Discuss The Behavioral Genetics Of Individual Differences

Discuss The Behavioral Genetics Of Individual Differences Being Su

Discuss the behavioral genetics of individual differences, being sure to focus on common misunderstandings about heritability estimates. Two brain structures have been most frequently linked to human emotion. Which are they? Describe research that has implicated each in human emotion. Explain color constancy. What important points does it make about the mechanisms of color vision? Describe a theory of color vision that can explain color constancy, focusing on the evidence that led to the theory. Compare set-point and positive-incentive theories of hunger and eating. Compare their ability to predict two major research findings. Describe and discuss sexual dimorphisms of the mammalian brain. How do they develop? Include cyclic gonadotropin release, the sexually dimorphic nucleus, and the aromatization hypothesis in your answer. What distinguishes biopsychology from the other subdisciplines of neuroscience? A. its focus on the study of behavior B. its focus on animal subjects C. its focus on psychiatric disorders D. its focus on psychoactive drugs. Structure of the nervous system is to function of the nervous system as A. biopsychology is to psychology. B. neuroanatomy is to neurophysiology. C. neuropathology is to clinical psychology. D. neuroscience is to biopsychology. In the study of heritability estimates, increasing the genetic diversity of the subjects without introducing other changes would likely A. decrease the heritability estimate. B. confound the experiment. C. increase the accuracy of the heritability estimate. D. increase the heritability estimate. The sensitive period for the development of a particular trait is the period A. of chronic pain. B. of sexual receptivity. C. of fertility. D. during which a particular experience must occur to have a major effect on the development of the trait. Deterioration of the pathway from the substantia nigra to the striatum is often found in cases of A. Korsakoff's syndrome. B. Parkinson's disease. C. autism. D. Alzheimer’s disease. Which of the following are multipolar cortical neurons with long axons, apical dendrites, and triangular cell bodies? A. stellate cells B. chandelier cells C. pyramidal cells D. granule cells. Many self-stimulation sites A. contain serotonergic neurons. B. are part of the mesotelencephalic dopamine system. C. are adrenergic. D. are glutaminergic. Which of the following drugs produces Buerger's disease? A. tobacco B. morphine C. marijuana D. cocaine. Darwin believed that A. expressions of emotion evolve from behaviors that indicate what an animal is likely to do next. B. expressions of emotion evolve in ways that enhance their communicative function and that their original function may be lost. C. opposite messages are often signaled by opposite movements and postures. D. all of the above. The pattern of behavior that is observed in monkeys after their anterior temporal lobes have been removed is called A. sham rage. B. the Kluver-Bucy syndrome. C. hippocampal rage. D. septal rage. Many studies have found structural and functional brain pathology in patients suffering from affective disorders. Although there is little consensus about the exact location of the brain pathology, it is most commonly observed in three structures. These structures include the A. amygdala and medial prefrontal cortex. B. hippocampus and medial prefrontal cortex. C. amygdala and hippocampus. D. all of the above. Clinical depression and anxiety are comorbid disorders, which means that they A. both increase the likelihood of suicide. B. both increase susceptibility to terminal illness. C. have the same effect on neurochemicals. D. tend to occur together in the same individuals. A. T. is a woman with selective damage to her dorsal visual stream. She has A. little difficulty making accurate movements under visual control. B. substantial difficulty making accurate movements under visual control. C. substantial difficulty consciously recognizing objects. D. lost all ability to respond to moving images. In general, information in the primary visual cortex is thought to flow from __________ to __________ to __________. A. lower layer IV; simple cells; complex cells B. lower layer IV; complex cells; simple cells C. simple cells; lower layer IV; complex cells D. simple cells; complex cells; lower layer IV. In the classic transection experiments of Lawrence and Kuypers, monkeys with all their dorsolateral motor pathways transected sat with their arms hanging limply by their sides. However, these same monkeys had no difficulty A. picking up pieces of food and then releasing them. B. using their arms for standing, walking, and climbing. C. reaching for moving objects. D. moving their fingers independently. According to current theory, the sensorimotor system A. is largely ballistic. B. is largely, if not entirely, ipsilateral. C. comprises a hierarchy of central sensorimotor programs. D. all of the above. The three phases of energy metabolism are, in sequence, A. eat, fast, and absorb. B. absorptive, cephalic, and fasting. C. cephalic, absorptive, and fasting. D. fasting, absorptive, and cephalic. Set-point theories of hunger and eating are inconsistent with A. eating-related evolutionary pressures as we understand them. B. the major effects on eating of taste, learning, and social factors. C. the failure of researchers to confirm that energy deficits are the usual stimuli for eating. D. all of the above. Which of the following statements is true? A. Men and women have fundamentally different anterior pituitaries. B. Men and women have fundamentally different posterior pituitaries. C. A male pituitary transplanted into a female displays a cyclic pattern of hormone release. D. A female pituitary transplanted into a male displays a cyclic pattern of hormone release. The external reproductive organs of males and females develop A. from different tissue. B. from the same bipotential tissue. C. under environmental control. D. under direct genetic control.

Paper For Above instruction

The exploration of behavioral genetics provides profound insights into how individual differences in behavior are influenced by genetic factors, a subject often misunderstood due to misconceptions about heritability estimates. Heritability refers to the proportion of variance in a trait that can be attributed to genetic variance within a population. However, a common misunderstanding is that high heritability implies immutability or that the trait is determined solely by genes, disregarding environmental influences. For example, research indicates that heritability estimates for intelligence vary across populations and environments, emphasizing that heritability is not a fixed measure but context-dependent. Misconcluding that heritability applies to individuals rather than populations often leads to flawed interpretations about the role of genetics in behavior (Plomin et al., 2013).

Two structures notably linked to human emotion are the amygdala and the medial prefrontal cortex. The amygdala is responsible for processing emotions like fear and pleasure, demonstrated through studies showing its activation during emotional episodes and its role in fear conditioning (LeDoux, 2000). Neuroimaging research indicates that the amygdala's activity correlates with emotional intensity in humans. The medial prefrontal cortex, on the other hand, is implicated in regulating emotional responses and exerting top-down control over the amygdala (Banks et al., 2007). Functional neuroimaging reveals that decreased activity in the medial prefrontal cortex is observed in individuals with anxiety disorders, indicating its role in emotional regulation.

Color constancy illustrates the brain’s ability to perceive consistent object colors despite variations in illumination. It underscores that color perception is not solely a product of retinal photoreceptors but involves complex neural processing that compensates for lighting changes. A significant theory explaining this phenomenon is the retinex theory proposed by Edwin Land, which suggests that the brain compares information across the visual scene to infer the true color of objects. Evidence supporting this theory includes experiments demonstrating that uniform illumination changes do not alter perceived object color, indicating active neural processes that maintain color constancy (Land, 1977).

Set-point theories posit that the body maintains a stable internal state, such as weight, through homeostatic mechanisms. In contrast, positive-incentive theories argue that hunger is driven not just by energy deficits but by the anticipated pleasure of eating. Set-point models predict that deprivation leads to increased hunger and intake, but they fail to account for influences like taste preferences and social factors, which positive-incentive theories incorporate. Research evidence shows that animals and humans often seek foods beyond caloric needs, motivated by flavors and social cues, supporting positive-incentive mechanisms (Galeras et al., 2012).

Sexual dimorphism of the mammalian brain involves structural differences that develop under the influence of hormones, especially during critical periods of development. The sexually dimorphic nucleus (SDN) of the preoptic area in rodents is larger in males, a difference affected by testosterone exposure during development, which is converted to estrogen through aromatization. The aromatization hypothesis explains that testosterone is aromatized in the brain to estrogen, which then influences the development of male-typical brain structures. Cyclic gonadotropin release further modulates these processes by regulating sex hormone levels, shaping structural differences underlying male and female behaviors (Gorski et al., 1980).

Biopsychology distinguishes itself from other neuroscience subfields primarily through its focus on the biological bases of behavior. Unlike clinical neuropsychology, which emphasizes diagnosis and treatment of disorders, or neuroanatomy, which concentrates on brain structure, biopsychology emphasizes the relationship between neural functioning and behavior, integrating physiology, psychology, and neuroscience to understand how the brain influences the mind (Pinel, 2012).

The structure-function relationship in the nervous system extends across levels of organization. Neuroanatomy examines the organization of brain structures, while neurophysiology studies how neurons function. These fields complement each other, with neuroanatomy providing the structural framework and neurophysiology elucidating functional processes. Together, they form the foundation of neuroscience, illustrating the link between brain anatomy and its functional output (Kandel et al., 2013).

In heritability studies, increasing genetic diversity among subjects without changing other variables can decrease heritability estimates because greater genetic variation introduces more environmental and genetic heterogeneity, complicating the attribution of variance solely to genetics. Thus, the estimate of heritability becomes more conservative and reflective of the true genetic contribution amidst diverse genetic backgrounds (Rutter, 2006).

The sensitive period for development refers to a timeframe during which experiences have a significant impact on the development of a trait. For example, the critical period for sexual receptivity in some animals necessitates specific stimuli during early development; deprivation during this window can result in permanent deficits, highlighting the importance of timing in developmental processes (Knudsen, 2004).

Deterioration of the pathway from the substantia nigra to the striatum is characteristic of Parkinson’s disease, causing a hallmark depletion of dopamine, which results in motor control issues such as tremors and rigidity. This pathway deterioration affects movement regulation, illustrating the importance of dopaminergic systems in motor function (Dauer & Przedborski, 2003).

Cortical neurons with long axons, apical dendrites, and triangular cell bodies are classified as pyramidal cells, which are the primary excitatory neurons in the cerebral cortex and play vital roles in neural communication and processing (Herculano-Houzel et al., 2015).

Self-stimulation sites, highly involved in the brain’s reward pathways, typically contain serotonergic neurons and are a part of the mesotelencephalic dopamine system, which mediates reinforcement and motivation processes (Olds & Milner, 1953).

Buerger’s disease (thromboangiitis obliterans) is strongly associated with tobacco use, with smoking believed to cause inflammation and occlusion of small and medium arteries, leading to ischemia in limbs (Ross & Shadwick, 1974).

Darwin believed that expressions of emotion evolve through natural selection, serving communicative functions, with some behaviors or postures originally adaptive but potentially losing their original purpose over time. His theories emphasized the evolutionary origins and communicative significance of emotional expressions (Darwin, 1872).

Kluver and Bucy observed that monkeys with temporal lobe removal exhibited placid, hyperoral, and hypersexual behaviors, which they termed the Kluver-Bucy syndrome, illustrating the role of temporal structures in emotional regulation and behavior (Kluver & Bucy, 1937).

Brain pathology in affective disorders most frequently involves the amygdala, hippocampus, and medial prefrontal cortex. Many findings point to abnormal functioning in these regions, affecting emotional processing and regulation, contributing to depression and anxiety (Drevets et al., 2008).

Depression and anxiety disorders are often comorbid, occurring together within individuals, and sharing neurochemical and neuroanatomical features, which suggests overlapping neural substrates and pathophysiological mechanisms (Kendler et al., 2003).

A woman with damage to her dorsal visual stream (the "where" pathway) experiences difficulty making accurate movements under visual control, indicating the dorsal stream’s role in spatial localization and visually guided actions (Goodale & Milner, 1992).

Information in the primary visual cortex generally flows from lower layer IV to simple cells, then to complex cells, and later processes involve feedback loops and integration, making this pathway essential for constructing visual perception (Felleman & Van Essen, 1991).

In Lawrence and Kuypers' experiments, monkeys with corticospinal pathway lesions could still perform basic movements like reaching and grasping, indicating that some motor functions are mediated by other pathways, such as brainstem circuits (Lawrence & Kuypers, 1968).

The sensorimotor system is hierarchical, consisting of multiple levels of central programs that generate movement sequences, often described as largely ballistic or preplanned, which can be refined via feedback. Integration of these programs enables complex motor behavior (Mattingly et al., 2017).

Energy metabolism involves three phases: the cephalic phase (anticipatory responses), absorptive phase (nutrient uptake and storage), and fasting phase (use of stored reserves). These phases reflect the body’s regulation of energy to maintain homeostasis (Carmichael & Smith, 2015).

Set-point theories suggest a stable target weight or energy level maintained via homeostasis, but they are limited because they do not account for the influence of taste, social factors, and learned preferences. Evidence shows that intake is often driven by external cues beyond energy needs, challenging simple set-point models (Keays et al., 2003).

Regarding the development of reproductive organs, the external genitalia originate from the same bipotential tissue, with hormonal influences, such as testosterone and its aromatization to estrogen, directing their differentiation. This process exemplifies the interplay between genetic and hormonal factors in sexual development (Gooren & Bormann, 2016).

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