PSYC1113_F24_Week3_4_TheNervousSystem.pdf

Biology and Psychology PSYC-1113: Psychology for HSF Fall 2024 | Week 3  Agenda Reminders Quiz 1 Lesson Assignment Assignment 1 Feedback Nature vs Nurture  Nature vs Nurture Nature...

Biology and Psychology PSYC-1113: Psychology for HSF Fall 2024 | Week 3  Agenda Reminders Quiz 1 Lesson Assignment Assignment 1 Feedback Nature vs Nurture  Nature vs Nurture Nature Nurture the inborn, innate character of an environmental influences that organism shape behaviours Images CC0 from Pixabay Review: The Biopsychosocial Model Image Source: Wikimedia Commons Creative Commons Attribution-Share Alike 4.0 International Copyright © 2023 Cengage Learning Canada, Inc.  Evolution and Heredity Charles Darwin (1871): proposed a theory of evolution. Natural selection: adaptive genetic variations among members of a species enable individuals with those variations to survive and reproduce. Humans, like other species, evolved and adapted. Copyright © 2023 Cengage Learning Canada, Inc.  Evolutionary Psychology Evolutionary psychology is the branch of psychology that studies the ways in which adaptation and natural selection are connected with mental processes and behaviour. Psychological traits might undergo a similar process of natural selection as Darwin described for physical traits. Adaptive psychological traits could be passed on genetically from generation to generation. It emphasizes instinctive behaviour in species. E.g., infant reflexes Copyright © 2023 Cengage Learning Canada, Inc.  Heredity and Genetics Heredity: biological transmission of character and biological traits from parents to children via genes https://images.nagwa.com/figures/explainers/402189501015/2.svg Copyright © 2023 Cengage Learning Canada, Inc.  Genes and Genetics Genes are the basic unit (building block) of heredity found at a specific point on chromosomes Genetics: subfield of biology that studies heredity Behavioural genetics: the study of genetic transmission of traits that govern behaviour patterns or psychological traits  Key Terms Gene basic unit (building block) of heredity found at a specific point on chromosomes Chromosomes structures within cell nucleus that carry genes humans have 46 chromosomes (23 pairs) DNA (deoxyribonucleic acid) substance that forms chromosomes takes form of double helix contains the genetic code 2-14 Copyright © 2023 Cengage Learning Canada, Inc.  Genotypes and Phenotypes Polygenic - refers to traits that are influenced by combinations of genes. Most psychological traits (e.g., mental health, general intelligence) are influenced by many genes. Genotype is a person’s genetic makeup, as determined by the sequencing of chemicals in their DNA. A genetic trait may be present in the DNA, but may or may not be expressed. Phenotype is the manifestation of a person’s genetic code; one’s actual development and appearance based on one’s genotype and environment Copyright © 2023 Cengage Learning Canada, Inc. https://geneticeducation.co.in/wp-content/uploads/2020/05/Genotype-vs-phenoty.003.jpeg  Epigenetics Epigenetics is the study of changes in gene function because of environmental influences. E.g., Heijmans et al (2008) Dutch Hunger Winter E.g., Yehuda and Lehrner (2018) intergenerational trauma E.g., Nannini et al. (2023) cannabis use Copyright © 2023 Cengage Learning Canada, Inc.  Kinship Studies Kinship studies compare biologically related and biologically unrelated people; they study genetic influence on behavioural or psychological traits. Copyright © 2023 Cengage Learning Canada, Inc.  Twin Studies Twin studies compare the presence of traits and behaviour patterns in twins. Monozygotic (MZ) twins: twins that develop from a single fertilized ovum divides in two early in prenatal development thus share the same genetic code; also called identical twins Dizygotic (DZ) twins: twins that develop from two fertilized ova as closely related as brothers and sisters in general; also called fraternal twins Copyright © 2023 Cengage Learning Canada, Inc. Watch: Twin Studies The Nervous System  The Nervous System The nervous system is a system of nerves that control thought processes, heartbeat, visual–motor coordination, and many other abilities. It contains the brain, spinal cord, and other parts, enabling us – to receive information from the world outside – to act on that world Copyright © 2023 Cengage Learning Canada, Inc.  The Parts of the Nervous System The nervous system consists of: Nerves: bundles of axons from many neurons Central nervous system (CNS): brain and spinal cord Peripheral nervous system (PNS): somatic and autonomic nervous systems 2-23 Copyright © 2023 by Cengage Canada Divisions of the Nervous System Copyright © 2023 Cengage Learning Canada, Inc.  The Central Nervous System The central nervous system consists of the brain and spinal cord. The brain and spinal cord contain grey matter: unmyelinated neurons; some involved in spinal reflexes white matter: myelinated neurons that carry messages to and from the brain 2 = Grey matter; 3 = White https://w-radiology.com/white-gray-matter/  The Central Nervous System cont’d Spinal cord: a column of neurons within the spine –transmits messages from sensory receptors throughout the body to the brain, and back –is an “information superhighway” –responds to spinal reflexes, which are simple, unlearned responses to stimulation Brain: connected to the peripheral nervous system via the spinal cord Copyright © 2023 Cengage Learning Canada, Inc. The Peripheral Nervous System The peripheral nervous system (PNS) consists of sensory and motor neurons that transmit messages to and from the CNS. The PNS has two main divisions the somatic and autonomic nervous systems. The somatic nervous system consists of sensory and motor neurons that transmit messages to and from CNS and controls purposeful body movements. The autonomic nervous system (ANS) regulates the glands and muscles of internal organs and contains sympathetic and parasympathetic divisions. Copyright © 2023 Cengage Learning Canada, Inc. Branches of the Autonomic Nervous System: The Parasympathetic and the Sympathetic Copyright © 2023 Cengage Learning Canada, Inc. The Endocrine System  The Endocrine System Endocrine system: the body’s system of ductless glands that release hormones directly into the bloodstream Glands: organs that secrete one or more chemical substances such as hormones, saliva, or milk Hormone: a substance secreted by an endocrine gland regulates various body functions, including homeostasis, growth, metabolism, and some behaviours, hence of interest to psychologists 2-32 Copyright © 2023 by Cengage Canada  2-33 Copyright © 2023 by Cengage Canada  The Pituitary, Hypothalamus, and Pineal Gland The pituitary gland and the hypothalamus work in close cooperation. The pituitary gland is labelled as a “master gland.” It lies below the hypothalamus, its “commander.” It secretes growth hormone, prolactin, antidiuretic hormone, and other hormones. pineal gland: secretes hormone melatonin that regulates sleep-wake cycle 2-34 Copyright © 2023 by Cengage Canada  The Thyroid Gland The thyroid gland produces thyroxin, which affects the body’s metabolism. Deficiencies in thyroxin are associated with hypothyroidism and cretinism. Excesses of thyroxin result in hyperthyroidism. 2-35 Copyright © 2023 by Cengage Canada  The Adrenal Glands Adrenal glands are located above the kidneys. They secrete corticosteroids, which increase resistance to stress, promote muscle development, and increase the body’s energy supply. The sympathetic branch of the ANS causes secretion of epinephrine and norepinephrine, which help the body to respond effectively in threatening situations Epinephrine intensifies emotions, especially fear and anxiety. 2-36 Copyright © 2023 by Cengage Canada  The Testes and the Ovaries Testosterone is produced primarily by testes and triggers the development of male sex characteristics Estrogen is produced by ovaries and fosters female reproductive capacity and sex characteristics 2-37 Copyright © 2023 by Cengage Canada  HPA Axis Figure 1. Stress Response in the Human Body. In response to stress, cerebral cortex signaling stimulates the hypothalamus to release corticotropin-releasing hormone (CRH). In turn, CRH stimulates the pituitary gland to produce and release adrenocorticotropic hormone (ACTH) into the blood. ACTH then activates pathways in the adrenal glands for the synthesis and release of the stress hormone cortisol. As a consequence of chronic stress, such as repeated test anxiety, over- stimulation by cortisol can lead to the indicated deleterious side effects in the brain and central nervous system. https://www.mdpi.com/2673-7140/2/1/11 Assignment