emotion which, given the ipsilateral configuration of the olfactory projections, point towards intra- rather than inter-hemispheric interaction. The results also provide novel support for the proposed lateralisation of emotional empathy and the recognition of facial expression, and give reason to further explore the diagnostic sensitivity of smell tests because reduced sensitivity to others’ emotions can mark the onset of certain neurological diseases.
  • Jones, A., Kramer, R., & Sharma, D. (2013). Sequential Effects in Judgements of Attractiveness: The Influences of Face Race and Sex. PloS ONE, 8, e82226. doi:doi:10.1371/journal.pone.0082226
    In perceptual decision-making, a person’s response on a given trial is influenced by their response on the immediately preceding trial. This sequential effect was initially demonstrated in psychophysical tasks, but has now been found in more complex, real-world judgements. The similarity of the current and previous stimuli determines the nature of the effect, with more similar items producing assimilation in judgements, while less similarity can cause a contrast effect. Previous research found assimilation in ratings of facial attractiveness, and here, we investigated whether this effect is influenced by the social categories of the faces presented. Over three experiments, participants rated the attractiveness of own- (White) and other-race (Chinese) faces of both sexes that appeared successively. Through blocking trials by race (Experiment 1), sex (Experiment 2), or both dimensions (Experiment 3), we could examine how sequential judgements were altered by the salience of different social categories in face sequences. For sequences that varied in sex alone, own-race faces showed significantly less opposite-sex assimilation (male and female faces perceived as dissimilar), while other-race faces showed equal assimilation for opposite- and same-sex sequences (male and female faces were not differentiated). For sequences that varied in race alone, categorisation by race resulted in no opposite-race assimilation for either sex of face (White and Chinese faces perceived as dissimilar). For sequences that varied in both race and sex, same-category assimilation was significantly greater than opposite-category. Our results suggest that the race of a face represents a superordinate category relative to sex. These findings demonstrate the importance of social categories when considering sequential judgements of faces, and also highlight a novel approach for investigating how multiple social dimensions interact during decision-making.
  • Kramer, R., Weger, U., & Sharma, D. (2013). The effect of mindfulness meditation on time perception. Consciousness and Cognition, 22, 846-852. doi:doi:10.1016/j.concog.2013.05.008
    Research has increasingly focussed on the benefits of meditation in everyday life and performance. Mindfulness in particular improves attention, working memory capacity, and reading comprehension. Given its emphasis on moment-to-moment awareness, we hypothesised that mindfulness meditation would alter time perception. Using a within-subjects design, participants carried out a temporal bisection task, where several probe durations are compared to “short” and “long” standards. Following this, participants either listened to an audiobook or a meditation that focussed on the movement of breath in the body. Finally, participants completed the temporal bisection task for a second time. The control group showed no change after the listening task. However, meditation led to a relative overestimation of durations. Within an internal clock framework, a change in attentional resources can produce longer perceived durations. This meditative effect has wider implications for the use of mindfulness as an everyday practice and a basis for clinical treatment.
  • Hotham, S., Sharma, D., & Hamilton-West, K. (2012). Restrained eaters preserve top-down attentional control in the presence of food. Appetite, 58, 1160-1163. doi:10.1016/j.appet.2012.03.011
    This study investigated the attentional control of restrained eaters when exposed to food. Restrained (N = 55) and unrestrained eaters (N = 56) completed a color word Stroop task. Top–down attentional control was assessed by adaptation effects (the Stroop effect is smaller when the previous trial is an incongruent color word than a congruent color word). Adaptation effects differed between restrained and unrestrained eaters according to the type of background image presented (high-fat food vs. non-food). Specifically, in restrained eaters adaptation effects did not differ as a function of image. In contrast, adaptation effects in unrestrained eaters were not observed with high-fat food. Motivation to either approach or avoid food may explain these differences.
  • Moss, A., Albery, I., & Sharma, D. (2011). Development of a repeated measures affective change blindness task. Behavior Research Methods, 43, 826-833. doi:10.3758/s13428-011-0072-1
  • Sharma, D., Booth, R., Brown, R., & Huguet, P. (2010). Exploring the temporal dynamics of social facilitation in the Stroop task. Psychonomic Bulletin & Review, 17, 52-58. doi:10.3758/PBR.17.1.52
    The importance of social context in affecting attention has recently been highlighted by the finding that the presence of a passive, nonevaluative confederate can improve selective attention. The underlying mechanism, however, remains unclear. In this paper, we argue that social facilitation can be caused by distractor inhibition. Two distinct sources of evidence are provided from an experiment employing the Stroop task with and without social presence. First, analysis of the response time (RT) distribution indicates that interference is reduced at relatively long RTs. This is consistent with an inhibitory mechanism, whose effects build up slowly. Further support is provided by showing that social facilitation is prevented by using short response-to-stimulus intervals that are thought to reduce cognitive control processes.

Book section

  • Booth, R., & Sharma, D. (2014). Working memory load elicits attentional bias to threat. In K. Kaniasty, K. Moore, S. Howard, & P. Buchwald (Eds.), Stress and anxiety: Applications to social and environmental threats, psychological well-being, occupational challenges, and developmental psychology (pp. 149-157). Logos Verlag.
    Anxious individuals tend to show attentional bias to threats and dangers; this is usually in-terpreted as a specific bias in threat-processing. However, they also tend to show general working memory and cognitive control impairments. We hypothesised that the lack of work-ing memory resources might contribute to attentional bias, by limiting anxious individuals’ ability to regulate their responses to emotional stimuli. If this is true, then loading working memory should elicit attentional bias to threat, even in non-anxious participants. We tested this hypothesis in two experiments, with participants unselected for anxiety. In Experiment 1, a phonological working memory load (remembering a string of digits) elicited an attentional bias to fear-conditioned Japanese words. In Experiment 2, a visuo-spatial working memory load (remembering a series of locations in a matrix of squares) elicited an attentional bias to emotional schematic faces. Results suggest that working memory and cognitive control may moderate the attentional bias to threat commonly observed in anxiety.

Conference or workshop item

  • Ates, F., Sharma, D., & Bergström, Z. (2016). Spontaneous recognition: Underlying neural mechanisms and the role of confidence. In International Conference on Memory. Budapest, Hungry. Retrieved from http://www.icom2016.com/
    Intentional recognition judgements to a target stimulus can be biased by spontaneous, unintentional recognition of familiar but task-irrelevant distractors. We investigated the underlying neural processes of such biases using EEG, focusing on how behavioural and EEG markers of bias correlate with participants’ confidence in their recognition judgements. Preliminary results suggest that spontaneous recognition of distractors elicited an early frontal-central positivity that has been linked with a relatively automatic familiarity process, whilst intentional target recognition also produced a later left-parietal positivity that reflects recollection. This latter ERP effect was particularly modulated by recognition confidence. The findings suggest dissociable neurocognitive processes contribute to unintentional and intentional recognition.
  • Gonidis, L., Sharma, D., & Brooks, J. (2016). The Effects of Memory Load on Time Perception of Facebook and Internet Related Stimuli. In International Conference on Memory. Budapest, Hungry. Retrieved from http://www.icom2016.com/
    Previous research has shown that salient stimuli can impact our time perception either by affecting our arousal or attention. Furthermore, concurrent
    nontemporal tasks can cause interference in our perception of time. In this study, participants performed a time bisection task with Facebook,
    Internet, or Neutral stimuli in conjunction with a 1-Back or a 2-Back task. Findings suggest that the memory task and the salient stimuli had
    independent effects on time perception. The 2-Back task (compared to 1-Back task) produced an overestimation of time and worst discriminability
    whereas the salient (facebook and internet related) stimuli (compared to neutral stimuli) produced an overestimation but better discriminability of
    time.
  • Warhel, M., Pappous, A., & Sharma, D. (2016). The effect of mindfulness meditation in reducing pain and improving the mental health of injured athletes. In 21st annual congress of the European College of Sport Science. Crossing Borders through Sport Science. Vienna, Austria. Retrieved from http://ecss-congress.eu/2016/16/
  • cox, z, & Sharma, D. (2016). The Effect of Longitudinal Short-Meditation Interventions on the Cognitive Alerting Network. In Second International Conference on Mindfulness (ICM-2). Rome, Italy. Retrieved from http://www.cmc-ia.org/icm2016rome/conference-program/
    Introduction
    Research shows that an improved ability to maintain an alert state, that is a readiness to engage in attentional processing, arises in long-term meditators. This paper extends this finding, demonstrating improved vigilance in novices using short meditation interventions.

    Method
    We used a longitudinal design (1 pre-test session, 8 sessions x 8 minutes over 4 weeks) which was completed by 57 undergraduate novices. Each session, other than the pre-test session, contained an intervention (body scan meditation vs. mindful colouring vs. video watching) followed by an Attention Network Test (ANT), as well as mood and mindfulness state questionnaires.

    Results
    A significant interaction was found between groups in their ANT Alerting scores from pre-test to post 8th intervention (F (2, 54) = 3.17, p = .050). The meditative groups’ alerting scores remained fairly stable but both the control groups’ scores increased on the final test meaning that they took longer to respond. There was also a significant interaction between Mindful Attention Awareness Scale scores pre- and post- individual interventions (F (2, 52) = 3.21, p = .049) with the meditation and colouring groups increasing their mindfulness scores compared to a reduction in the video group score.

    Discussion
    Results suggest that even short mindfulness interventions can positively impact individuals’ abilities to maintain higher levels of attentional alertness and vigilance in certain tasks. However, the duration of these effects remains unclear.
  • Ates, F., & Sharma, D. (2015). Effects of Working memory on spontaneous recognition. In 32nd annual BPS cognitive psychology section conference. University of Kent.
  • Sharma, D. (2015). Regulation of the conflict adaptation effect by emotion. In European Society for Cognitive Psychology. Cyprus. Retrieved from http://www.escop2015.org/files/ESCOP2015_Detailed_Programme_15092015.pdf
    A number of recent studies have shown that emotion can moderate the control of cognitive conflict on Stroop tasks. Much of this work suggests that positive mood, compared to negative or neutral mood, reduce cognitive control. This has been demonstrated by a reduction in the conflict adaptation effect with positive mood induction. Recently Padmala, Bauer and Pessoa (2011) embedded irrelevant negative and neutral images in between trials on a face-word version of the Stroop task. They reported that negative images, compared to neutral images, can also reduce cognitive control. In our research we report on two studies. First, a direct replication of Padmala et al’s study that demonstrates further support for their finding that negative images reduce cognitive control. In a second study we show that the conflict adaptation effects are similar for irrelevant positive and neutral images.
  • Booth, R., Mackintosh, B., & Sharma, D. (2015). Working memory regulates anxiety-related threat processing biases. In International Society for Research on Emotions (ISRE). University of Geneva, Switzerland.
    Anxious individuals tend to show biased processing of threat (e.g. Mathews & MacLeod, 2005). Executive control could be used to regulate such threat-processing (Schmeichel, Volokhov, & Demaree, 2008), and theorists have suggested that impaired executive control may be a risk factor for anxiety (Mathews & MacLeod, 2005; Ouimet, Gawronski, & Dozois, 2009). On these bases, we hypothesised that anxiety-related cognitive biases regarding threat should be more apparent when executive control is experimentally impaired by loading working memory. In Study 1, 68 undergraduates read ambiguous vignettes under high and low working memory load; later, their interpretations of these vignettes were assessed via a recognition test. Trait anxiety predicted biased interpretation of social threat vignettes under high working memory load, but not under low working memory load. In Study 2, 53 undergraduates completed a dot probe task with fear-conditioned Japanese characters serving as threat stimuli. Trait anxiety predicted attentional bias to the threat stimuli but, again, this only occurred under high working memory load. Interestingly however, actual eye movements toward the threat stimuli were associated with state rather than trait anxiety and this relationship was not moderated by working memory load, suggesting that executive control regulates biased threat-processing downstream of initial input processes such as orienting. These results suggest that cognitive loads might be a useful tool for assessing cognitive biases in future research. More importantly, since biased threat-pro cessing has been implicated in the aetiology and maintenance of anxiety, poor executive control may indeed be a risk factor for anxiety disorders.
  • Gonidis, L., & Sharma, D. (2015). Internet addiction and time perception. In Emerging methods in addiction research programme. South Bank University.
    Research has shown that non-substance addictions can cause similar attention biases as substance addictions. The last decades, together with the boom of the internet a new non-substance addiction materialized, the Internet or Online addiction (IA). The last years more research has explored the underlying mechanisms that are involved in IA, however there is not much research on how IA affects our time perception. With the current study, using a time bisection task, we aimed to explore possible attention bias towards internet related stimuli and also look for possible practice effects from performing the task five consecutive times (five blocks). Analysis of the Weber Ratios (WR) suggests that Internet related stimuli maintain a good discriminability across blocks, contrary to neutral stimuli that lead to decreasing discriminability. Furthermore, analysis of the bisection points (BP) suggests that participants’ arousal levels drop at a much slower pace across blocks for Internet related stimuli compared to neutral matched stimuli.
  • Hotham, S., & Sharma, D. (2015). How availability of food affects attentional control in restrained eaters: Eye movements in a pictorial-adapted antisaccade task. In Emerging methods in addiction research programme. South Bank University.
    Background: Previous research notes diminished attentional control in restrained eaters when presented with food images. This loss of attentional control is attributed to both approach and avoidance biases. Two eye-tracking experiments extended these findings by exploring how the availability of food affects both types of attentional control.

    Methods: In experiment one participants (N = 72) completed a pictorial-adapted antisaccade task (food vs. neutral). In experiment two, prior to completing the antisaccade task, participants (N = 70) chose six unhealthy snacks to consume after the experiment (i.e., actionable food). DEBQ assessed levels of eating restraint. Using saccade latency, a bias score was calculated as a proxy for attentional control (Saccade Latency Food – Saccade Latency Neutral).

    Findings: In the first experiment, attentional control between restrained and unrestrained eaters did not differ significantly. However in the second experiment, when participants were expecting to eat, restrained eaters demonstrated an approach bias towards food images.

    Discussion: Restrained eaters are typically unsuccessful at losing weight, despite a strong intention to diet. Loss of attentional control in the presence of food images may contribute to this relationship. Expecting to eat unhealthy food reinforces this vulnerability in restrained eaters and offers a potential explanation for why weight loss is not achieved.
  • Sharma, D. (2015). The role of alcohol cues in the modulation of top-down cognitive control in a group of Problem drinkers. In Emerging methods in addiction research programme. South Bank University.
    Previous research has shown that top-down cognitive control is increased in the presence of conflicting stimuli (sequential modulation effect, SME). One explanation for the SME implicates the Anterior Cingulate Cortex in top-down cognitive control (Botvinick, Braver, Barch, Carter & Cohen, 2001). The SME has also been shown to be modulated by negative emotional cues (Padmala, Bauer & Pessoa, 2011 et al). Here we report on a study to see whether alcohol cues can modulate the SME using a face-word Stroop task in a group of social drinkers (problem and non-problem drinkers). Our results demonstrate that in a group of problem drinkers alcohol cues reduce the SME indicating a reduction in top-down cognitive control.
  • Hotham, S., & Sharma, D. (2014). How availability of food affects attentional control in restrained eaters: Eye movements in a pictorial-adapted antisaccade task. In Division of Health Psychology Annual Conference (DHP). Park Inn Hotel, York. Retrieved from https://www.bps.org.uk/system/files/user-files/Division%20of%20Health%20Psychology%20Annual%20Conference%202014/provisional_scientific_programme_timetable_2014_v13.pdf#page=5
    Background: Previous research notes diminished attentional control in restrained eaters when presented with food images. This loss of attentional control is attributed to both approach and avoidance biases. Two eye-tracking experiments extended these findings by exploring how the availability of food affects both types of attentional control.
    Methods: In experiment one participants (N = 72) completed a pictorial-adapted antisaccade task (food vs. neutral). In experiment two, prior to completing the antisaccade task, participants (N = 70) chose six unhealthy snacks to consume after the experiment (i.e., actionable food). DEBQ assessed levels of eating restraint. Using saccade latency, a bias score was calculated as a proxy for attentional control (Saccade Latency Food – Saccade Latency Neutral). A 2 (prosaccade bias vs. antisaccade bias) x 2 (restrained vs. unrestrained) mixed-model ANOVA was used.
    Findings: In the first experiment, attentional control between restrained and unrestrained eaters did not differ significantly (F = .03, p = .86). However in the second experiment, when participants were expecting to eat, restrained eaters demonstrated an approach bias towards food images (F = 4.85, p <.05). In contrast, attentional control in unrestrained eaters was not affected by image type (F = .28, p = .60).
    Discussion: Restrained eaters are typically unsuccessful at losing weight, despite a strong intention to diet. Loss of attentional control in the presence of food images may contribute to this relationship. Expecting to eat unhealthy food reinforces this vulnerability in restrained eaters and offers a potential explanation for why weight loss is not achieved.
  • Hotham, S., & Sharma, D. (2014). How availability of food affects attentional control in restrained eaters: Eye movements in a pictorial-adapted antisaccade task. In Experimental Psychological Society. University of Kent. Retrieved from http://www.eps.ac.uk/images/epsfiles/kent%20programme%20apr%20-%202014%20-final.pdf#page=8
    How the availability of food affects top-down attentional control in restrained eaters: Eye movements in a pictorial-adapted antisaccade task.
    Aim: Two eye tracking experiments utilised a pictorial-adapted antisaccade task to investigate the relationship between top-down attentional control in the presence of food images and eating restraint. In addition, the availability of food in the two experiments was manipulated to examine how the expectation of eating high-fat food may also affect top-down attentional control.
    Method: In the first experiment participants (N = 72) completed a pictorial-adapted antisaccade task (high-fat food vs. neutral images) to assess top-down attentional control. In the second participants (N = 70), prior to completing the antisaccade task, were asked to choose six unhealthy snacks to consume once the experiment was completed (i.e., actionable food). Participants completed the DEBQ to assess levels of eating restraint.
    Results: In the first experiment, levels of eating restraint and top-down attention in the food image condition were not related. However in the second experiment, when participants were expecting to eat, restrained eaters were slower to move their attention away from the food image compared to unrestrained eaters.
    Conclusions: When actionable food is not present, top-down attention in restrained eaters is unaffected by food cues. However when actionable food cues are present, top-down attentional control in restrained eaters is diminished.
  • Kramer, R., Weger, U., & Sharma, D. (2013). The Effect of Mindfulness Meditation on Time Perception. In 53th meeting of the Psychonomic Society. Toronto, Canada.
  • Kramer, R., Weger, U., & Sharma, D. (2013). The Effect of Mindfulness Meditation on Time Perception. In EPS. Bangor University.
  • Booth, R., Sharma, D., & Leader, T. (2012). Is trait anxiety increasing? STAI scores across 40 years and 40 nations. In STAR conference. Palma de Mallorca.
  • Hotham, S., Sharma, D., & Hamilton-West, K. (2012). Restrained eaters preserve top-down attentional control in the presence of food. In Consortium of European Research on Emotion (CERE). University of Kent.
  • Dumay, N., Sharma, D., Kellen, N., & Abdelrahim, S. (2012). Setting the alarm: the role of consolidation in acquiring the emotional attributes of words. In BAPS-SEPEX Joint conference between BAPS (Belgian Association for Psychological Sciences) and SEPEX (Sociedad Española de Psicología Experimental).. University of Liège, Belgium.
  • Dumay, N., Sharma, D., Kellen, N., & Abdelrahim, S. (2012). Setting the alarm: the role of consolidation in acquiring the emotional attributes of words. In Abstracts of the Meeting of the Experimental Psychology Society (p. 42). University College London, UK.
  • Dumay, N., Sharma, D., Kellen, N., & Abdelrahim, S. (2011). Setting the alarm takes longer than you think: the role of consolidation in acquiring words’ emotional attributes. In 17th Conference of the European Society for Cognitive Psychology (ESCoP) (pp. 157-157). San Sebastian, Spain.
  • Booth, R., Sharma, D., & Leader, T. (2011). Is trait anxiety increasing? STAI scores across 40 years and 40 nations. In BPS annual conference. Glasgow.
  • Hotham, S., & Sharma, D. (2010). The role of cognitive control in restrained eating. In BPS Health Psychology Workshop. Middlesex University, Uk.

Thesis

  • Ates, F. (2018). The Role of Working Memory in Spontaneous Recognition: Neural Correlates and Behavioural Influences in the Memory Stroop Paradigm.
    Research suggests that unintentional recognition of distracting non-target stimuli can bias goal-related, intentional recognition judgements to target stimuli encountered in the same environment. Spontaneous recognition (SR) effect can be defined as the unintentional recognition of stimuli and is measured by the effect of familiarity to distractors on a recognition task. This thesis investigated how previously seen or not-seen distractors affect recognition of targets when working memory (WM) resources are manipulated by a secondary WM load task (chapter 2), using both behavioural and ERP measures (Chapter 3). The findings suggest that when working memory resources are low, SR is then easier to observe. Additionally, neural and memory processes are dissociable for unintentional and intentional recognition and retrieval monitoring is found to be enhanced when the new targets were paired with old distractors. Furthermore, the findings on the early ERPs may suggest that the proactive control might be activated. Finally, a set of experiments revealed that, SR effect may not be related to conscious awareness since having a low or high confidence did not modulate the SR effect indicating a lack of conscious awareness of the SR effect (Chapter 4). Together these findings may help to understand the mechanisms underlying the SR effect.
  • Gonidis, L. (2015). Do Gambling Related Stimuli Lead to Intrusive Cognitions?.
    Studies have demonstrated that gambling stimuli can trigger attentional biases to pathological gamblers. However, with the continuous increase of exposure to gambling stimuli it is important to investigate the effect of gambling stimuli on the general population. The present research investigated whether gambling stimuli can lead to intrusive cognitions that could affect time perception, gambling decisions and could elicit craving to gamble. In study 1, using a gambling Stroop test as a prime, we showed that intrusive cognitions can affect gambling decisions and elicit desire to gamble. In study 2, using a time bisection task without any primes we did not find any such effects. In study 3, individuals had to perform the time bisection task twice with a priming task between attempts. Findings suggest that there were no intrusive cognitions as a result of a gambling related prime. There was however an overall effect of priming on time perception suggesting that mind-set could affect time perception. Future research paths are also suggested.

Forthcoming

  • Allen, J., Hellerstedt, R., Sharma, D., & Bergström, Z. (2019). Distraction by unintentional recognition: Neurocognitive mechanisms and effects of aging. Psychology and Aging. doi:10.1037/pag0000398
    Sometimes, we intentionally evaluate stimuli to assess if we recognise them, whereas other times, stimuli automatically elicit recognition despite our efforts to ignore them. If multiple stimuli are encountered in the same environment, intentional recognition judgements can be biased by unintentional recognition of to-be-ignored stimuli. Aging is associated with increased distractibility and impaired intentional retrieval processes, which can make older adults more susceptible to distraction-induced recognition biases. We measured recognition memory performance, ERPs and EEG oscillations in old (60-74) and young (18-24) adults to investigate how aging affects unintentional and intentional memory processes, and how these processes interact over time to produce distraction-induced recognition biases. Older participants had poorer intentional recognition memory, but the biasing effect of unintentional distractor recognition was similar across age groups. ERP effects related to intentional and unintentional recognition that were strongly expressed in the younger group were reduced or absent in the older group. Furthermore, the older group showed qualitatively different ERP activity during intentional recognition compared to the younger group. However, similar patterns of theta and alpha oscillations were found in both age groups, who showed theta power increases for both intentional and unintentional recognition, whereas alpha power was enhanced for intentional recognition but reduced for unintentional recognition. Overall, the findings show that unintentional and intentional recognition involve multiple dissociable memory processes that have different time-courses and functional characteristics, and are differentially affected by aging. Whereas aging has strong effects on the neurocognitive mechanisms underlying intentional recognition memory, unintentional recognition mechanisms are less affected.
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