The Effect of Neurotransmission on Human Behavior

1. 2: Using one or more examples, explain effects of neurotransmission on human behavior: Our nervous systems consist of between 10 to 100 billion neurons; each of which making 13 trillion connections with each other through electrochemical messages that allow people to respond to stimuli, from the environment or from internal changes in a person’s body. The neurons send these electrochemical messages through neurotransmission.

Electrical impulses traveling down the axon (body) of a neuron, instigates the release of neurotransmitters, which travel over the synapse, which is the gap between two neurons. Once the neurotransmitters cross the synapse, they go into receptor sites on the post-synaptic membrane of a neuron, and after having passed on the message, they are either broken down or reabsorbed by the terminal buttons of the neuron, in a process known as reuptake. Neurotransmission has been shown to affect a large range of human behaviors.

Serotonin is a neurotransmitter that effects sleep, arousal levels, and emotion. In a 1999 study at Tokyo University, its effects were seen. Kasamatsu and Hirai conducted this study in order to examine the way that sensory deprivations affects the brain. They studied a group of monks going on a 72-hour pilgrimage without food or water. The monks endured the weather without shelter from the cold, and didn’t speak among themselves. Two thirds of the way through the pilgrimage, the hallucinations began, taking the shape of ancient ancestors, or just a presence at their side.

Blood samples, taken immediately after the monks reported their hallucinations, were compared to blood samples taken prior to the pilgrimage, and showed increased serotonin levels. These increased serotonin levels activated the hypothalamus and the frontal cortex, causing the monk’s hallucinations. Kasamatsu and Hirai were able to conclude that sensory deprivation caused increase in serotonin levels, which altered the monks’ perception and behavior. Neurotransmitters, like serotonin, can play a large role in human behavior.

However, it is considered reductionist to rely solely on them to explain human behavior; they only play a role and can’t be held fully responsible for behavior. Research and increased knowledge of neurotransmission has led to the development of drugs that can either simulate a neurotransmitter in the case of a deficiency, or block a receptor site if there are excessive neurotransmitters. Understanding how neurotransmitters can affect behavior has led to the development of these drugs, which have helped many people.