Measuring emotional memory in the elevated T-maze using a training-to-criterion procedure

Area of Science:

• Neuroscience
• Behavioral Pharmacology
• Cognitive Science

Background:

• The elevated T-maze is an ethologically relevant test for assessing anxiolytic drug effects on memory.
• Anxiolytic drugs may impair memory through insufficient learning or direct amnesia.
• Distinguishing between learning deficits and memory impairment is crucial for understanding drug effects.

Purpose of the Study:

• To investigate if a multitrial training-to-criterion procedure can differentiate between learning and memory deficits induced by anxiolytic drugs.
• To evaluate the effects of diazepam (DZP) on inhibitory avoidance learning and memory using this refined protocol.

Main Methods:

• Rats were trained on the elevated T-maze using a multitrial procedure until they reached a specific learning criterion (300s in the enclosed arm).
• Experiment 1 assessed retention performance after criterion training.
• Experiment 2 administered diazepam (DZP) before training to evaluate its effects on acquisition and memory recall.

Main Results:

• Training to a learning criterion significantly improved retention performance compared to standard training.
• Diazepam (DZP) did not impair avoidance learning acquisition but dose-dependently impaired inhibitory avoidance memory recall.
• Diazepam did not affect one-way escape response latency.

Conclusions:

• The multitrial training-to-criterion protocol effectively distinguishes between learning and memory processes.
• Diazepam's disruptive effects in the elevated T-maze are related to memory consolidation, not initial learning.
• These findings support the hypothesis that anxiolytic drugs interfere with long-term information storage.