2013年6月25日火曜日

Prefrontal mechanisms of behavioral flexibility, emotion regulation and value updating

Peter H Rudebeck, Richard C Saunders, Anna T Prescott, Lily S Chau & Elisabeth A Murray
Nature Neuroscience (2013) doi:10.1038/nn.3440
Received 20 March 2013 Accepted 21 May 2013 Published online 23 June 2013

OFC(眼窩前頭前野)とその周辺を損傷すると、失敗しても行動を変えない、ヘビを怖がらない、食べ飽きたモノを選び続けてしまう、ことなどが知られていた。しかし、OFC「だけ」を厳密に損傷したサルでは三つ目のみが観察された。

つまり、OFCの本質的な機能は「自分の状態(例:ある食べ物に飽きた)に合わせて、選択肢の価値を変える」こと。
「これまでの研究が不注意でOFC以外の部分にもダメージを与えていた可能性を検証する」とか、けっこうきついことが書いてあるw

Two ideas have dominated neuropsychology concerning the orbitofrontal cortex (OFC). One holds that OFC regulates emotion and enhances behavioral flexibility through inhibitory control. The other ascribes to OFC a role in updating valuations on the basis of current motivational states. Neuroimaging, neurophysiological and clinical observations are consistent with either or both hypotheses. Although these hypotheses are compatible in principle, we present results supporting the latter view of OFC function and arguing against the former. We found that excitotoxic, fiber-sparing lesions confined to OFC in monkeys did not alter either behavioral flexibility, as measured by object reversal learning, or emotion regulation, as assessed by fear of snakes. A follow-up experiment indicated that a previously reported loss of inhibitory control resulted from damage to nearby fiber tracts and not from OFC dysfunction. Thus, OFC has a more specialized role in reward-guided behavior and emotion than has been thought, a function that includes value updating.

0 件のコメント:

コメントを投稿