Allocation of attention to the eye and mouth region of faces in schizophrenia patients

The role of attention processes in facial affect recognition in schizophrenia

INTRODUCTION

Studies investigating the involvement of attention processes in facial affect recognition (FAR) have been contradictory, with some suggesting a generalised cognitive deficit, whereas others a specialised deficit in affect recognition. Given the ubiquity of both attention and emotion perception deficits in schizophrenia, we examined whether specific attentional processes, in fact, mediate FAR.

METHODS

Patients with schizophrenia (n = 38) and healthy controls (n = 24) performed tests assessing FAR and attention processes, specifically, visual attention (Trail Making Test A), sustained attention/inhibition (Rapid Visual Processing subtest; Cambridge Automated Neuropsychological Test Battery), and attention to details in facial features (AFF). AFF and FAR were assessed with newly devised experimental procedures.

RESULTS

Hierarchical multiple regression analyses showed a similar pattern of association between attention processes and FAR in both participant groups with respect to all attention processes investigated, predicting FAR accuracy. Additionally, visual attention predicted accuracy in happiness, disgust and surprise, whereas AFF predicted accuracy in anger and fear. Regarding FAR processing speed, no attention process predicted participants' performance on correct responses; AFF response speed predicted participants' FAR response speed, but only on incorrect responses.

DISCUSSION

The present findings highlight the role of attentional processes in emotion recognition, as deficits in the former were predictive of impairments in the latter. Furthermore, AFF appears to be involved in the discrimination of negatively valenced facial expressions. The lack of association between attentional processes and FAR processing speed, particularly regarding correct responses, might reflect the differential pattern of activation of cortical and subcortical structures involved in these cognitive processes.

The effect of neurogranin on neural correlates of episodic memory encoding and retrieval

Neurogranin (NRGN) is the main postsynaptic protein regulating the availability of calmodulin-Ca(2+) in neurons. NRGN is expressed exclusively in the brain, particularly in dendritic spines and has been implicated in spatial learning and hippocampal plasticity. Genetic variation in rs12807809 in the NRGN gene has recently been confirmed to be associated with schizophrenia in a meta-analysis of genome-wide association studies: the T-allele was found to be genome-wide significantly associated with schizophrenia. Cognitive tests and personality questionnaires were administered in a large sample of healthy subjects. Brain activation was measured with functional magnetic resonance imaging (fMRI) during an episodic memory encoding and retrieval task in a subsample. All subjects were genotyped for NRGN rs12807809. There was no effect of genotype on personality or cognitive measures in the large sample. Homozygote carriers of the T-allele showed better performance in the retrieval task during fMRI. After controlling for memory performance, differential brain activation was evident in the anterior cingulate cortex for the encoding and posterior cingulate regions during retrieval. We could demonstrate that rs12807809 of NRGN is associated with differential neural functioning in the anterior and posterior cingulate. These areas are involved in episodic memory processes and have been implicated in the pathophysiology of schizophrenia in structural and functional imaging as well as postmortem studies.