Introduction: T-mazes provide a valid way to study the working memory and hippocampal function of an animal, especially rats.
- Spontaneous alteration: When two trials are given in quick succession, the rat spontaneously chooses the arm not visited before.
- Rewarded alteration: Reinforcing the rat's spontaneous alteration with a food reward.
- Typical spontaneous alternation rates are around 75%.
Working memory vs. Reference memory:
- A working memory task involves the rat remembering what he has just done (i.e. altering between sides of the T-maze).
- A reference memory task involves learning a rule that does not change (i.e. run down the white side of the maze) regardless of whether it is left or right.
- A rat learns reference memories in about 40 trials.
- Rats naturally alternate, and can be given food rewards for alternation.
- Detects more subtle changes than the Morris Water Maze.
T-maze vs. Y-maze:
- T-maze has discrete trials. Y-maze has continuous trials.
- T-maze has less variance in trial time. Y-maze has more variance in trial time.
- T-maze has more human interference/animal handling. Y-maze has no human interference/animal handling.
- Alternation rates are lower in the Y maze (~65%).
- Rats with hippocampus removed adopt side preferences, and will still score highly in a continuous trials procedure.
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