Stimulus-specific long-term habituation of visually guided orienting behavior toward prey in toads: a 14C-2DG study

J Comp Physiol A. 1988 May;163(1):1-11. doi: 10.1007/BF00611991.


The regional distribution of cerebral glucose utilization, revealed by the 14C-2DG technique, was compared between (i) toads after stimulus-specific long-term habituation of the orienting response toward a repeatedly presented prey dummy ('habituation group') and (ii) non-habituated toads, readily orienting toward the repetitively presented prey stimulus ('naive group'). In the 'habituation group', the ventral medial pallium (vMP), a certain portion of the preoptic area (PO), and the dorsal hypothalamus (dHYP) showed a statistically significant increase in 14C-2DG-uptake; decrease was observed in the ventral layers of the optic tectum (vOT), a portion of the tegmental reticular formation (RET), the ventral cerebellum (vCB), and the striatum (STR). The results suggest that stimulus-specific long-term habituation of prey-catching affects both, components of the stimulus-response mediating circuit (e.g., involving OT), and structures extrinsic to it, (e.g., vMP, PO, dHYP), which may belong to a modulatory circuitry. Bilateral lesions to vMP strongly delay habituation. Our results are suggesting that damping of the adequate behavioral motor response during habituation involves active inhibitory processes of a modulatory system that develops in strength during stimulus repetition so as to suppress response output, which basically supports Sokolov's hypothesis (1975).

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Appetitive Behavior / physiology*
  • Autoradiography
  • Bufo bufo / physiology*
  • Carbon Radioisotopes
  • Cerebellum / anatomy & histology
  • Cerebellum / metabolism
  • Cerebral Cortex / anatomy & histology
  • Cerebral Cortex / metabolism
  • Diencephalon / anatomy & histology
  • Diencephalon / metabolism
  • Habituation, Psychophysiologic / physiology*
  • Mesencephalon / anatomy & histology
  • Mesencephalon / metabolism
  • Orientation / physiology*
  • Photic Stimulation*
  • Predatory Behavior / physiology*
  • Telencephalon / anatomy & histology
  • Telencephalon / metabolism


  • Carbon Radioisotopes