This week included an excursion to the ANI research infrastructure. ANI research infrastructure houses four brain imaging laboratories: TMS, fMRI and MEG, as well as a behavioral laboratory with EEG. The TMS systems at AMI Centre allow for navigated and repeated stimulus administration. One of the main things TMS is used for is mapping the motor cortex. The behavioral laboratory had multiple devices for behavioral studies, such as a heat camera, eye tracking device and a galvanic skin response measurement device. In the behavioral laboratory are performed multiple different types of experiments, e.g. studying EEG responses and eye movements in cognitive tasks requiring attention and memory. While fMRI sets some limitations to what can be done, it has been used to study brain responses caused by both visual and auditory stimuli in different experimental settings involving emotional and cognitive processing.
The topic of this week’s lecture was about the motor systems. Motor systems are combinations of peripheral (muscles and nerves connecting to muscles) and central structures that work together to support movement. Central structures that are part of the motor system are cerebral cortex, brain stem, spinal cord, cerebellum, lower and upper motor neurons and pyramidal system. Central structures are referred as a central motor system which has a hierarchy of control levels. The hierarchy can be divided into three levels. The first and the highest of the hierarchy levels contain association areas of neocortex and basal ganglia of the forebrain. The second level, middle level, contains cerebellum and and the motor cortex. Last level, and lowest in the hierarchy includes brain stem and the spinal cord. Three levels are separated by their function. In the first level the strategy of the movement is produced the second level processes the tactics of the movement, which muscles should activated and the sequence of the contractions. The third level is responsible in the execution of the movement.