Impaired fronto-temporal processing of emotion in schizophrenia.
OBJECTIVE
Abnormal emotion processing in schizophrenia affects social and functional outcome. Spatiotemporal brain mechanisms underlying this deficit are unclear.


METHODS
Event-related potential (ERP) responses to emotional and neutral face processing during an implicit (gender detection) and an explicit (expression detection) task were compared between a group of healthy volunteers (n=10) and a group of patients with schizophrenia (n=10).


RESULTS
Whereas patients had normal primary visual cortex responses, the early modulation of occipital, temporal, and frontal responses by emotional expression observed in controls was absent in patients. The occipito-temporal N170 amplitude was reduced in patients relative to controls during expression detection, but not during gender detection. Frontal activity within 180-250ms was reduced in patients compared to controls. As opposed to controls, no significant difference was seen in patients at the right temporal electrode (T6) between amplitudes of long-latency ERPs elicited by distinct emotions during the expression detection task.


CONCLUSIONS
In patients with schizophrenia, abnormal early extraction of expression-related information in the occipito-temporal cortex (before 170ms) impairs structural encoding of facial expressions (N170) and may disrupt motivation- and task-dependent context processing (180-250ms time window) of expression-related facial features. Moreover, top-down neuromodulation from frontal and limbic structures to visual occipito-temporal cortex may not be sufficient to optimize the extraction of expression-specific face features.
Bediou
B
B
Service du Professeur Dalery, centre hospitalier Le Vinatier, université Lyon-1, EA 3092, 95, boulevard Pinel, 69677 Bron cedex, France. benoit.bediou@ch-le-vinatier.fr <benoit.bediou@ch-le-vinatier.fr>
Hénaff
M-A
MA
Bertrand
O
O
Brunelin
J
J
d'Amato
T
T
Saoud
M
M
Krolak-Salmon
P
P
D000328:Adult; D004644:Emotions / Q000502:physiology*; D005145:Face; D005260:Female; D005625:Frontal Lobe / Q000503:physiopathology*; D006801:Humans; D008297:Male; D009778:Occipital Lobe / Q000503:physiopathology; D011597:Psychomotor Performance / Q000502:physiology; D021641:Recognition, Psychology / Q000502:physiology; D012559:Schizophrenia / Q000503:physiopathology*; D012565:Schizophrenic Psychology; D012727:Sex Characteristics; D012938:Social Perception; D013702:Temporal Lobe / Q000503:physiopathology*; D016896:Treatment Outcome; D014793:Visual Cortex / Q000502:physiology