Biological Basis of Behavior PDF

BIOLOGICAL BASIS OF BEHAVIOR Biological Psychology Neuron is the fundamental unit which makes up a Biological psychology, also called physiological psychology, is nerve pathway, neural...

BIOLOGICAL BASIS OF BEHAVIOR Biological Psychology Neuron is the fundamental unit which makes up a Biological psychology, also called physiological psychology, is nerve pathway, neural firing (neurotransmitter the study of the biology of behavior; it focuses on the nervous release) takes place at the level of the neuron, system, hormones and genetics. Biological psychology and many aspects of the physiology-behavior examines the relationship between mind and body, neural relationship mechanisms, and the influence of heredity on behavior.(McLeod, 2015) Glial Cells support the neurons in many ways such as by insulating them, synchronizing activity among Nervous System neighboring neurons, and removing waste is the basis for our ability products. to perceive, adapt to, and interact with the world around us (Gazzaniga, 1995, 2000; Gazzaniga, Ivry, & Mangun, 1998). Transduction the process of converting the physical/chemical energy to electrochemical messages Nerve Impulse refers to the series of separate action potentials that take place segment by segment as they move down the length of an axon. if an action potential starts at the beginning of an axon, All or none law the action potential will continue at the same speed, segment by segment, to the very end of the axon. is a tiny electric current that is generated when the Action Potential positive sodium ions rush inside the axon. The enormous increase of sodium ions inside the axon causes the inside of the axon to reverse its charge. The inside becomes positive, while the outside becomes negative which called DEPOLARIZATION REFLEX is an unlearned, involuntary reaction to some stimulus. The neural connections or network 1. Sensors underlying a reflex is prewired by These are specialized sensory receptors found in genetic instructions. senses organs 2. Afferent Neurons Afferent (AFF-er-ent), or sensory, neurons carry information from the senses to the spinal cord. 3. Interneurons An interneuron is a relatively short neuron whose primary task is making connections between other neurons 4. Efferent Neurons Efferent (EFF-er-ent), or motor, neurons carry information away from the spinal cord to produce responses in various muscles and organs throughout the body. THE DIVISION OF THE NERVOUS SYSTEM The central nervous system is made up of the The peripheral nervous system includes all the brain and spinal cord. From the bottom of the nerves that extend from the spinal cord and brain emerges the spinal cord, which is made up carry messages to and from various muscles, of neurons and bundles of axons and dendrites glands, and sense organs located throughout the that carry information back and forth between body. the brain and the body. The autonomic nervous system regulates heart The somatic nervous system consists of a rate, breathing, blood pressure, digestion, network of nerves that connect either to hormone secretion, and other functions. The sensory receptors or to muscles that you can autonomic nervous system usually functions move voluntarily, such as muscles in your limbs, without conscious effort, which means that only back, neck, and chest. a few of its responses, such as breathing, can also be controlled voluntarily. The sympathetic division, which is triggered by The parasympathetic division returns the body threatening or challenging physical or to a calmer, relaxed state and is involved in psychological stimuli, increases physiological digestion. arousal and prepares the body for action ORGANIZATION OF THE BRAIN BRAIN REGION FOREBRAIN The forebrain, which is the largest part of MIDBRAIN the brain, has right and left sides that are called hemispheres. The hemispheres, The midbrain has a reward or connected by a wide band of fibers, are pleasure center, which is responsible for an incredible number of stimulated by food, sex, functions, including learning and memory, money, music, attractive speaking and language, having emotional faces; has areas for visual responses, experiencing sensations, and auditory reflexes, such as initiating voluntary movements, planning, automatically turning your and making decisions. head toward a noise; and contains the reticular HINDBRAIN formation, which arouses the forebrain so that it is ready to The cerebellum, which is located at the very process information from the back and underneath the brain, is involved senses (Holroyd & Coles, in coordinating motor movements but not in 2002). initiating voluntary movements The medulla, which is located at the top of the spinal The pons functions as a bridge to transmit cord, includes a group of cells that control vital messages between the spinal cord and brain. reflexes, such as respiration, heart rate, and blood The pons also makes the chemicals involved in pressure. sleep (Monti et al., 2008). The frontal lobe, which is located in the front part of the brain, includes a huge area of cortex. The frontal lobe is involved in many functions: performing voluntary motor movements, interpreting and performing emotional behaviors, behaving normally in social situations, maintaining a healthy personality, paying attention to things in the environment, making decisions, and executing plans. The motor cortex is a narrow strip of cortex that is located on the back edge of the frontal lobe and extends down its side. The motor cortex is involved in the initiation of all voluntary movements. The right motor cortex controls muscles on the left side of the body, and vice versa. A frontal lobotomy was a surgical procedure in which about one-third of the front part of the frontal lobe (figure below) was cut away from the rest of the brain. The parietal lobe is located directly behind the frontal lobe. The parietal lobe’s functions include processing sensory information from body parts, which includes touching, locating positions of limbs, and feeling temperature and pain, and carrying out several cognitive functions, such as attending to and perceiving objects. The somatosensory cortex is a narrow strip of cortex that is located on the front edge of the parietal lobe and extends down its side. The somatosensory cortex processes sensory information about touch, location of limbs, pain, and temperature. The right somatosensory cortex receives information from the left side of the body, and vice versa. The temporal lobe is located directly below the parietal lobe and is involved in hearing, speaking coherently, and understanding verbal and written material. The primary auditory cortex (shown in red), which is located on the top edge of each temporal lobe, receives electrical signals from receptors in the ears and transforms these signals into meaningless sound sensations, such as vowels and consonants. The auditory association area (shown in blue), which is located directly below the primary auditory cortex, transforms basic sensory information, such as noises or sounds, into recognizable auditory information, such as words or music. Broca’s area, which is Wernicke’s area, which is usually usually located in the left located in the left temporal lobe, is frontal lobe, is necessary for necessary for speaking in coherent combining sounds into sentences and for understanding words and arranging words speech. into meaningful sentences. Damage to this area results in Damage to this area results Wernicke’s aphasia, which is a in Broca’s aphasia (ah- difficulty in understanding spoken or PHASE-zz-ah), which means written words and in putting words into a person cannot speak in meaningful sentences fluent sentences but can understand written and spoken words.  The occipital lobe is located at the very back of the brain and is involved in processing visual information, which includes seeing colors and perceiving and recognizing objects, animals, and people. The primary visual cortex, which is located at the very back of the occipital lobe, receives electrical signals from receptors in the eyes and transforms these signals into meaningless basic visual sensations, such as lights, lines, shadows, colors, and textures. The visual association area, which is located next to the primary visual cortex, transforms basic sensations, such as lights, lines, colors, and textures, into complete, meaningful visual perceptions, such as persons, objects, or animals.  LIMBIC SYSTEM The hypothalamus regulates many motivational behaviors, including eating, drinking, and sexual The thalamus is involved in responses; emotional receiving sensory information, behaviors, such as doing some initial processing, and arousing the body when then relaying the sensory fighting or fleeing; and information to areas of the cortex, the secretion of including the somatosensory cortex, hormones, such as primary auditory cortex, and occurs at puberty primary visual cortex. The amygdala (ah-MIG-duh-la), located in the tip of the temporal lobe, receives input from all the The hippocampus, which is a curved senses. It plays a major role in evaluating the emotional structure inside the temporal lobe, is involved in significance of stimuli and facial expressions, especially saving many kinds of fleeting memories by putting those involving fear, distress, or threat them into permanent storage in various parts of the brain. Superior and inferior colliculus The midbrain contains two small structures (the superior colliculus and the inferior colliculus) that are important for relaying sensory information to the brain, and for movement control (including eye movements). Substantia nigra a crucial part of the dopamine-containing pathway (also referred to as the ‘reward- pathway’). It is the substantia nigra that deteriorates in Parkinson’s disease. HINDBRAIN The pons functions as a bridge to transmit messages between the spinal cord and brain. The pons also makes the chemicals involved in sleep (Monti et al., 2008). The Reticular formation A system of ill-defined nerve paths and connections within the brain stem, lying outside the well-defined nerve pathways, and is important as an arousal mechanism. The medulla, which is located at the top of the spinal cord, includes a group of cells that control vital reflexes, such as respiration, heart rate, and blood pressure. The cerebellum, which is located at the very back and underneath the brain, is involved in coordinating motor movements but not in initiating voluntary movements  Thyroid. This gland, which is located in the neck, regulates metabolism through the secretion of The pituitary gland, a key component of hormones. the endocrine system, hangs directly below the hypothalamus, to which it is connected by a narrow stalk. The pituitary gland is Adrenal glands. The adrenal cortex (outside divided into anterior (front) and posterior part) secretes hormones that regulate sugar (back) sections and salt balances and help the body resist stress; they are also responsible for growth of pubic hair, a secondary sexual characteristic. The adrenal medulla (inside part) secretes two hormones that arouse the body to deal with stress and emergencies: epinephrine (adrenaline) and norepinephrine (noradrenaline). Posterior pituitary. The rear portion of the pituitary regulates water and salt balance. Gonads. In females, the ovaries produce Anterior pituitary. The front part of the hormones that regulate sexual development, pituitary regulates growth through secretion ovulation, and growth of sex organs. In of growth hormone and produces hormones males, the testes produce hormones that that control the adrenal cortex, pancreas, regulate sexual development, production of thyroid, and gonads sperm, and growth of sex organs. Pancreas. This organ regulates the level of sugar in the bloodstream by secreting insulin.