PSYINTRO Chapter 2 Exam Reviewer PDF

The Nervous System The fight or flight response can cause Source: Nervous System increased heart rate and increased The two regions of the nervous system breathing. It can also cau...

The Nervous System The fight or flight response can cause Source: Nervous System increased heart rate and increased The two regions of the nervous system breathing. It can also cause other areas to The central nervous system (CNS) not be active like the digestive system The peripheral nervous system (PNS) because it’s not important to the current CNS (central nervous system) situation Consists of the brain and spinal cord Parasympathetic system Can process the sensory information from Known as rest and digest the PNS and act as a command center Heart rate will decrease and digestion will Can execute motor responses or regulate occur body mechanisms The three regions of the brain (BRAIN STEM) PNS (peripheral nervous system) Hindbrain Consists of all other components of the Midbrain nervous system, such as nerves throughout Forebrain the body Hindbrain Can provide sensory information for the Includes the medulla, pons, and CNS — it’s a communication network cerebellum Divided into the somatic nervous system The medulla has many regulation (SNS) and autonomic nervous system functions, such as the regulation of (ANS) breathing, blood pressure, and heart rate SNS (somatic nervous system) The pons are involved with some of these Involved with the motor functions of types of functions as well. It also skeletal muscle coordinates signals with this area to the Includes voluntary actions under rest of the brain conscious control but also somatic reflexes The cerebellum has the functions of that involve skeletal muscle balance and muscle coordination ANS (autonomic nervous system) Midbrain About what’s going on in the internal Involved in alertness and the sleep/wake environment in regard to gastrointestinal, cycle, motor activity, and more excretory, endocrine, or smooth and Forebrain cardiac muscle Includes the cerebrum, which itself is ○ E.g., breathing, dilating, secreting, divided into two hemispheres: right and digesting, etc. left Includes autonomic reflexes ○ The cerebrum regulates our Is further divided into the sympathetic and speech, our thinking and parasympathetic systems reasoning, our sensing, and our Sympathetic system emotions depending on the Part of the quick fight or flight response specific location  Includes the thalamus, which is involved cells — this is essential for with sensory and motor information signaling Includes the hypothalamus, which has ○ Maintain the blood-brain barrier, major control of the endocrine system which keeps a lot of substances in Two major types of cells in the nervous system that the body from getting into the make up nervous tissue nervous system Found in both the CNS and PNS ○ Make myelin, which goes around Neurons the axons of neurons as something called a myelin sheath A myelin sheath insulates the axon and transfers the signal ○ Produce cerebrospinal fluid, which is protective of the brain and essential for homeostasis as well as many other critical functions ○ Have an important immune function in the nervous system Resting potential When the neuron is at rest, there is no signal being carried. At rest, a neuron has something called resting potential The resting potential of a neuron is more ○ Cell body: the nucleus and most negative than its surroundings. It’s other organelles are here generally around -70 millivolts, meaning ○ Dendrites: these branched that it has an electrical charge structures are where signals are It has an electrical charge because there are received ions involved inside and outside of the cell. ○ Fiber: the area where a signal will These ions — specifically, sodium and normally be carried away to some potassium — play huge roles in keeping other cell the resting potential ○ Synapse: the junction area where Ions found in resting potential the neuron will be ○ Chloride (Cl-) communicating with another cell ○ Sodium (Na+) Glial cells (glia) ○ Potassium (K+) ○ Help the neurons connect in place ○ Certain anions (A-) ○ Keep a balance of certain At rest, the sodium (Na+) concentration is chemicals in the space between generally higher outside of the cell and the  potassium (K+) concentration is higher inside the cell ○ REMEMBER: It’s Kool to be K+ resting in the cell Overall, at rest, the neuron is more negative inside compared to its surroundings Action potential The action potential is considered an “all Allows neurons to communicate with each or none” thing. It either happens or it other. In order to communicate, neurons doesn’t have to be able to receive a signal in the Neurotransmitters dendrite and carry it down the axon After the action potential goes down the The dendrite of the neuron receives a axon and gets to the axon terminals (the signal → action potential generates along ends of the axon), it signals synaptic the axon → this potential changes the vesicles in that neuron to release charge in the neuron along the axon neurotransmitters Depolarization: the event where the Synapse: the area between the two neurons neuron’s electric charge becomes more There are different types of positive in the axon as Na+ (positive ion) neurotransmitters and they can be derived floods in while most of the K+ channels from different substances stay closed ○ E.g., amino acids, amino acid Repolarization: After the action potential precursors, gases like nitric oxide, spreads to a new region of the axon, the old etc. region starts to be restored. During this Types of neurotransmitters process, K+ ions leave the cell as the K+ ○ Glutamate channels open, helping to restore the ○ Dopamine inside of the neuron to a negative charge ○ Serotonin ○ GABA ○ Acetylcholine Generally, when neurotransmitters are released from the synaptic vesicles, the neurotransmitters only need to travel a small space between the neurons (the If neurons are myelinated — meaning they synaptic cleft) have myelin sheaths that insulate the axon Neurotransmitters bind to specific and assist with the transfer of the signal — receptors on the next neuron, matching the action potential can actually jump the type of neurotransmitter → the from node to node (areas where it’s not dendrites of the next neuron receive the myelinated)  signal → it can then start an action Axon: a fiber attached to the soma that potential across its axon transfers messages out to other cells Chapter 2: The Biological Perspective Axon terminals: they communicate with Neurons and Nerves: Building the Network other nerve cells Nervous system: a network of cells that Glia (glial cells) carries information around the body ○ Some serve as structures for Neuroscience: a branch of the life sciences neurons to develop and work that deals with the structure and ○ Help get nutrients to neurons functioning of the brain as well as the ○ Clean up dead neurons nervous system ○ Provide insulation for neurons Biological psychology/behavioral ○ Communicate with neurons and neuroscience: the branch of neuroscience that focuses on the biological bases of other glia psychological processes, behavior, and ○ Affect functioning and structure learning of the neurons Structure of the Neuron: The Nervous System’s ○ Some have properties of stem cells Building Block that let them develop into new neurons ○ Have two special types, Oligodendrocytes and Schwann Oligodendrocytes ○ Produce myelin for neurons in the brain and spinal cord (central nervous system) ○ More likely to be permanently damaged Most cells constitute Schwann ○ A nucleus ○ Produce myelin for neurons in the ○ A cell body body (peripheral nervous system) ○ A cell membrane that holds it all ○ Nerves: bundles of myelin-coated together axons that travel together as cables Neuron: a specialized cell that receives and ○ Myelin here can help repair and sends messages within the nervous system reconnect damaged nerves Dendrites: the parts of the neuron that Myelin sheath receive messages from other cells. They’re ○ An important part of the neuron attached to the cell body (soma) ○ Insulates and protects the neuron Soma: the part of the cell that contains the ○ Speeds up the neural message nucleus and keeps the cell alive and traveling down the axon functioning Multiple sclerosis (MS): the myelin sheath is destroyed (possibly by the individual’s  own immune system), leading to Neurons must have a way to be turned off diminished or complete loss of neural as well as on functioning The neurotransmitters at synapses can Generating the Message Within the Neuron: The either turn cells on (excitatory effect) or Neural Impulse turn cells off (inhibitory effect), depending Diffusion: ions move from areas of high on exactly what synapse is being affected concentration to areas of low Excitatory neurotransmitters have concentration excitatory effects on the neuron. This Electrostatic pressure: the relative electrical means they increase the likelihood that the charges when the ions are at rest neuron will fire an action potential. It’s Because of diffusion and electrostatic like stepping on the gas pedal of a car pressure, the charge of ions inside the cell is Inhibitory neurotransmitters have mostly negative, whereas the charge of ions inhibitory effects on the neuron. This outside the cell is mostly positive means they decrease the likelihood that the Since the cell membrane is semipermeable, neuron will fire an action. It’s like stepping some substances that are outside the cell on the brake can enter through tiny protein openings Refer to them as excitatory synapses and called channels inhibitory synapses instead The difference in charges (the positive Neurotransmitters: Messengers of the Network sodium ions on the outside of the cell and Antagonist: a chemical substance that the negative ions on the inside) creates an blocks or reduces the effects of a electric potential neurotransmitter ○ Inside the cell are smaller ○ An antagonist doesn't only inhibit positively charged potassium ions cell activity and larger negatively charged ○ If the antagonist affects an protein ions inhibitory neurotransmitter, it After an action potential, positive blocks the inhibitory effect potassium ions will quickly exit the ○ This results in increased cell neuron. This helps restore the cell's inside activity that would normally have to a negative charge been inhibited ○ I.e., the cell membrane pumps the Agonist: a chemical substance that mimics positive sodium ions back outside or enhances the effects of a the cell. Since this process is slow, neurotransmitter potassium ions inside the neuron ○ E.g., the antianxiety medication will move out of the cell so that diazepam increases the inhibitory the cell’s inside can go back to a (calming) action of GABA negative charge more quickly Acetylcholine (ACh) Sending the Message to Other Cells: The Synapse ○ Excitatory or inhibitory  ○ The first neurotransmitter to be ○ Alcohol is an agonist for GABA identified Norepinephrine (NE) ○ Stimulates the skeletal muscles to ○ Mainly excitatory ○ Deals with arousal and mood contract but actually slows Endorphins contractions in the heart ○ Inhibitory neural regulators In short, it controls ○ Deals with pain relief muscle contractions Neuropeptides: a group of substances that ○ Deals with memory, arousal, and can serve as neurotransmitters or attention hormones or influence the action of other ○ The drug curare acts as an neurotransmitters Cleaning Up the Synapse: Reuptake and Enzymes antagonist for ACh, whereas the Neurotransmitters must leave receptor venom of a black widow spider is sites before the next stimulation can occur an agonist for ACh Some neurotransmitters drift away Dopamine (DA) through diffusion ○ Excitatory or inhibitory ○ Deals with control of movement Most are reabsorbed into synaptic vesicles and sensations of pleasure through reuptake, clearing the synapse for ○ Too little DA → Parkinson’s the next release of neurotransmitters disease One neurotransmitter that can’t be taken ○ Too much DA → schizophrenia back into the vesicles is acetylcholine Serotonin (5-HT) (ACh) ○ Excitatory or inhibitory Since ACh controls muscle activity, which ○ Deals with sleep, mood, anxiety, and appetite must happen quickly, it can't wait for Glutamate reuptake. Instead, an enzyme breaks down ○ Major excitatory neurotransmitter ACh in the synaptic gap rapidly through ○ Deals with learning, memory enzymatic degradation formation, nervous system development, and synaptic plasticity Synaptic plasticity: the brain’s ability to change connections among its neurons ○ Too much glutamate → overactivation and neuronal damage Gaba-aminobutyric acid (GABA) Some drugs exert their agonistic or ○ Major inhibitory antagonistic effects by altering the amount neurotransmitter ○ Helps calm anxiety of neurotransmitter in the synapse ○ Deals with sleep and inhibits movement  These drugs interfere with normal ○ Efferent (motor) neurons reuptake or enzymatic degradation Carry messages from the processes spinal cord to the muscles and glands ○ Interneurons Connect the sensory neurons to the motor neurons (and make up the inside of the spinal cord and much of the brain itself) ○ REMEMBER: Afferent neurons An Overview of the Nervous System access the spinal cord; efferent neurons exit The Peripheral Nervous System: Nerves on the Edge Peripheral nervous system (PNS) ○ Made up of all the nerves and neurons that aren’t in the brain and spinal cord ○ Allows the brain and spinal cord to communicate with the sensory systems of the eyes, ears, skin, and mouth Spinal cord ○ Allows the brain and spinal cord ○ Serves two functions for the to control muscles and glands nervous system ○ Divided into two major systems The outer section carries The somatic nervous messages from the body system (SNS): it consists up to the brain and vice of nerves that control versa voluntary muscles The inside section deals The autonomic nervous with fast, lifesaving system (ANS): it consists reflexes. It’s made up of of nerves that control cell bodies separated by involuntary muscles, glia organs, and glands Three types of neurons Somatic nervous system (SNS) ○ Afferent (sensory) neurons ○ Controls the senses and voluntary Carry messages from the muscles senses to the spinal cord ○ Made up of  The sensory pathway: it targeting the heart, muscles, and comprises all the afferent lungs nerves carrying messages ○ Food digestion and waste from the senses to the excretion will be shut down CNS because they’re not necessary for The motor pathway: it dealing with stress comprises all the efferent Parasympathetic system nerves carrying messages ○ Located at the top and bottom of from the CNS to the the spinal column, on either side voluntary (skeletal) of the sympathetic division muscles neurons Autonomic nervous system (ANS) ○ Called the “eat-drink-and-rest” ○ Controls organs, glands (the system adrenal glands and the pancreas), ○ Returns the body to normal and involuntary muscles (heart, functioning after a stressful stomach, and intestines) situation ends ○ Divided into two systems: the Slows the heart and sympathetic division and the breathing parasympathetic division Constricts the pupils Reactivates digestion and excretion Signals to the adrenal glands stop ○ Allows the body to restore all the energy it burned Distant Connections: The Endocrine Glands Glands: organs that secrete chemicals Exocrine glands: glands that secrete their Sympathetic division chemicals directly onto the body’s tissues ○ Located in the middle of the through ducts. They affect the functioning spinal column of the body but don’t affect behavior ○ Called the “fight-or-flight system” ○ E.g., salivary glands and sweat because it allows people and glands animals to deal with stressful Endocrine glands: glands that have no events ducts and secrete their chemicals — their ○ The adrenal glands will be hormones — directly into the bloodstream stimulated to release stress Endocrine communication is slower than hormones into the bloodstream, synaptic communication because  hormones take longer to target organs; their effects might not occur until later on The Pituitary: Master of the Hormonal Universe Pituitary gland ○ The master gland that controls all other endocrine glands ○ Located in the brain below the hypothalamus ○ The hypothalamus controls the endocrine system by influencing the pituitary Hormones that are controlled by the pituitary ○ Oxytocin: the hormone that Figure of the endocrine system controls aspects of pregnancy Pineal gland Deals with reproduction ○ Secretes the hormone melatonin, and parental behavior which helps track day length and Stimulates the seasons contractions of the uterus ○ In some animals, this influences during childbirth seasonal behaviors such as Responsible for milk breeding and molting letdown reflex (the ○ In humans, melatonin levels are mammary glands more influential in regulating the contract to give milk to sleep-wake cycle the baby) Thyroid gland ○ Vasopressin: the hormone that ○ Secretes hormones that regulate controls levels of water in our growth and metabolism body ○ Plays a vital role in body and brain Helps the body conserve development water ○ A hormone called thyroxin ○ Growth hormone: the hormone regulates metabolism (how fast that controls and regulates the the body burns its available growth of children energy) ○ There are hormones that Pancreas stimulate the gonads (ovaries and ○ Secretes insulin and glucagon and testes) to release female or male sex controls the level of blood sugar in hormones the body ○ Too little secretion of insulin → diabetes  ○ Too much secretion of insulin → experiences physical or Hypoglycemia (low blood sugar) psychological stress Gonads ○ Are the sex glands and include the ovaries and the testes ○ Secrete hormones that regulate sexual behavior and reproduction ○ Don’t control all sexual behavior; the brain is the master of the sexual system due to psychological factors like attractiveness Adrenal glands ○ Divided into two sections: the adrenal medulla and the adrenal Looking Inside the Living Brain cortex [Insert notes here] ○ Adrenal medulla From the Bottom Up: The Structures of the Brain Releases adrenaline The Hindbrain (epinephrine) and The three divisions of the brain noradrenaline ○ Forebrain (norepinephrine) when Includes the cortex, basal people are under stress ganglia, and the limbic Aids in sympathetic system arousal ○ Midbrain ○ Adrenal cortex Deals with sensory Produces over 30 (senses) and motor different hormones called (muscles or glands) corticoids (aka steroids) functions Corticoids (aka steroids) ○ Hindbrain Regulate salt Includes the medulla, intake pons, and cerebellum Help initiate and control stress reactions Provide a source of sex hormones Cortisol, one of the most important adrenal hormones, gets released when the body  Medulla unchanging information (like ○ Controls life-sustaining functions background noise) such as heartbeat, breathing, and ○ Keeps people alert and aroused swallowing ○ The reticular activating system ○ Sensory nerves cross over in the (RAS), a part of the RF, medulla, meaning information stimulates the brain to stay awake from the left side of the body goes and alert to the right side of the brain, and The RAS is responsible vice versa for heightened attention Pons in sudden situations, ○ The bridge between the lower such as reacting to a car parts of the brain and the upper pulling out in front of parts you while driving Relay messages between Cerebellum the cerebellum and the ○ The part of the lower brain that cortex controls all involuntary, rapid, and ○ Motor nerves carrying messages fine motor movement from the brain to the body cross ○ Coordinates voluntary over in the pons. This allows the movements that have to be quick pons to coordinate the (e.g., walking, skating, etc.) movements of the left and right In short, it controls rapid sides of the body involuntary and ○ Influences sleep, dreaming, and voluntary movements arousal ○ Stores learned reflexes, skills, and habits, allowing them to be automatic Structures Under the Cortex: The Limbic System Forebrain ○ Contains the two cerebral hemispheres of the brain, including the cortex and the subcortical structures under the cortex Reticular formation (RF) ○ Subcortical structures deal with ○ A network of neurons between our thinking and behavior the medulla and pons Limbic system (THHAC) ○ Helps people focus on changing ○ Made up of subcortical structures information and ignore constant,  ○ Includes the thalamus, ○ Deals with learning and the ability hypothalamus, hippocampus, to compare sensory information amygdala, and cingulate cortex to expectations ○ Deals with emotions, motivation, ○ ACh, the neurotransmitter memory, and learning involved in muscle control, also deals with the memory function of the hippocampus Amygdala ○ Influences our motivation, emotional control, fear response, and interpretations of nonverbal emotional expressions ○ Information from the senses goes to the amygdala before it goes to Thalamus the upper part of the brain so that ○ Processes sensory information people can respond to danger very before sending it to the cortex that quickly deals with the sensation In short, it allows people ○ Damage to the thalamus might to respond to danger very result in the loss of sensation quickly ○ The sense of smell is unique ○ Plays a vital role in forming because signals from neurons in emotional memories; nonetheless, the sinus cavity go directly to the it’s unclear if the memories are brain’s olfactory bulbs stored in the amygdala ○ Smell is the only sense that doesn’t ○ Damaged amygdala → decreased have to pass through the thalamus fear response Hypothalamus Cingulate cortex ○ Regulates body temperature, ○ Deals with both emotional and thirst, hunger, sleeping and cognitive processing waking, sexual activity, and ○ Can be divided into four regions emotions that play different roles in ○ Controls the pituitary processing emotional, cognitive, Hippocampus (remember it like a Hippo and autonomic (involuntary) would!) information ○ Deals with forming long-term ○ Has been shown to be active declarative memories that are during tasks like selective stored in the brain attention, word recognition, and working memory  ○ Has been implicated in ○ The corpus callosum allows the psychological disorders such as left and right hemispheres to ADHD, schizophrenia, communicate with each other depression, and bipolar disorder ○ Contralateral organization: each hemisphere of the cortex controls the opposite side of the body E.g., the motor cortex in the left hemisphere controls the movement of the right hand ○ Some information, like hearing and vision, is processed by both sides of the brain (bilateral) ○ Other senses, like taste and smell, The Cortex are processed on only one side Corticalization: the brain gets more (ipsilateral) wrinkled as it increases in size and ○ These features are key to complexity. The wrinkling of the cortex understanding brain lateralization allows more cortical cells to exist in it (the view that different parts of the brain perform different functions) Occipital lobes ○ Process visual information in the primary visual cortex ○ The visual association cortex helps identify and make sense of the visual information from the eyes ○ In short, it mainly deals with sight Parietal lobes ○ Contain the somatosensory complex, which receives sensory Cerebral hemispheres information ○ The cortex is divided into two ○ Process information from the skin sections: the cerebral hemispheres and internal body receptors ○ Connected by a thick, tough band related to touch, temperature, and of axons called the corpus body position callosum ○ The somatosensory cortex is organized so that cells at the top receive signals from the lower  body, and as you move down, they ○ Humans also have mirror neurons receive signals from higher body in the brain parts ○ Found in both motor regions and ○ In short, it mainly deals with areas involved in vision and touch memory Temporal lobes The Association Areas of the Cortex ○ Contain the primary auditory Association areas cortex and auditory association ○ Made up of neurons in the cortex area ○ Connect sensory information ○ Helps process visual information with stored memories, images, ○ The left temporal lobe deals with and knowledge language processing ○ Help people make sense of the ○ The medial structures of the incoming sensory input temporal lobe, such as the Broca’s area amygdala and hippocampus, deal ○ Located in the left frontal lobe with learning and memory ○ Allows a person to speak ○ In short, it mainly deals with smoothly and fluently hearing ○ Called Broca’s area after Frontal lobes nineteenth-century neurologist ○ Handle higher mental functions Paul Broca, who first studied like planning, personality, people with damage to this area memory storage, complex ○ Damage to Broca's area leads to decision-making, and language Broca's aphasia, where a person ○ Help regulate emotions through can understand speech but connections with the limbic struggles to produce their own system words ○ The prefrontal cortex is the most Aphasia: the inability to forward part of the frontal lobes use or understand ○ Contains the motor cortex, which written or spoken controls voluntary muscle language movements by sending commands ○ Speech becomes halting, with to the somatic nervous system mispronunciations (e.g., "cot" Mirror neurons instead of "clock") and missing ○ A special type of neuron words (e.g., "the" or "for") ○ Fire when an animal performs an Wernicke’s Area action and when it observes the ○ Located in the left temporal lobe same action being performed by ○ Called Wernicke’s area after the another animal physiologist Carl Wernicke, who  first studied people with damage Processes information to this area simultaneously and ○ Deals with understanding the holistically meaning of words Understands simple ○ A person with Wernicke’s aphasia language but doesn’t would be able to speak fluently produce speech and pronounce words correctly, but the meaning of the words would be wrong The Cerebral Hemispheres: Are You in Your Right Mind? Split-brain research ○ Roger Sperry Was a pioneer in the field of hemisphere specialization Won a Nobel Prize for demonstrating that the left and right hemispheres of the brain specialize in different activities and functions ○ Left hemisphere Specializes in language, speech, handwriting, math, time, rhythm, and analytical thinking Processes information sequentially and breaks things down into parts ○ Right hemisphere Focuses on global processing like perception, visualization, spatial awareness, recognition of patterns, faces, emotions, melodies, and emotional expression