Saturday, August 24, 2013
Brain Function and Psychology
Brain Function and Psychology
Psychological research covers a broad range of topics and interests, although the study of the human brain is compelling for research psychologists. Because of the intricate and complex association between behavior and the brain, some areas of brain function hold more interest than others. The goal of this paper is to describe the divisions of the brain that are most interesting to research psychologists. In addition, it will describe the divisions of the brain that I might be interested in researching, as well as the reasoning behind these personal preferences.
Scientific Interest in the Brain
The divisions that create interest for research psychologists are the two hemispheres of the cerebrum, wherein higher level functions are directed, where memories are stored and retrieved, feelings and emotions are interpreted, and complex human judgments are made. In addition, neural systems in the limbic system, which are said to regulate emotional behaviors are also of great interest to research psychologists (Breedlove, Watson, & Rosenzweig, 2010). Because of the importance of the biological basis of behavior to these researchers, extensive research is undertaken on the chemical and electrical communication systems in the brain. Although understanding the electrical nature of the neural systems garners considerable interest, it is equally compelling to explore the chemical nature of communication between the nerve cells, and the role of neurotransmitters in the regulation of behavior.
Research psychologists focus on why people behave and think the way they do. People think and remember, desire and feel, and perhaps, most compelling, they perceive one event in a number of ways (Mahoney, 2001). Although a superficial exploration of the brain may lead to the discovery of structures and functions, deep within these structures lies the brain's capacity to transmit chemical and electrical information that translates to human behavior (Neumann, 2010). Neumann (2010) sums human behavior as a potential generated and realized by billions of neurons in the brain and their ability to communicate information in the brain's ecosystem.
The Electrical and Chemical Signaling of Neurons
When approaching human behavior from a biological and psychological perspective, two basic assumptions are that biological states cause psychological consequences and psychological events can cause biological consequences. Because of the inextricable connection between the brain and behavior and the brain's relationship to psychological dysfunction and disease, biological psychology is concerned with the biology of the brain and neural functioning. For example, Urakawa et al., (2013) found a stimulating environment augmented specific neuron types in the amygdala, which affected the level of anxiety in rats. From another perspective, the activation of specific neurons in the pre-frontal cortex showed an increase in appetitive behavior (Burgos-Robles, Bravo-Rivera, & Quirk, 2013). Both examples describe the direct association between the brain and behavior, and more specifically, neurons in the brain and behavior.
From a slightly different perspective, in the synapses at one end of the neuron, chemical transmitters transport information across the synaptic cleft. The level of functioning of the resulting neurotransmission directly affects behavior. For example, a deficient amount of the neurotransmitter dopamine can cause Parkinson's disease and schizophrenia, and it plays a significant role in the health of the immune system (Buttarelli, Fanciulli, Pellicano, & Pontieri, 2011). The successful transmission of other chemical signals has powerful implications for psychological health and well-being. These include serotonin, acetylcholine, norepinephrine, and other substances that severely affect psychological functioning and behavior (Breedlove et al., 2010). Research has described the action or inaction of neurotransmitters as culpable in addiction (Koob & Volkow, 2010; Volkow et al., 2010). Further, the abnormal transmission of neurochemicals between neurons has been implicated in schizophrenia, depression, generalized anxiety disorder, and some personality disorders (Hansell & Damour, 2008).
Research on neural communication in the brain provides a way to understand diseases such as epilepsy, multiple sclerosis, and Alzheimer's, as well as the damage caused by cerebral palsy, Parkinson's and other neurodegenerative diseases (Breedlove et al., 2010). As neuroscientists continue to uncover the often mysterious nature of the brain and its affect on behavior, psychologists, through research, find new opportunities to provide relief from the conditions that continue to evade contemporary modes of treatment (Hansell & Damour, 2008). Insight gained from biopsychological research provides a more accurate understanding of human behavior, that its roots reside in the biology of the brain and nervous system (Breedlove et al., 2010).
Personal Interest in the Brain
The areas of the brain that are personally interesting are the frontal lobes. After first being exposed to the plight of Phineas Gage and the damage to his frontal lobe, I became interested in the part of the human brain that accounts (at least in part) for defining human personality traits and the cognitive functions characteristic only to humans (Bird, Castelli, Malik, Frith, & Husain, 2004). According to Stuss, Gow, and Hetherington (1992), damage to this part of the brain can cause drastic changes in an individual's capacity to function appropriately and in a socially acceptable manner. According to most accounts of Phineas Gage's frontal lobe damage, it left him radically different to the extent his friends claimed he was no longer the person he once was (Stuss, Gow, & Hetherington, 1992).
The frontal lobes envelop an extensive network of neurons sensitive to dopamine, which has been associated with motivation, emotional memory, and feelings of reward (Bird et al., 2004). The frontal lobes play an important role in translating emotionally-charged memories generated by the limbic system, and in modifying and managing these memories in a way that complies with normal expectations and social norms (Bird et al., 2004). The frontal lobes are said to be associated with the concept of mentalizing, which is the ability of the human brain to anticipate specific behaviors and to attribute mental processes and frame of mind to others (Bird et al., 2004). This human capacity may be vital for individuals to understand and engage in successful social interaction (Bird, et al., 2004). The frontal lobes are responsible for regulating emotions, and damage to the area can cause irritability and explosive behavior. Additionally, damage to the frontal lobes can cause increased vulnerability to substance abuse and impulsive and volatile behavior (Stuss et al., 1992).
Frontal lobe damage can alter one's social self, leaving individuals in social isolation without the ability to engage in human relationships (Stuss et al., 1992). Self-awareness and reflection are severely distorted or become non-existent after frontal lobe damage. Perhaps one of the most compelling functions of the right frontal lobe, is its role in the human appreciation of humor, which is a "defining human attribute" (Shammi & Stuss, 1999, p. 659). The frontal lobe may be responsible for the integration of cognitive thought processes and affective information, which enables the exclusively human capacity for self-awareness and reflection (Shammi & Stuss, 1999).
Many of the distinct traits of humankind, such as humor appreciation and the ability to understand and empathize with the experiences and emotions of others, the tendency to work toward social acceptance and maintaining social relationships are generated within the frontal lobe of the brain (Shammi & Stuss, 1999). These intrinsically human tendencies as well as other qualities that produce individual personality traits are lost when this brain structure is damaged (Blumer & Benson, 1975). The frontal lobe seems almost like a responsive radar system, providing humans with the capacity to receive feedback from their surroundings and respond in an exclusively human, socially appropriate manner (Stuss et al., 1992).
Frontal lobe damage may leave intact the basic abilities and intelligence of the individual, but without the characteristics that define human individuality. The hallmarks and basic tenets of human nature seem to be under the control of the somewhat arcane structures and functions of the frontal lobes. The complex nature of higher level thinking, such as the appreciation of humor, and the ability to self-reflect and to think according to social reason are characteristics exclusive to humankind. Human evolution may owe its development to the evolution of the higher level functioning of the frontal lobes, which may generate the characteristics inherent in complex cognitive processes (Stuss et al., 1992).
Coming full circle, in the appreciation of brain structures and their functions, within each brain structure or division, neural signaling, or the lack of it, enables or disables the functions normally specific to the frontal lobes, or any other area of the brain (Breedlove, Watson, & Rosenzweig, 2010). Although research psychologists may study a variety of brain structures or functions, it is the study of neural activity and its chemical and electrical communication that provides the most detailed account of the biological basis of behavior.
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