Differential effects of excitotoxic lesions of the basolateral amygdala, ventral subiculum and medial prefrontal cortex on responding with conditioned reinforcement and locomotor activity potentiated by intra-accumbens infusions of D-amphetamine

Behav Brain Res. 1993 Jun 30;55(2):167-83. doi: 10.1016/0166-4328(93)90113-5.


The experiments reported here have investigated the impact on reward-related processes of lesioning the basolateral amygdala, ventral subiculum and prelimbic cortex which represent the major limbic sources of afferents to the ventral striatum. The results showed that, while lesions of the prelimbic cortex were without effect on the approach to a CS predictive of sucrose reinforcement and the acquisition of a new response with conditioned reinforcement, lesions of the other two structures significantly impaired both responses. However, there were important differences between the effects of basolateral amygdala and ventral subiculum lesions. Thus, lesions of the ventral subiculum completely abolished the locomotor response to intra-accumbens infusions of D-amphetamine, in addition to blocking the potentiative effect of the same treatment on responding with conditioned reinforcement. Lesions of the basolateral amygdala, by contrast, reduced the control over behaviour by a conditioned reinforcer, but not the potentiation of that control by intra-accumbens D-amphetamine except at the highest dose. Moreover, the locomotor response to D-amphetamine-induced increases in dopamine in the nucleus accumbens was unaffected by amygdala lesions over the dose range blocked by ventral subiculum lesions. The results suggest a rather selective effect of amygdala-ventral striatal interactions on processes subserving conditioned reinforcement and a more fundamental influence of ventral subiculum-ventral striatal interactions in mediating the psychomotor stimulant effects of D-amphetamine.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Afferent Pathways / drug effects
  • Afferent Pathways / physiology
  • Amygdala / drug effects
  • Amygdala / physiology*
  • Animals
  • Arousal / drug effects
  • Arousal / physiology*
  • Association Learning / drug effects
  • Association Learning / physiology
  • Brain Mapping
  • Conditioning, Classical / drug effects
  • Conditioning, Classical / physiology*
  • Dextroamphetamine / pharmacology*
  • Dominance, Cerebral / drug effects
  • Dominance, Cerebral / physiology
  • Dopamine / physiology
  • Efferent Pathways / drug effects
  • Efferent Pathways / physiology
  • Hippocampus / drug effects
  • Hippocampus / physiology
  • Limbic System / drug effects
  • Limbic System / physiology*
  • Male
  • Motivation*
  • Motor Activity / drug effects
  • Motor Activity / physiology*
  • Nucleus Accumbens / drug effects
  • Nucleus Accumbens / physiology*
  • Prefrontal Cortex / drug effects
  • Prefrontal Cortex / physiology*
  • Quinolinic Acid / pharmacology
  • Rats
  • Reinforcement Schedule


  • Quinolinic Acid
  • Dextroamphetamine
  • Dopamine