Putamen - Function: Motor Skills

Function: Motor Skills

While the putamen has many functions, it has been concluded that it has no specific specialization. However, since the putamen is interconnected with so many other structures, it works in conjunction with them to control many types of motor skills. These include controlling motor learning, motor performance and tasks, motor preparation, specifying amplitudes of movement, and movement sequences.

Some neurologists hypothesize that the putamen also plays a role in the selection of movement (e.g. Tourette Syndrome) and the "automatic" performance of previously learned movements (e.g. Parkinson's disease).

In one study it was found that the putamen controls limb movement. The goal of this study was to determine whether particular cell activity in the putamen of primates was related to the direction of limb movement or to the underlying pattern of muscular activity. Two monkeys were trained to perform tasks that involved the movement of loads. The tasks were created so that movement could be distinguished from muscle activity. Neurons in the putamen were selected for monitoring only if they were related both to the task and to arm movements outside the task. It was shown that 50% of the neurons that were monitored were related to the direction of movement, independent of the load.

Another study was done to investigate movement extent and speed using PET mapping of regional cerebral blood flow in 13 humans. Movement tasks were performed with a joystick-controlled cursor. Statistical tests were done to calculate the extent of movements and what regions of the brain the movements correlate to. It was found that "increasing movement extent was associated with parallel increases of rCBF in bilateral basal ganglia (BG; putamen and globus pallidus) and ipsilateral cerebellum." This not only shows that the putamen affects movement but it also shows that the putamen integrates with other structures in order to perform tasks.

One study was done in order to specifically investigate how the basal ganglia influences the learning of sequential movements. Two monkeys were trained to press a series of buttons in sequence. The methods used were designed to be able to monitor the well-learned tasks versus the new tasks. Muscimol was injected into various parts of the basal ganglia, and it was found that "the learning of new sequences became deficient after injections in the anterior caudate and putamen, but not the middle-posterior putamen." This shows that different areas of the striatum are utilized when performing various aspects of the learning of sequential movements