| Description |
Two views are posed against each other concerning the acquisition of motor sequences. One side views motor sequence learning as a form of sensory-motor learning where the striatum associates sensory information with the proper motor movement. Support for this theory is found in animal studies where disruption of the striatum impairs sequential movements. The other side believes that non-declarative memory is important to acquiring sequences. Their argument is based on Squire's (1987) declarative versus non-declarative memory system. In support of Squire's model are studies showing that the hippocampus is associated with declarative memory. For example, amnesics cannot learn new facts or recall recent events, but can acquire new motor tasks. Also supporting Squire's model are studies on people with striatal damage from Huntington's disease. These patients can recall new facts but cannot learn novel motor skills. This study tests both theories by utilizing a declarative version of a sequential task. It also examines the performance of hippocampal lesioned animals to further test Squire's theory. Four groups of rats are used: striatal, hippocampal, striatal sham, and hippocampal control lesioned. Each group is given 40 trials to learn the sequence. All groups learn it except the hippocampal group who have have the most retrospective errors. The successful groups run 40 more trails on the same sequence albeit 1 novel arm replaces 1 original arm. Striatal sham animals demonstrate more learning flexibility |
