CCNCS Seminar Details
Modulation of Emotion: A Computational and Real-time Functional MRI Approach
|Speaker:||Dr Li Su|
|Date/Time:||Wednesday 10 June 2009, 4.15pm|
|Location:||SB110B, Computing Laboratory, Cornwallis|
I will talk about both my PhD and post-doc work. In the beginning, I will focus on computational modelling of the Attentional Blink (AB) paradigm, which suggests that there is a 400-500ms window in which a second target (T2) is vulnerable to being missed following a first target (T1). A variant of this task (the key distractor AB task) focuses on emotional effects on temporal attention. This experiment replaces the T1 with a key distractor, the salience of which determines to what extent a following target is blinked. I present a model of the key distractor AB task based around the interaction of three subsystems: implicational, propositional and body state. The implicational subsystem extracts a generic form of meaning, while the propositional subsystem extracts referentially specific meaning and the body state subsystem reflects somatic responses. The model explains the key distractor AB task in terms of the movement of attentional focus amongst the subsystems. Emotional effects are modelled through the interaction of all three subsystems. In the second half of my talk, I will present work from my post-doc, which demonstrates the feasibility of self-regulating the right anterior insula (RAI) using real-time functional magnetic resonance imaging (rt-fMRI) on our 3T GE scanner. Such rt-fMRI provides a novel brain-computer interface that can be used for neural feedback. This nonpharmacological therapy has been shown to have clinical promise. Studies from healthy controls suggest RAI is amenable to regulation, a region that is implicated in affective processing, and hypoactive in some psychiatric conditions. Our data shows that using the Blood Oxygenated Level Dependant signal from the RAI as neural feedback, participants can learn to control RAI activation. Finally I would like to discuss the potential of using the model to guide the experimental design and data analysis in the imaging study, in particular, to use emotional AB task as a test and pre-test of the behavioural changes introduced by rt-fMR. Moreover, the model may be able to predict such changes.