Department of Technology, Computational Neuroscience, Institució Catalana de Recerca i Estudis Avançats, Universitat Pompeu Fabra, 08018 Barcelona, Spain.
Proc Natl Acad Sci U S A. 2010 Apr 20;107(16):7545-9. doi: 10.1073/pnas.1002333107. Epub 2010 Apr 1.
During decision making between sequential stimuli, the first stimulus must be held in memory and then compared with the second. Here, we show that in systems that encode the stimuli by their firing rate, neurons can use synaptic facilitation not only to remember the first stimulus during the delay but during the presentation of the second stimulus so that they respond to a combination of the first and second stimuli, as has been found for "partial differential" neurons recorded in the ventral premotor cortex during vibrotactile flutter frequency decision making. Moreover, we show that such partial differential neurons provide important input to a subsequent attractor decision-making network that can then compare this combination of the first and second stimuli with inputs from other neurons that respond only to the second stimulus. Thus, both synaptic facilitation and neuronal attractor dynamics can account for sequential decision making in such systems in the brain.
在对连续刺激进行决策时，第一个刺激必须在记忆中保持，然后与第二个刺激进行比较。在这里，我们表明，在通过发射率对刺激进行编码的系统中，神经元不仅可以在延迟期间利用突触易化来记住第一个刺激，而且可以在呈现第二个刺激期间利用突触易化来记住第一个刺激，从而对第一个和第二个刺激的组合做出反应，这与在进行振动频率决策时记录的腹侧运动前皮层中的“偏微分”神经元的发现是一致的。此外，我们表明，这种偏微分神经元为随后的吸引子决策网络提供了重要的输入，该网络可以将第一个和第二个刺激的这种组合与仅对第二个刺激做出反应的其他神经元的输入进行比较。因此，在大脑中的这些系统中，突触易化和神经元吸引子动力学都可以解释连续决策。
