Colchicine, a potent neurotoxin derived from plants, has been recently introduced as a degenerative toxin of small pyramidal cells in the cortical area 1 of the hippocampus (CA1). In this study, the effect of the alkaloid in CA1 on the behaviors in the conditioning task was measured. Injections of colchicine (1,5 μg/rat, intra-CA1) was performed in the male Wistar rats, while the animals were s...

BACKGROUND Fear conditioning is a traditional model for the acquisition of fears and phobias. Studies of the genetic architecture of fear conditioning may inform gene-finding strategies for anxiety disorders. The objective of this study was to determine the genetic and environmental sources of individual differences in fear conditioning by means of a twin sample. METHODS Classic fear conditio...

To explore the role of spinal cord plasticity in motor learning, we evaluated the effects of H-reflex operant conditioning on GABAergic input to rat spinal motoneurons. Previous work indicated that down-conditioning of soleus H-reflex increases GABAergic input to soleus motoneurons. This study explored the effect of H-reflex up-conditioning on GABAergic input. Of nine rats exposed to H-reflex u...

Consistent with the importance of the hippocampus in learning more complex stimulus relations, but not in simple associative learning, the dorsal hippocampus has commonly been implicated in classical fear conditioning to context, but not to discrete stimuli, such as a tone. In particular, a specific and central role in contextual fear conditioning has been attributed to mechanisms mediated by d...