Functional Localization in the Nucleus Rotundus,
Abstract
Work has suggested that the effects of psychoactive drugs on visual performance may best be understood, and/or predicted, by studying differential effects of the drugs on functionally differentiated sets of neurones in visual projection systems in the brain. This study demonstrates that the nucleus rotundus, an avian posterior thalamic visual relay nucleus homologous to parts of the mammalian lateralis posterior/pulvinar complex, is divided into at least three functionally distinct neurone subsets. The 'posterior' rotundal cells respond to any moving retinal image. Ventral rotundal cells respond preferentially to intensity modulation of moving or stationary stimuli. Anterior rotundal neurones respond preferentially to such abstract properties of moving stimuli as size, velocity, and direction of movement. All subnuclei may be further subdivided by function. The findings reinforce current theories which suggest that pattern vision results from cortical integration of the outputs of many classes of pattern selective visual projection system neurones. Preliminary findings are also presented suggesting that effects of psychoactive drugs, such as ethanol, can indeed be predicted or understood by studies on differential effects on neurones in this model system.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 1977
- Accession Number
- ADA047717
Entities
People
- Alvin M. Revzin
Organizations
- Federal Aviation Administration