BRAIN AND PERSONALITY PRESENTATION ANUSREE PM MSC APPLIED PSYCHOLOGY
THE BRAIN AND PERSONALITY The relationship between the brain and personality is one of the most fascinating areas of neuroscience and psychology. The human brain, is a complex dynamic entity, plays a pivotal role in shaping our thoughts, emotions, behavior and personality. Brain is composed of many parts that work together to organize our movements, create thoughts, form emotions, and produce our behavior. Our personality, which consists of enduring patterns of thoughts, emotions, and behavior, is deeply rooted in the brain’s structure and functioning. Various regions of the brain are responsible for different aspects of our personality, and together, they form a complex system that governs how we perceive and interact with the world.
THE BRAIN AS A SEAT OF PERSONALITY:UNDERSTANDING THE KEY REGIONS There are some key regions in the brain that are highly related to personality.They are: THE LIMBIC SYSTEM The limbic system is a midline structures that circle the thalamus. The limbic means “ring” In human as well as animals, the limbic system guides rudimentary survival behavior. That is, it contains the basic modules for aggression, fear, sexuality, and the satisfaction of hunger or thirst. Most emotional experience can be traced at least in part to these brain centers. (Emotional brain)
The major structures of the limbic system includes the amygdala,the hippocampus,the hypothalamus,the mammillary bodies,the caudate nucleus,the fornix,and the cingulate cortex.
The Cingulate Cortex: It is a part of the brain that lies between the phylogenetically older limbic system structures and the neocortex. It links the hippocampus and the thalamus, playing a role in the storage of long-term memories, especially those dealing with strong emotions or traumatic life events. It appears to help focus attention, especially to events that may pose a risk to survival, and is therefore crucial for decision making. Thus, it plays an important role in storing memories as well as coordinating the emotional input from other brain structures in the assessment of the potential risks and rewards. In addition, it appears to play a role in the conscious apprehension of pain and emotion.
The Amygdala: Almond shape, resides bilaterally within each hemisphere; it is the primary source of feelings of fear and rage. As with most organs in the human body, it functions in certain ranges. Thus, people who are characteristically fearful rather than daring, or hostile rather than complacent, can be understood at least in part as having different levels of activity in their amygdala. Damage to amygdala can result in the ability to learn what to fear or even to understand the meaning of fear. Similarly, lesions in this part of the brain can lead to a lack of anger, and even the most aggressive and hostile person can be reduced to one who is relatively passive and calm. The role of amygdala in personality is particularly notable because this primeval and nonverbal brain center is instrumental making judgments, especially those dealing with the interpretation of emotions in other people’s facial expressions.
The Hippocampus: The hippocampus is the nexus of several important cognitive functions ,the most important of which is assimilation of short-term memory by long- term stores and the retrieval of memory from these stores. When we are exposed to sensory data, our brain try to make sense of it by asking in effect, ”Have I seen this before?” If the answer is yes, the brain triggers the appropriate memory locations and a reference to the input is found. If the stimulus is new ,it will be processed by the hippocampus for the long-term storage-especially if it is considered significant. In addition to its role in consolidating long-term memories, the hippocampus is the portion of the brain that appears to be responsible for our memory of spatial locations; that is our cognitive maps.
The Insula or Insular Cortex: This structure resembles a small brain residing deep within each hemisphere. It appears to be instrumental in many mental functions that underlie both the conscious experience of emotions and the personality. For example, there is evidence that the insula works with the mirror neurons to beget feelings of empathy. It plays a role in processing sensory information that can lead to emotion of disgust. Recent evidence reveals that the insula serves to integrate sensations from the body and use them as a basis for both decision making and motivation.
The Hypothalamus: Within the limbic system, a relatively tiny portion of the brain called the hypothalamus plays an important role in manage our body temperature, hunger and thirst, mood, sex drive, blood pressure and sleep. The hypothalamus also regulates the pituitary gland and it release of most major hormones. The major role of hypothalamus would be homeostasis . It serves to keep all the body’s organ system in balance. Damage to this structure, depending on the location of injury, can results in hyperphagia[overeating], anorexia, passivity, aggression, hypersexuality, or asexuality. Hypothalamus usually interact smoothly with the other brain structures, but sometimes, there are conflicts. One example of a conflict is obesity, a condition in which the person’s conscious goal of weight loss is often trumped by compelling feelings of hunger.
The Caudate Nucleus: The caudate nucleus is a part of the basal ganglia that plays several essential roles in the coordination of movements, emotional controls, and thoughts. It lies between the amygdala and the globus pallidus. The basic functions of the caudate nucleus is to link the physical coordination of the body with the person’s emotional state. The Mammillary Bodies: These structures are so named because of they resemble the shape of female breasts. The mammillary bodies plays a role in the consolidation of memory. People suffering from the Korsakoff’s dementia, an illness associated with severe anterograde amnesia, confabulation, and cognitive deficits, usually have evidence of damage to the mammillary bodies.
2. THE CEREBRAL CORTEX:THE EXECUTIVE REGION The most important part of the human brain is the cerebral cortex, the wrinkled surface of the brain. It lies above the limbic and other subcortical structures and is intimately connected with them. The cortex plays a crucial role in a great many behaviors, including perception, movements, and our higher intellectual functioning such as memory and reasoning. We are who we are as a result of the interplay between the cortex and all other structures of the brain. Without the emotional and sensory information from the centers below it, the cortex becomes complex. It would be unable to employ the mirror neurons that have been shown to apprehend and duplicate the actions of others. It would not be able to learn from that lead to emotion-laden events. Nor would it be able to draw on the vast repository of memories that are encoded in the limbic structures.
Case studies: Elliot, a man who suffered damage to the neural pathways connecting the limbic structures to the frontal lobes of his brain. This individual suffered a profound change to his personality. His cognitive capacity was largely unimpaired, but he was no longer recognizable to those who had known him as Elliot. His moral values had changed, his social judgment was that of a sociopath, and his ability to relate to others was radically impaired. 2. Phineas Gage’s Accident : In 1848,Phineas Gage had a workplace accident in which an iron rod entered and exited his skull. He survived but his personality changed as a result. Although his memory, cognition, and strength had not been altered, his once gentle personality slowly degraded. He became a man of bad and rude ways, disrespectful to colleagues, and unable to accept advice. This case study makes clear that our personalities exist somewhere, and that place is our brain. Although the human personality has not been localized to specific brain regions, it is clear that if critical brain areas are damaged or injured, the individual’s personality will change
INTERACTION WITH THE ENVIRONMENT The evidence that a major portion of human personality is genetic or biological in origin. Nevertheless, virtually all inherited traits are, at least in part, shaped by the environment in an interactive fashion. That is, human can shape their environment, which may lead to change in the environment that affects the developing personality. Although some researchers deny that genetic factors play a role in our development, some assert that genes alone cannot explain the diversity observed in both human and animal development. In humans, the most prominent example is that of monozygotic or identical twins. In terms of personality, they are generally similar but never identical. Thus, even with the identical genes, people differ, indicating that environment must play a role. People can alter their environment and that can result in changes to the people that performed shaping. People modify the environment that is instrumental in shaping the expression of our genes. Alteration of the environment is accomplished in numerous ways Humans build cities, which create a new environment. Based on our needs; for example, we level forest to create farmland, which in turn reduces the need for hunting and gathering.
BRAIN AND PERSONALITY TRAITS x BRAIN STRUCTURES FUNCTIONS PERSONALITY TRAITS Prefrontal cortex Decision making, self-control, social behavior, and personality expressions. high activity in prefrontal cortex – conscientiousness, responsibility, and emotional regulation. Lower activity-impulsivity and disinhibition Amygdala Processes emotions, especially fear and pleasure. Larger or more reactive amygdalas are linked to neuroticism(emotional instability) and sensitivity to negative emotions. Hippocampus Memory formation and learning. Linked to openness to experience, creativity, and adaptability to new situations. Hypothalamus Regulate physiological processes like hunger, sleep, and stress response. Its role in stress response connects it to traits such as anxiety and aggression.
Anterior cingulate cortex Involved in emotion regulation, decision-making, and impulse control Higher activity-empathy, agreeableness, and conscientiousness. Dysfunction may relate to emotional dysregulation. Insular cortex Processes bodily sensations and emotional awareness. Related to self-awareness and emotional sensitivity, often associated with neuroticism and introversion Basal ganglia Involved in movement regulation, habit formation, and reward processing. Dysfunction in basal ganglia can lead to impulsivity or obsessive tendencies, which are linked to traits such as extraversion and conscientiousness.
In evolutionary terms, which is the oldest part of the human brain? a)The limbic system b)The cortex c)The right hemisphere d)The brain stem 2. The ________is to feeling fear as the _______is to feeling pleasure. a)Pons/Medulla b)Amygdala/Hypothalamus c)Thalamus/Hypothalamus d)Cerebellum/Amygdala
3. Sunita, a 12 year old girl, shows exceptional musical ability. Both her parents are accomplished singers, and they send her for classes for voice training after school. Her capabilities are most likely to be the result of : a)Heredity only b)Growth and maturation c)Heredity and environment d)Genetic makeup 4. The process of the brain adapting to changes and recognizing its neural pathways is called: a)Neurotransmission b)Synaptic drift c)Neuroplasticity d)Neuronal oscillation
5. The belief that children’s behavior can be modified by reinforcers and punishers is based on the idea that development is primarily influenced by- a)Heredity only b)Both heredity and environment c)Environment only d)None of the above The parts of the human brain that helps in regulation of sexual behavior, expression of excitement, pleasure, rage, fear etc. are: a)Limbic system and hypothalamus b)Corpora quadrigemina and hippocampus c)Brain stem and epithalamus d)Corpus callosum and thalamus
7. Agreeableness is a personality trait that includes which of the following attributes? a)Moodiness b)Altruism c)Arrogance d)Deception 8. The part of the brain that works with mirror neurons to beget feelings of empathy is a)Hippocampus b)Insula c)Hypothalamus d)Amygdala
9. Which of the following statement is NOT true about temperament? a)Temperament is an early indication of personality. b)Temperament is observable in babies within their first few weeks. c)Temperament is an individual’s level of emotional excitability. d)Temperament and personality are the same thing. 10. __________part of the brain is associated with reasoning, decision making and problem solving a)Hippocampus b)Prefrontal cortex c)Amygdala d)Medulla oblongata
ANSWERS D B C C C A B B D B
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