PT  - JOURNAL ARTICLE
AU  - Stephan Moratti
AU  - Cristina Saugar
AU  - Bryan A. Strange
TI  - Prefrontal-Occipitoparietal Coupling Underlies Late Latency Human Neuronal Responses to Emotion
AID  - 10.1523/JNEUROSCI.2917-11.2011
DP  - 2011 Nov 23
TA  - The Journal of Neuroscience
PG  - 17278--17286
VI  - 31
IP  - 47
4099  - http://www.jneurosci.org/content/31/47/17278.short
4100  - http://www.jneurosci.org/content/31/47/17278.full
SO  - J. Neurosci.2011 Nov 23; 31
AB  - Enhanced late positive potentials (LPPs) evoked by highly arousing unpleasant and pleasant stimuli have been consistently observed in event-related potential experiments in humans. Although the psychological factors modulating the LPP have been studied in detail, the neurobiological underpinnings of this response remain poorly understood. Current models suggest that the LPP is a product of both an automatic facilitation of perceptual activity, as well as postperceptual processing under cognitive control. Here we applied magnetoencephalography (MEG) and beamformer analysis combined with Granger causality measures to provide a mechanistic account for LPP generation that reconciles these two models. We demonstrate that the magnetic homolog of the LPP, mLPP, is localized within bilateral occipitoparietal and right prefrontal cortex. Critically, directed functional connectivity analysis between these brain regions, indexed by Granger causality, demonstrates stronger bidirectional influences between frontal and occipitoparietal cortex for high arousing emotional relative to low arousing neutral pictures. Thus, both bottom-up and top-down accounts of the late latency response to emotion derived from psychological studies can be explained by a reciprocal codependency between activity in prefrontal and occipitoparietal cortex.