Читать книгу The Behavior of Animals - Группа авторов - Страница 56

This processing stream originates in the small-celled system of the retina, passes the related structures of the diencephalic lateral geniculate nucleus, LGN, and reaches—via corresponding cortical areas V1-4—the integration and association fields of the inferior temporal cortex, ITC (Figure 2.11).

Figure 2.11 Visual processing streams in the primate cortex. Simplified diagram; bidirectional pathways not shown. LGN, lateral geniculate nucleus; V1-V5, visual cortical areas; ITC, inferior temporal cortex; PPC, posterior parietal cortex. (Compiled after data by Ungerleider & Mishkin 1982; Hubel & Livingstone 1987).

In area V1 the different orientations of contrast borders in terms of lines (|/\—) are determined by certain neurons arranged in columns as prerequisite for the analysis of combinations of lines and angles between them (L V ∧ T) explored in areas V2 and V3 (Hubel & Wiesel 1977). Shape and color are analyzed separately in layers of area V2 and are combined in V4, thus allowing assignments like “yellow banana.” Associations depend on connections with the hippocampus.

The ITC is involved in the recognition of gestures and postures, e.g., suitable for social communication. Neuronal responses selective to faces were discovered by Perrett and Rolls (1983) (Chapter 5). Comparable face-selective neurons were recorded in the temporal cortex of Dalesbred sheep: some neuron types preferring a conspecific’s face, others responding selectively to a German shepherd dog’s face (Kendrick 1994). It is suggested that an assembly of differently face-tuned neurons code for the recognition of an individual face (cf. Cohen & Tong 2001).