There is considerable debate about whether differential delay eyeblink conditioning can be acquired without awareness of the stimulus contingencies. Previous investigations of the relationship between differential-delay eyeblink conditioning and awareness of the stimulus contingencies have assessed awareness after the conditioning session was finished using a post-experimental questionnaire. In two experiments, the point at which contingency awareness developed during the conditioning session was estimated from a button-press measure of expectancy of the unconditioned stimulus (US). In both experiments, knowledge of the stimulus contingencies and acquisition of differential delay eyeblink conditioning developed approximately in parallel. In Experiment 1 it was shown that predicting the US facilitated eyeblink conditioning compared with predicting the eyeblink response. In Experiment 2, a masking task was used that slowed down the emergence of awareness, and it was shown that differential conditioning only occurred in participants who were able to predict the US. The current findings challenge the hypothesis that differential delay eyeblink conditioning is entirely mediated by a functionally and neurally distinct nondeclarative learning system.
We investigated the role of cholinergic neurotransmission in olfactory fear learning. Mice receiving pairings of odor and foot shock displayed fear to the trained odor the following day. Pretraining injections of the nicotinic antagonist mecamylamine had no effect on subsequent freezing, w ... mehr
In Aplysia, repeated trials of aversive stimuli produce long-term sensitization (LTS) of defensive reflexes and suppression of feeding. Whereas the cellular underpinnings of LTS have been characterized, the mechanisms of feeding suppression remained unknown. Here, we report that LTS traini ... mehr
The anaphase promoting complex/cyclosome (APC/C) is an E3 ligase regulated by Cdh1. Beyond its role in controlling cell cycle progression, APC/C–Cdh1 has been detected in neurons and plays a role in long-lasting synaptic plasticity and long-term memory. Herein, we further examined the role ... mehr