2015年6月29日月曜日

Orbitofrontal lesions eliminate signalling of biological significance in cue-responsive ventral striatal neurons

Nisha K. Cooch, Thomas A. Stalnaker, Heather M. Wied, Sheena Bali-Chaudhary, Michael A. McDannald, Tzu-Lan Liu & Geoffrey Schoenbaum
Nature Communications 6, Article number: 7195

ラットの腹側線条体(ventral striatum)は「報酬を示す手掛かり刺激」に対してその報酬量に比例して反応することが知られているが、眼窩前頭前野(orbitofrontal cortex, OFC)を破壊すると、手掛かり刺激そのものには反応するがその報酬量への反応は消える。

The ventral striatum has long been proposed as an integrator of biologically significant associative information to drive actions. Although inputs from the amygdala and hippocampus have been much studied, the role of prominent inputs from orbitofrontal cortex (OFC) are less well understood. Here, we recorded single-unit activity from ventral striatum core in rats with sham or ipsilateral neurotoxic lesions of lateral OFC, as they performed an odour-guided spatial choice task. Consistent with prior reports, we found that spiking activity recorded in sham rats during cue sampling was related to both reward magnitude and reward identity, with higher firing rates observed for cues that predicted more reward. Lesioned rats also showed differential activity to the cues, but this activity was unbiased towards larger rewards. These data support a role for OFC in shaping activity in the ventral striatum to represent the biological significance of associative information in the environment.

0 件のコメント:

コメントを投稿