Amygdala responses to fearful and happy facial expressions under conditions of binocular suppression.

@article{citeulike:1287693, abstract = {The human amygdala plays a crucial role in processing affective information conveyed by sensory stimuli. Facial expressions of fear and anger, which both signal potential threat to an observer, result in significant increases in amygdala activity, even when the faces are unattended or presented briefly and masked. It has been suggested that afferent signals from the retina travel to the amygdala via separate cortical and subcortical pathways, with the subcortical pathway underlying unconscious processing. Here we exploited the phenomenon of binocular rivalry to induce complete suppression of affective face stimuli presented to one eye. Twelve participants viewed brief, rivalrous visual displays in which a fearful, happy, or neutral face was presented to one eye while a house was presented simultaneously to the other. We used functional magnetic resonance imaging to study activation in the amygdala and extrastriate visual areas for consciously perceived versus suppressed face and house stimuli. Activation within the fusiform and parahippocampal gyri increased significantly for perceived versus suppressed faces and houses, respectively. Amygdala activation increased bilaterally in response to fearful versus neutral faces, regardless of whether the face was perceived consciously or suppressed because of binocular rivalry. Amygdala activity also increased significantly for happy versus neutral faces, but only when the face was suppressed. This activation pattern suggests that the amygdala has a limited capacity to differentiate between specific facial expressions when it must rely on information received via a subcortical route. We suggest that this limited capacity reflects a tradeoff between specificity and speed of processing.}, address = {Cognitive Neuroscience Laboratory, School of Behavioral Science, University of Melbourne, Parkville, Victoria 3010, Australia.}, author = {Williams, M. A. and Morris, A. P. and McGlone, F. and Abbott, D. F. and Mattingley, J. B. }, citeulike-article-id = {1287693}, doi = {10.1523/JNEUROSCI.4977-03.2004}, issn = {1529-2401}, journal = {J Neurosci}, keywords = {amygdala, emotion, expression, face, fmri, masked}, month = {March}, number = {12}, pages = {2898--2904}, posted-at = {2007-05-16 10:57:13}, priority = {5}, title = {Amygdala responses to fearful and happy facial expressions under conditions of binocular suppression.}, url = {http://dx.doi.org/10.1523/JNEUROSCI.4977-03.2004}, volume = {24}, year = {2004} }

TY - JOUR ID - citeulike:1287693 L3 - citeulike-article-id:1287693 TI - Amygdala responses to fearful and happy facial expressions under conditions of binocular suppression. JF - J Neurosci VL - 24 IS - 12 SP - 2898 EP - 2904 AD - Cognitive Neuroscience Laboratory, School of Behavioral Science, University of Melbourne, Parkville, Victoria 3010, Australia. SN - 1529-2401 N2 - The human amygdala plays a crucial role in processing affective information conveyed by sensory stimuli. Facial expressions of fear and anger, which both signal potential threat to an observer, result in significant increases in amygdala activity, even when the faces are unattended or presented briefly and masked. It has been suggested that afferent signals from the retina travel to the amygdala via separate cortical and subcortical pathways, with the subcortical pathway underlying unconscious processing. Here we exploited the phenomenon of binocular rivalry to induce complete suppression of affective face stimuli presented to one eye. Twelve participants viewed brief, rivalrous visual displays in which a fearful, happy, or neutral face was presented to one eye while a house was presented simultaneously to the other. We used functional magnetic resonance imaging to study activation in the amygdala and extrastriate visual areas for consciously perceived versus suppressed face and house stimuli. Activation within the fusiform and parahippocampal gyri increased significantly for perceived versus suppressed faces and houses, respectively. Amygdala activation increased bilaterally in response to fearful versus neutral faces, regardless of whether the face was perceived consciously or suppressed because of binocular rivalry. Amygdala activity also increased significantly for happy versus neutral faces, but only when the face was suppressed. This activation pattern suggests that the amygdala has a limited capacity to differentiate between specific facial expressions when it must rely on information received via a subcortical route. We suggest that this limited capacity reflects a tradeoff between specificity and speed of processing. KW - amygdala KW - emotion KW - expression KW - face KW - fmri KW - masked AU - Williams, MA AU - Morris, AP AU - McGlone, F AU - Abbott, DF AU - Mattingley, JB PY - 2004/03/24/ UR - http://dx.doi.org/10.1523/JNEUROSCI.4977-03.2004 ER -