Neural Correlates and Functional Connectivity of Emotional Face Perception in Clinical and Non-clinical Depression

Proposal details

Title: Neural Correlates and Functional Connectivity of Emotional Face Perception in Clinical and Non-clinical Depression
Research Area(s): Emotion and Self Regulation
Background: Perception of biologically salient signals of emotion such as facial expressions of others is essential to effective maintenance of human relationships. Evidence now suggests that negative stimuli are processed more rapidly and produce greater responses than neutral or positive stimuli (Carretié et al., 2001; Northoff et al., 2000; Williams et al., under review). Evidence from behavioural studies employing the emotional stroop paradigm for example, further suggest that depressed individuals display a stronger negativity bias than non-depressed individuals (eg. Segal, 1995; Williams et al., 1996). However, other studies have also suggested that depressed patients display a more general visual perceptive deficit (Asthana et al., 1998).
Aims: The aim of this study therefore is to examine the temporal and spatial correlates of as well as the functional connectivity in depression. Our initial research will focus on non-clinically depressed patients which may help minimise confounds that need to be dealt with in clinically depressed samples such as disease hetereogeneity and medication history. It is hypothesised that depressed participants will display more rapid (as indicated by event-related potential or ERP responses) and larger (as indicated by ERP and functional magnetic resonance imaging) responses as well as increased functional connectivity (as indicated by gamma synchrony and BOLD functional connectivity analysis) to negative facial expressions (relative to positive facial expressions) if indeed depressed individuals display increased negativity bias compared to age and sex matched controls. If however, depressed individuals display a more general visual perceptive deficit, then we would hypothesise slower and smaller responses as well as reduced functional connectivity to both negative and positive emotional facial expressions.
Method: Group (Depressed, Non-Depressed) X Condition (Positive, Negative facial expressioned) ANOVAs will be employed for ERP and fMRI data to determine whether non-clinically depressed participants display a negativity bias or a more general perceptive bias.