Involvement of the medial prefrontal cortex in two alternation tasks using different environments

Area of Science:

• Neuroscience
• Cognitive Psychology
• Animal Behavior

Background:

• Spatial alternation is a key measure of working memory and behavioral flexibility.
• The T-maze is a standard tool for assessing spatial alternation.
• The medial prefrontal cortex (mPFC) plays a crucial role in executive functions.

Purpose of the Study:

• To investigate the impact of medial prefrontal cortex (mPFC) lesions on T-maze performance.
• To validate a novel alternation in a water maze (AWM) task.
• To compare the efficacy of the AWM and T-maze in assessing mPFC-dependent cognitive functions.

Main Methods:

• Selective bilateral lesions of the medial prefrontal cortex (mPFC) were induced in Sprague-Dawley rats via ibotenic acid microinjection.
• Control rats received vehicle injections.
• Performance was assessed using both a standard T-maze and a newly developed alternation in a water maze (AWM).

Main Results:

• Rats with mPFC lesions exhibited significant impairments in spatial alternation tasks.
• Performance deficits were observed in both the T-maze and the alternation in a water maze (AWM).
• Control rats performed significantly better than lesioned rats in both tasks.

Conclusions:

• The medial prefrontal cortex (mPFC) is essential for successful spatial alternation performance.
• The alternation in a water maze (AWM) is validated as a task dependent on frontal cortex function, probing working memory and behavioral flexibility.
• The AWM may offer advantages over the T-maze for cognitive research due to its potential for integration with other water maze tasks.