119 Spatial Conflict is Encoded in Human MT+. Issue Volume 61:Issue CN Supp. 1(2014)Supplement (1st August 2014)

• Record Type: Journal Article
• Authors: Mikell, Charles B.; Smith, Elliot H.; Brown, Lauren Terese; McKhann, Guy M.; Sheth, Sameer A.
• Is Part Of: Neurosurgery. Volume 61:Issue CN Supp. 1(2014)Supplement
• Page Start: 198
• Page End: 198
• Publication Date: 2014-08-01
• Subjects: Nervous system -- Surgery -- Periodicals; 617.48005
• DOI: 10.1227/01.neu.0000452393.54414.ca
• Languages: English
• ISSNs: 0148-396X

Abstract

Abstract: INTRODUCTION: Normal behavior depends upon the ability to inhibit automatic responses in favor of more thoughtful, controlled responses. However, engaging these controlled responses requires detecting conditions of conflict where cognitive resources must be brought to bear. Details regarding this conflict-detecting machinery are unclear in humans. METHODS: Two patients with intractable epilepsy and implanted grid electrodes over the temporooccipital junction performed a Stroop-like behavioral task, the multi-source interference task. After low-pass filtering (<30 Hz), re-referencing, and censoring of noisy trials, ERPs were calculated for trial response over the temporooccipital junction. Cluster-based statistics were used to detect significant differences ( P < .01) between the low- and high-conflict conditions. Wavelet decomposition was also performed to evaluate the high gamma band (70-110 Hz), a sign of local neuronal activity. RESULTS: Strong high gamma responses to the cue were seen, consistent with local neuronal activity. Electrodes with ERPs differentiating easy and hard trials were found near the temporooccipital junction in both patients. For each electrode, differences between easy and hard trials became statistically significant 100 to 500 milliseconds prior to button press. CONCLUSION: These data suggest that conflict is encoded at an early stage of visual processing, likely in area MT+. Conflict is detected 100 to 500 milliseconds prior to motor output, reflecting the need to update motor plans in the setting of ongoing conflict.