All neurotransmitters are essential for the organisation of the body system, as they are chemicals through which neurons communicate. Neurons are specialised cells of the nervous system specialised cells that bring sensory information to the brain and perform other functional roles such as the processing of thoughts, actions, memories and behaviours (Martin, Carlson, Buskist, 2010). The communication between neurons is are essential to maintain these functions, which is why involvement of neurotransmitters concerning this process cannot be ignored. This essay will focus on the role of dopamine, a neurotransmitter in the central nervous system (CNS) that consists of the brain and the spinal cord. The psychological importance of dopamine in the human behavioural, emotional, cognitive and physical processes will be discussed, using examples of direct measurements and manipulations from ranges of empirical studies.
Given the location of dopamine in the CNS, its main function relates to the organisation of the brain. So far, three major dopaminergic pathways have been discovered in the CNS. The first, mesolimbic pathway, runs from group of cell in the midbrain to other parts of the limbic system, nucleus accumenbens, amygdala and frontal cortex. The second, nigrostriatal pathway, consists of cells in the substantia nigra and basal ganglia, terminating in the corpus striatum. Lastly, the tuberohypophyseal system runs through the hypothalamus to the pituitary gland. The role of dopamine in relation to these pathways will be examined in the below paragraphs (Rang & Dale, 2007).
It has been established that dopamine plays a critical role in the human behaviour processes. The imbalances of dopamine in the mesolimbic pathway has been linked to psychological disorders such as Attention Deficit Hyperactivity Disorder (ADHD) and schizophrenia,
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