The investigator studied the effects of ethanol on the spontaneous activity of single neurons in functionally differentiated subnuclei of a posterior thalamic visual projection area, nucleus rotundus, in the anesthetized pigeon. Low doses of ethanol, 0.05 - 0.10 ml/kg (producing blood levels of about 0.005 - 0.010%) , inhibited activity in anterior rotundus but had complex excitatory-inhibitory effects on posterior rotundal cells. Nonvisual dorsal thalamic cells, and 'lateral geniculate' neurons were inhibited by ethanol but threshold doses (0.25 - 0.40 ml/kg) were far higher than those for the rotundal cells (0.05 ml/kg). These differing dose-response curves for visual and nonvisual thalamic neurons suggest: (1) low doses of ethanol may seriously impair peripheral visual functions; (2) The behavioral effects of ethanol are highly dose-dependent; (3) Effects of low doses of ethanol may not be extrapolated from high-dose effects since high-dose effects may 'mask' effects dominant at low doses; (4) The effects of a given dose of ethanol may vary widely and unpredictably among individuals. Thus, the notorious unpredictability of ethanol-induced changes in behavior or task performance may be the inevitable consequence of the reported differential dose-response effects on single neurons.

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  • Pagination: 12 p.

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Filing Info

  • Accession Number: 00175515
  • Record Type: Publication
  • Source Agency: National Technical Information Service
  • Report/Paper Numbers: FAA-AM-78-2
  • Files: NTIS, USDOT
  • Created Date: May 31 2002 12:00AM