傳感神經(jīng)元能夠預(yù)測(cè)動(dòng)物即將做出的決定的能力在過(guò)去十年里激起人們巨大興趣,，人們關(guān)于這些神經(jīng)元的活動(dòng)會(huì)以某種方式促成正確決策的印象比以前更深了。
在一項(xiàng)涉及在一個(gè)基于視頻的雙眼像差辨別任務(wù)中讓猴子做出選擇的研究中,，Hendrikje Nienborg 和 Bruce Cumming發(fā)現(xiàn),，這一模型過(guò)于簡(jiǎn)單,。他們的數(shù)據(jù)顯示了一個(gè)相反方向的因果關(guān)系：一旦一個(gè)決定被做出，這個(gè)決定本身將改變傳感神經(jīng)元的反應(yīng),。關(guān)于要看什么的決定會(huì)主動(dòng)地改變所看到的東西,。（生物谷Bioon.com）
生物谷推薦原始出處：
Nature 459, 89-92 (7 May 2009) | doi:10.1038/nature07821
Decision-related activity in sensory neurons reflects more than a neuron's causal effect
Hendrikje Nienborg1 & Bruce G. Cumming1
Laboratory of Sensorimotor Research, National Eye Institute, National Institutes of Health, 49 Convent Drive, Bethesda, Maryland 20892, USA
During perceptual decisions, the activity of sensory neurons correlates with a subject's percept, even when the physical stimulus is identical1, 2, 3, 4, 5, 6, 7, 8, 9. The origin of this correlation is unknown. Current theory proposes a causal effect of noise in sensory neurons on perceptual decisions10, 11, 12, but the correlation could result from different brain states associated with the perceptual choice13 (a top-down explanation). These two schemes have very different implications for the role of sensory neurons in forming decisions14. Here we use white-noise analysis15 to measure tuning functions of V2 neurons associated with choice and simultaneously measure how the variation in the stimulus affects the subjects' (two macaques) perceptual decisions16, 17, 18. In causal models, stronger effects of the stimulus upon decisions, mediated by sensory neurons, are associated with stronger choice-related activity. However, we find that over the time course of the trial these measures change in different directions—at odds with causal models. An analysis of the effect of reward size also supports this conclusion. Finally, we find that choice is associated with changes in neuronal gain that are incompatible with causal models. All three results are readily explained if choice is associated with changes in neuronal gain caused by top-down phenomena that closely resemble attention19. We conclude that top-down processes contribute to choice-related activity. Thus, even forming simple sensory decisions involves complex interactions between cognitive processes and sensory neurons.
