Human behavior is determined by the interplay of several factors; individual genes and the environment are some of the leading factors in determining personal traits and tendencies. However, although inheritance and the environment play the greater role in determining an individual’s behavior, hormones as well as neurotransmitters also play crucial roles in shaping one’s behavior. Some hormones, for example, are linked with controlling anger and aggression in both men and women, while other sets of hormones are linked with the control of sleep. Hormonal imbalances are also linked with the control of individual temperaments. Hormones exert their control on human behavior through the messages that they deliver to particular parts of the body. Neurotransmitters, on the other hand, affect human behavior through directly influencing neurons within specific locations inside the brain. The abnormal release of some neurotransmitters is also linked with the mental disorders.
Hormones, in simple terms, refer to chemical messengers released directly into the blood from various glands located within the body. They are released in minute amounts, and it only takes small amounts to bring major adjustments into the body (Pfaff, Arnold and Etgen 698). For example, the over secretion or deficiency of some hormones can lead to diseases. Hormones play multiple roles, ranging from regulating metabolism to controlling the reproductive cycle. Other hormones regulate mood swings, thus, influencing human behavior. One of the main hormones that affect human behavior is testosterone.
Testosterone is a hormone produced within the body and is responsible for the growth and development of sexual organs in males. It is also responsible for maintaining other sexual characteristics in males. Normally, testosterone is produced within the testes, and its production is regulated by the pituitary and hypothalamus glands. Studies suggest that testosterone plays a role in promoting aggressive behavior. This occurs when the hormone is in both low and high levels. However, the dynamics that influence the aggression behavior is still not clear (Blakemore, Berenbaum and Liben 166).
The fluctuations in testosterone level also affect emotional well being. A healthy human being a “normal” range of testosterone levels in order to maintain a healthy mental wellbeing. Low levels of the hormone have been associated with mood disorders as well as depression. Low levels can also lead to hyper-excitability. In some cases, the fluctuations in testosterone levels can lead to suicidal thoughts.
Testosterone also influences human behavior by affecting functions of the brain. Some brain functions such as memory retention, spatial awareness, attention and concentration span are under the influence of testosterone. Low levels of testosterone, for example, are associated with impaired cognitive ability and degenerating conditions such as Alzheimer’s and dementia. In some cases, it is necessary to top up the hormone levels to avoid those degenerating conditions.
Elevated levels of testosterone are associated with the desire for dominance. However, the desire for dominance should not be confused with aggression. Some studies indicate that although there is a correlation between high testosterone levels and aggression, the relationship is a weak one. The desire for dominance can complement other traits such as competitiveness and willingness to take a risk. Nevertheless, the high testosterone cannot be used as the single predictor of male behavior; however, it can give a clue about the likelihood of some people to take part in risky and fearful adventures.
Apart from hormones, neurotransmitters are the other chemical components that play a role in determining human behavior. Neurotransmitters are chemical substances that transmit chemical messages from neurons to specific cells of the body. After an action potential reaches a synapse, the neurotransmitter is released from the axon; it then attaches itself to the receptor site after crossing the synaptic gap.
Depending on the type, neurotransmitters influence the message send by the neuron. For example, excitatory neurotransmitters excite neurons. Therefore, the presence of these neurotransmitters is likely to trigger excitement and feel-good effects on an individual. Such neurotransmitters include epinephrine, acetylcholine and norepinephrine. The other types of transmitters are largely inhibitory, and their presence is likely to decrease the likelihood of firing an action potential (Coon and Mitterer 51). Such neurotransmitters include gamma aminobutyric acid (GABA), serotonin and dopamine. The release of these neurotransmitters is likely to trigger sadness and uninspiring mood in individuals (Coon and Mitterer 51). The normal balance of neurotransmitters is changed by the intake of substances such as cocaine, marijuana, alcohol and other drugs. This imbalance causes changes in mood and behavior of the person taking the drug. Every neurotransmitter is found in specific parts of the brain.
One of the important neurotransmitters that influence human behavior is epinephrine. It is generally found within the central nervous system and in the adrenal medulla (within the chromaffin cells). In terms of affecting human behavior, epinephrine is associated with feelings of well-being and happiness. It also has a host of other functions including regulating heart rate and metabolic shifts.
Epinephrine is a natural energy booster, and it enables individuals to respond adequately to situations of danger or pressure. For example, when faced by a dangerous animal such as a lion, the release of epinephrine makes the individual outrun the dangerous animal. Its secretion is under the control of the adrenal medulla. The release of the neurotransmitter is normally triggered by physical and mental stress. When released, epinephrine causes an increase in the rate of heart beat and an increase in blood sugar; these adjustments, in turn, increase the metabolic rate within the individual resulting into the production of vast amounts (Brannon and Feist 99).
However, frequent release of epinephrine causes the body to be in a continuous state of energy, which is detrimental to one’s health. This occurs because such a state predisposes the brain to process stimuli, thus, causing the brain to tire continuously. In addition, individuals used to high energy activities are vulnerable to epinephrine withdrawal, which, in effect, causes irritability, restlessness and panic attacks – in the extreme cases (Brannon and Feist 99).
In conclusion, the influence of hormones and neurotransmitters on human behavior cannot be underestimated. Hormones, for example, alter individual moods and shape an individual’s desire to dominate. High testosterone levels, for instance, are associated with the desire for dominance. Neurotransmitters, on the other hand, trigger excitement or feelings of low self-esteem depending on the neurotransmitter released. Epinephrine, for instance, is associated with feelings of excitement and vigor while other inhibitory neurotransmitters such as serotonin are associated with feelings of low self-esteem. However, the imbalance of both hormones and neurotransmitters in the body can be detrimental to one’s health. In some cases, such imbalances lead to mental disorders such as depression, Alzheimer’s disease and dementia.
Blakemore, Judith E. Owen, Sheri A. Berenbaum and Lynn S. Liben. Gender Development.
London : Psychology Press, 2008. Print.
Brannon, Linda and Jess Feist. Health Psychology: An Introduction to Behavior and Health.
Stamford, CT : Cengage , 2009. Print.
Coon, Dennis and John Mitterer. Introduction to Psychology: Gateways to Mind and Behavior.
Stamford, CT : Cengage , 2008. Print.
Pfaff, Donald W., et al. Hormones, Brain and Behavior, Volume 5. Waltham, MA : Academic
Press, 2002. Print.