Neurotransmitters

Sample Solution

  The nigra striatal region of the brain is an important area for motor control. This area consists of different nuclei and pathways that are connected to many other parts of the brain, including the cortex, thalamus, and cerebellum. Two key neurotransmitters located in this region are dopamine and acetylcholine.    

Dopamine is a crucial neurotransmitter responsible for reward-seeking behavior, emotion regulation, movement control, and learning processes. It has been implicated in Parkinson’s disease due to reports that some people with this condition have low levels of dopamine in their brains. In addition to these roles, dopamine is also involved in controlling muscle movements through its projections from the substantia nigra to the spinal cord and on to structures such as the putamen. Studies have shown that lower dopamine activity can lead to changes in motor performance and decreased coordination abilities. Acetylcholine (ACh) is another essential neurotransmitter found within the nigra striatal region of the brain. Like dopamine, ACh plays a role in regulating motor behavior by projecting from its cell bodies located within this region onto both cortical areas as well as subcortical structures such as basal ganglia nuclei like globus pallidus interna (GPi). GPi neurons modulate movement commands issued by various cortical regions through inhibitory connections with thalamic relay cells that ultimately influence motor outputs from cortical areas via direct or indirect pathways back down onto spinal motoneurons through descending tracts like corticospinal tract (CST). Thus ACh released into these circuits serves both excitatory/inhibitory roles depending upon physiological context which helps fine tune complex behaviors like voluntary locomotion or finger tapping tasks which involve rapid activation/deactivation cycles across several muscles during coordinated movements. Overall it appears clear that both dopaminergic and cholinergic neurons play important roles in controlling muscle movements originating within nigral striatal circuitry extending outward into related downstream nerve networks comprising what we think of today as our neuromotor system capable of making sophisticated physical task orientations throughout our everyday lives!