Kovács G, Vogels R, Orban G A
Laboratorium voor Neuro-en Psychofysiologie, Katholieke Universiteit te Leuven, Belgium.
Proc Natl Acad Sci U S A. 1995 Jun 6;92(12):5587-91. doi: 10.1073/pnas.92.12.5587.
The perception of a briefly presented shape is strongly impaired when it is followed by another pattern, a phenomenon called backward masking. We found that the vast majority of a sample of shape-selective neurons in the macaque inferior temporal cortex respond selectively to backward-masked shapes, although these shapes could not be discriminated by human and monkey subjects. However, this selective response was brief, since it was either interrupted by the mask or overridden by a response to the mask itself. We show that reliable discrimination of briefly presented shapes by single neurons depends on the temporal integration of the response. Presentation of the mask, however, reduces the number of spikes available for integration, explaining backward masking. These results also provide direct neurophysiological evidence for the "interruption theory" of backward masking.
当一个短暂呈现的形状之后紧接着出现另一个图案时，其感知会受到严重损害，这种现象被称为后向掩蔽。我们发现，猕猴颞下皮质中绝大多数形状选择性神经元样本对后向掩蔽的形状有选择性反应，尽管人类和猴子受试者无法辨别这些形状。然而，这种选择性反应很短暂，因为它要么被掩蔽中断，要么被对掩蔽本身的反应所取代。我们表明，单个神经元对短暂呈现形状的可靠辨别取决于反应的时间整合。然而，掩蔽的呈现减少了可用于整合的尖峰数量，从而解释了后向掩蔽现象。这些结果也为后向掩蔽的“中断理论”提供了直接的神经生理学证据。
