The Psychobehavioral Roles of One Neurotransmitter - Essay Example

Running Head: Neurotransmitter and psychoactive drugs Neurotransmitter and psychoactive drugs Name Institution Date Neurotransmitter and psychoactive drugs Question: Briefly describe the psychobehavioural roles of ONE neurotransmitter and discuss how the effects of psychoactive drugs support these notions. Effects of psychoactive drugs have been studied extensively partly because of their effects on human beings. However literature is limited on the underlying mechanisms and their effects on neurotransmission and the resultant psychobehaviour tendencies. This may be attributed to the fact that most studies have often focused majorly on individual drugs-their pharmacokinetics, and their corresponding physiological effects-or on the indivudual’s social impact. The paper is structured as follows: the first part is a general introduction followed by conceptualization of the key terms. The third section is the body which focuses mainly on the subject matter. This will be followed by conclusion drawn from the rest of the body. Definition of key concepts: Psychobehaviours, neurotransmitters and psychoactive drugs Psychobehaviours can be simply described to mean those aspects or elements of behaviours attributed to some psychological causes or importance. On the other hand, the term Neurotransmitters simply include those substances or matter found at the nerves endings which coordinates with adjacent nerves by way of impulses or messages The neurons send electrochemical messages to the brain so that we can respond to stimuli – either from the environment or from internal changes through neurotransmission. Psychoactive drugs are a generally chemical-based substance which interferes with the function of the brain thus leading to temporary changes in individual’s behavior, mood, and sensory perception, thought process (Ayala, 2009:259). Neurotransmitter directly or indirectly influences neurons in a specific portion of the brain, hence leading to a behavioural response however, abnormal levels in neurotransmitters is often associated with mental disorders. A case in point is serotonin which plays a regulatory role of the various physiological functions including sensory functions, mood, as well as secretion of some hormones. In addition, this neurotransmitter is also responsible for other psycho-behavioural tendencies like anxiety and depression (Ayala, 2009:259). The same sentiment is also shared by Ouchi and his colleques who argue that some of these psycho-behavioural disturbances are closely attributed to disruption or interference of the serotonergic system specifically through the loss of neurons in the serotonergic raphe nuclei as well as dysfunction of its nerve terminals in the neocortex (Ouchi et al., 2009: 1260). Serotonin is usually produced from serotonergic varicosities into the extracellular space and tends to triggers serotonin found on the cells of target neurons. This then links or coordinates the resultant effects of serotonin as the endogenous ligand and of broad variety of both pharmaceutical and psychoactive drugs. The process inactivation of serotonin usually starts with Reuptake (Ouchi et al., 2009; 260). A large number of serotonergic neurons are found at the foot of the brain and is associated with such brain processes like attention, emotion, and motivation. The nerve endings or neurons extend to various part of the brain in order to perform various functions. Some of the areas worth noting are the amygdale responsible for the controlling emotions. The second part is the accumbens which controls motivation to engage in some behaviors, for instance drug abuse (Lovinger, 1999:23). So how does psychoactive drug affects neurotramitters? These drugs generally impacts on neurotransmitters by interfering with the way neurotransmitter affects the cell. This drug does this by either blocking or even producing too many impulses (Ciccarelli and White, 2009). As a result of this, the normal transmission of impulses from one membrane to another is interrupted. This drug also hinders or affects the normal functions of neurotransmitter structure, for instance the serotonergic system. This can be illustrated though various steps but not limited to transmitter synthesis, postsynaptic action, inactivation, as well as reuptake. More details are presented in the next section. Fenfluramine and Fluoxetine drugs These two drugs are known to interfere with the normal brain functioning in various ways. Fenfluramine usually lower serotonin levels in the brain but instead enhances its main metabolite, 5-HIAA. This usually takes place some times after administration. This is usually followed by an increased production of serotonin from nerve terminals and consequently an increased activity within the serotonergic system. On the other hand, Fluoxetine, is thought to increases in extracellular serotonin concentration and therefore an increase in the serotonergic system in different regions of the forebrain, for instance in both the diencephalon as well as the striatum. The effects of these drugs are able to work on particular enzyme or protein to trigger or induce loss of serotonergic neurons and decrease serotonergic served thus increasing the concentration levels of serotonin (Ouchi et al., 2009). Another line of reasoning is that this Fluoxetine tends to prohibit or prevent serotonin reuptake but without affecting or interfering with corresponding norepinephrine uptake. The inhibitory effect of fluoxetine in reuptake can occur as long as 24 hours. Serotonin autoreceptors are found in the membrane cells, dendrites and axon, and function by preventing the firing and release of serotonin the associated neutrons. Studies have confirmed that substances that acts as inhibitors to serotonin reuptake usually increases serotonin extracellular levels thus activating 5-HT1A autoreceptors, and consequently lowing the production as well as the release of the neurotransmitter (Ouchi et al.,2009). Alcohol Though the impacts or resultant effect of Alcohol usually depend on the amount of dose may frequency, and sometimes depending on the chronic levels, Taking Alcohol may induce the production amnesia-associated feeling. Other effects may comprise of interrupted coordination, which can cause or interfere with speech, fine-motor skills, as well as delayed response. As a result, alcohol impact significantly on various normal cell functions and even modifies or changes the activities of many neurotransmitters. Intake of Alcohol affects serotonergic synaptic transmission in the brain in various ways depending on the level of dose consumed. An incident of alcohol intake in human triggers the degree of serotonin metabolites resulting in an increased serotonin (Lovinger, 1999: 24). In a separate study if was confirmed that insufficient or lack of serotonin in humans impacted significantly in both mood disturbance as well as disturbances in cognition. In addition, it is also linked to aggressive tendencies. According to Hoakena and Stewart, if at all According to alcohol is taken before a provocative or anxiety-eliciting event, its anxiolytic properties will generally reduce the possibility of an appropriate appraisal of that particular event. In this case, fear is eliminated and as a result of this, the inhibitory effects that fear often exerts on aggressive behaviour are thus inhibited (Hoakena and Stewart, 2003:1537). Marijuana and the cannabinoids The most common effect of Cannabis on human beings is the resultant heightening blood flow next to the skin, which generally cause feeling of warmth and increased heart beat. According to Iversen (2000 behavioral effects associated with the use of marijuana often takes four main stages. The first one is described as the "buzz," stage, which is a short stage of the first reaction. Some of the effects at this stage may include dizziness. The second stage is known as the "high" is associated with euphoria and exhilaration and disinhibition feelings. Iversen believes that if at all, an individual takes large dose of cannabis, and then the level of intoxication will proceed to the next phase where the person may exhibit some calmness, relaxed or even may go in a dreamlike state. Some of the Sensory reactions may include the feeling of floating, illusions, among others. All in all, these drugs, Marijuana and the cannabinoids, often work towards depressing various elements or normal functioning processes (Meyer and Quenzer, 2005). Opiates Another related drug is the opiate drug which is one of narcotic analgesics which can lessen pain but without eliciting unconsciousness. Unfortunately regular use of this drug leads to some kind of dependency or simply put, addition to pain killers. Opiate generally act on a variety of neuron found in the brain for instance endorphins and morphine like substances produced naturally in the human body (Noori et al,2008:185). It also associated with some feelings of relaxation and sleep, but when administered in high does may cause death. The connection between this drug and neurotransmitters can be explained by its opiates’ role in diminishing pain which in most cases relates to a complex interplay of neurological systems majorly in the spinal cord level. The pathways usually starts with reactions of neurotransmitters particularly noradrenalin and serotonin. Opiate interferes with neurotransmitters by simply mimicking their effects as illustrated in particular cell membrane receptors (Henderson, 2001). Cocaine is yet another drug that often interferes with many neurotransmitter systems. Like other drugs, Cocaine, is often believed have both positive and negative effects with the balance of these effects determining the extent of its abuse (Serafine et al 2011:1161). It is generally associated with a general sense of well-being among other feeling. In significant high levels of doses or prolonged administration, cocaine can result in various negative impacts including but not limited to feelings of anxiety, exhaustion, irritability, and even insomnia. Most behavioral tendencies of cocaine can be attributed to its ability to interfere or prevent the reuptake of the range of neurotransmitters particularly dopamine and norepinephrine, and serotonin thus inhibiting the functions of these neurotransmitters. Conclusion The study sought to explore the underlying mechanism that explains the effects of psychoactive dugs in human beings with special focus on psychobehaviour roles of neurotransmitters. From the study, it is clear that these drugs generally interfere with the normal functioning of the neurotransmission and consequently leading to behavioural changes. This therefore calls for caution when using drugs such like opiates and strictly avoidance of other harmful psychoactive drugs discussed in the foregoing paragraphs. References Ayala, M.E., (2009) Brain Serotonin, Psychoactive Drugs, and Effects on Reproduction Central Nervous System Agents in Medicinal Chemistry, 2009, 9, 258-276 Ciccarelli, Saundra K., and White, J.N., 2008 Psychology, Books a la Carte plus MyPsychLab (2nd Edition). 2 ed. Alexandria, VA: Prentice Hall. Colin Blakemore and Shelia Jennett (2001) opiates and opioid drugs. The Oxford Companion to the Body. (Online) Retrieved March 13, 2012 from Encyclopedia.com Hoaken, P.N., and Stewart, S.H., (2003) Drugs of abuse and the elicitation of human aggressive behavior Addictive Behaviors 28 (2003) 1533–1554 Iversen, L. (2000). The Science of Marijuana. New York, NY: Oxford University Press. ISBN 978-0195131239. Lovinger, D.M., (1999) The Role of Serotonin in Alcohol’s Effects on the Brain Current Separations 18:1 (1999); 23-28 Meyer, J.S.; Quenzer, L.F. (2005). Psychopharmacology: Drugs, the Brain, and Behavior. Sunderland, MA: Sinauer Associates. Noori,R., Rafiey, H., Solaiman-nia,L., Narenjiha, H., Assari, S., and Lankari, M.M., (2008) Impacts of Spoubse Opinate dependence on the Partner’s sexual functions, Journal of Familiy and reproductive helath, December,2008, Vol2(4):185-189 Ouchi, Y., Yoshikawa, E., Futatsubashi, M., Yagi, S., T Ueki, T., and Nakamura K., (2009) Altered Brain Serotonin Transporterand Associated Glucose Metabolism in Alzheimer Disease. The Journal of nuclear medicine, Vol. 50(8):1260-126 Read More