PSYC 1101 Module 2 - With Dr. C PDF

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With Dr. C...

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PSYC 1101 Module 2 Nervous system ● Complex combination of neurons that communication with one another Learning objectives 1. Differentiate and describe the central nervous system and the peripheral nervous system, the somatic and autonomic nervous systems, and the sympathetic and parasympathetic nervous systems. 2. Locate and explain the different lobes of the brain and their function. 3. Summarize the process of an action potential. 4. Construct a model of a neuron and explain the major neurotransmitters and their role. 5. Correlate disorders with dysfunction of the brain. 6. Understand how dysfunction of the brain can cause impairment in daily living. To-do lists: ● Reading - Chapter 2, The Biology of the Mind ● Lessons ○ Neural Activity ○ Central Nervous System and Brain Anatomy ● Discussion - How do you think having prosopagnosia would affect your life? ● Assignment - LaunchPad assignments for Chapter 2 ● Activity - Voicethread: Create a Model of a Neuron ● Psychology 12e, Chapter 2 - This chapter will provide information on how neurons communicate with one another. It discusses the nervous and endocrine systems, as well as brain structure and function. ● Psychology 12e, LaunchPad - You will complete LaunchPad quizzes for Chapter 2, which will help you learn and consolidate the material. You can take the quizzes as many times as you want. You just need to achieve 51% or higher on each of them to get full credit for completion ● Chapter 2 ○ Learning Curve 2A ○ Learning Curve 2B ○ Chapter 2 Quiz Neurons and Neural Activity ● Damage to these areas = dysfunctional, unable to communicate Biological Psychology ● Links biology and behavior ● Looks @ physical and chemical changes involved in behavior & mental processes

PSYC 1101 Module 2 Nervous System ● Complex combination of cells telling you what’s going on inside & outside your body = makes you responsive eg burning hand on stove Information Processing System ● Input: sensory signals from outside world ● Processing: integrate info w past experiences and decide what to do ● Output: brain activates muscles or responses to act on input info (sensory systems) ● Achieved by cells communicating w each other Brain Anatomy ● Central nervous system → brain & spine ● Peripheral Nervous System ○ Somatic ○ Autonomic ■ Sympathetic ■ Parasympathetic

Neurons ● ~140 billion ● Transmits info

PSYC 1101 Module 2 ● Nerve Cell ● Main functional cell of CNS ● Specialized to quickly respond to and send signals ○ Sensory neurons - carry messages from body tissues and organs to brain and spinal cord ○ Motor neurons - carry messages from brain and spinal cord to muscles and glands ○ Interneurons - w brain and spinal cord communicating internally and intervening between sensory inputs and motor outputs ● Use neurotransmitters released into synaptic cleft ● Neuronal Structure (CAADA) ○ Cell body ■ Organized and keeps cell functional ○ Axon ■ Transfers signals to other cells & organs ○ Axon Terminal ■ Forms functions w other cells ○ Dendrites ■ Receive signals from other cells ○ Axon Hillock ■ Generates impulse in neuron

PSYC 1101 Module 2

Cell Membrane ● Selectively permeable (liquids and gas can pass through) to ions (molecules with +/electrical charge) ● Neuron at rest ○ 70mV inside relative to outside (normal cell pumps + charged molecules out) ○ High concentration of NA+ outside ○ High concentration of K+ inside ● Changes in environment = depolarizing cell = opening gates and sodium centers cell ● Continues down the axon ● An action potential - change in potential Action Potential ● Threshold level of depolarization is reached ● NA+ channels open allowing NA+ to rush in ○ Causes inside to be “less” negative ● Repolarization occurs when K+ channels open = K+ leave cell = “less” positive on inside ● All or none phenomenon ● Begins intercellular communication ● Rate of firing can vary depending on diameter of axon (larger = faster) and myelin sheath ● = Neurotransmitter release

PSYC 1101 Module 2

Action Potential ● Changes in environment around cell can depolarize membrane ○ = gates open and sodium enters cell = depolarization (inside of cell is less negative) ○ = Next area of axon depolarizes = neighboring gates open = creative wave of electrochemical potentials spreading down axon

PSYC 1101 Module 2

Lesson 2: Action Potential Video

PSYC 1101 Module 2 Parts of the Neuron w Functions

1) 2) 3) 4)

Dendrites - receive messages from other cells Nucleus - controls entire nucleon Cell body - organizes and keeps cell functional Cell membrane - protects cell

PSYC 1101 Module 2 5) Axon hillock - generates impulse in the neuron 6) Axon - transfers signals away from cell body to neurons, muscles or organs 7) Myelin sheath - covers axon and increases spread of signal 8) Node of ranvier - allows diffusion of ions 9) Schwann cell - produces myelin sheath 10) Axon terminal - forms junctions w other cells Action Potential

1. Step #1 - Axon in resting state & interior is negative 2. Step #2 - Sodium channels open up and sodium goes into axon, makes interior positive = depolarization 3. Step #3 - Potassium channels open up, potassium flows out of axon, makes interior positive = repolarization 4. Step #4 - Cell is hyperpolarized, sodium-potassium pumps restore axon to its resting potential 5. Step #5 - Axon returns to resting state Synapse and Neurotransmitters Synapse

PSYC 1101 Module 2 ● Presynaptic element has neurotransmitters → when an action potential reaches end of an axon, a neurotransmitter released into the synapse ○ → Postsynaptic element (contains receipts for the neurotransmitter, which “binds” to receptor) ○ → Stimulates channels in membrane of postsynaptic cell to open = change in membrane potential Anatomy of a synapse

Synapse - Neurotransmission ● Postsynaptic potential = Change in membrane potential of postsynaptic cell ○ Makes neuron more or less likely to fire ● Excitatory postsynaptic potential (EPSP) causes depolarization (+ ions flow into neuron) in postsynaptic element ● Inhibitory postsynaptic potential (IPSP) causes hyperpolarization (+ ions flow out of neuron) in postsynaptic element Neurotransmitter after synapse ● Postsynaptic potential spreads along membrane of postsynaptic cell ● Unlike action potential in an axon which remains at a constant strength, postsynaptic potential fades as it goes along ● One EPSP will generally not cause neuron to fire → but the combined effect of quickly repeated potentials or potentials from many locations can create strong enough signal to reach junction of axon and cell body ● Neurotransmitters may experience re-uptake before reaching receptor sites ● May also be broken down by enzymes waiting for them in cleft Major neurotransmitters 1. Acetylcholine - peripheral and central nervous systems

PSYC 1101 Module 2 ● Muscles, limbic system & memory ● Alzheimer’s 2. Norepinephrine ● Locus coeruleus (central nervous system) ● Learning, sleep & regulation of mood 3. ● ● ●

Serotonin Raphe nucleus (central nervous system) Made from tryptophan from food Regulation of mood and sleep-wake cycle

4. Gamma-amino butyric acid (GABA) ● Major inhibitory CNS neurotransmitter ● Severe anxiety, Huntington’s disease and epilepsy 5. Dopamine ● Substantia nigra - movement, sensation of pleasure, reward, memory & emotion ● Parkinson’s disease & schizophrenia 6. Glutamate ● Most common excitatory CNS neurotransmitter ● Learning 7. Endorphins ● Found throughout CNS ● Produces euphoria & analgesia Biology of the Brain: Divisions of the Nervous System Central Nervous System ● Surrounded in bone, including brain and spinal cord ● CNS is the “central executive” ● Info sent to CNS to be processed and acted on ● Spinal cord (SC) ○ Small diameter, ~42 cm in length ○ Neurons in SC get info from peripheral senses and sends that info to brain & back down to muscles

PSYC 1101 Module 2 ○ Reflexes → SC cells can do some simple behaviors without brain instructions, eg touching sth rly hot = info sent immediately to SC = immediate reflex, info not sent to brain ○ Sensory neurons - afferent (coming in) - process info coming in from outside world ○ Motor neurons - efferent (going away) - transmit info from CNS back to muscles & organs Peripheral Nervous System ● Part of nervous system not in bones ● Carries out sensory and motor function Brain Anatomy - Hindbrain ● Brainstem ○ Oldest part of brain ○ Does automatic functions eg heartbeat, breathing ○ Contains ■ Medulla (the base) ■ Pons (integration of movement between right and left) ■ Cerebellum ● Helps us w voluntary movement and balance → ataxia ● Procedural memory ● May be involved in higher order processing ● Midbrain ○ Reticular Formation ○ 90+ nuclei ○ Reticular Activating System ■ Responsible for consciousness, arousal, wakefulness ■ If damage = coma-like state (bcs u can’t be aroused) ● Diencephalon ○ Thalamus ■ Relay station ■ Transmits sensory info, EXCEPT OLFACTION ○ Hypothalamus ■ Hunger, thirst, sex, sleep, body temp, movement & emotional reactions ■ Damage = uncontrollable laughter or intense rage/aggression ■ Suprachiasmatic nucleus - mediates sleep-wake cycle ■ Reward center → eg drug highs ● Telencephalon

PSYC 1101 Module 2 ○ Basal Ganglia ■ Caudate nucleus, putamen, globus pallidus & substantia nigra ■ Involved in sensorimotor learning and in stereotyped expressions ■ Damage = basal ganglia disorders = Huntington’s (uncontrolled spasms) Parkinson’s (difficulty initiating movements), Tourette’s (ticks) ○ Limbic system ■ Responsible for emotions & drives ■ Amygdala (emotion; damage = Kluver-bucy syndrome = reduced fear/aggression, increased docility, oral exploratory behaviors, and hypersexuality) ■ Septum - inhibitory effect on emotion ■ Cingulate gyrus - satisfaction and pain felt here ■ Hippocampus ○ Hippocampus (HC) ■ In temporal lobe ■ Learning & memory ■ Case of patient HM: ● Bilateral remove of HC ● After surgery, patient can’t form new memories, past memories & procedural learning intact Brain Anatomy and Function Cerebral Cortex ● Left & right hemispheres ○ Mirror images of each other ○ Separated by interhemispheric fissure ○ Surface composed of sulci and gyri (folds and bridges of brain) ● Surface features → gyri and sulci makes our brain fold and not as big bcs evolution ○ Gyri = ridges ○ Sulci = grooves between gyri ● Protected by skull and three meninges (dura, arachnoid, pia) ● Left hemisphere ○ Language ○ Manipulation of number facts ○ Details ○ Fine motor skills ● Right hemisphere ○ Complex visuospatial skills ○ Face ID

PSYC 1101 Module 2 ○ Spatial distribution of attention ○ Emotional behavior ○ Non-lang aspects of attention ● Brain’s 4 lobes ○ Frontal → responsible for higher order processes that discerns humans from other species eg abstract reasoning ■ Motor cortex = initiation of voluntary movements ■ Broca’s area = production of written & spoken speech (damage = aphasia, can think ab what to say, can’t produce the words) ■ Prefrontal cortex = personality, behavior, cognition (from pole to 3rd frontal convolution) ■ Apraxia ■ Dysfunctions ● Depression, show/experience emotion ● Fine motor movements ● Reduced spontaneity ● Poor response inhibition ● Personality & social behavior ● Disturbance in speech production ● Early clues a PFC function: Phineas Gage ○ Parietal = processing spatial info/organization, mathematical and spatial reasoning and spatial organization of attention ○ Temporal = processing primary auditory info, learning and memory, comprehending speech ■ Dysfunction = impaired long-term memory, auditory perception, organization and comprehension of verbal material ○ Occipital = processing visual info (damage = agnosia, prosopagnosia → brain can’t interpret visual info bcs legions in occipital, even tho vision intact) ○ Corpus Callosum ■ Large fiber bundle connecting 2 hemispheres ■ Has ~300 bn axons, connects mirror image hemispheres Cerebral Cortex

PSYC 1101 Module 2

● 1 = Frontal (higher processes that distinguish humans from other species) ○ Thinking & planning ○ Organizing ○ Multi-tasking ○ Problem-solving ○ Emotional regulation ○ Inhibition (self-control(?)) ○ Personality ○ Producing language ● 2 = Motor and Sensory Cortex = movement and sensation ● 3 = Parietal = perception, visuospatial, arithmetic ● 4 = Temporal = learning, episodic and semantic memory, receptive language

PSYC 1101 Module 2 ● 5 = Occipital = visual reception & integration, color perception ● 6 = Cerebellum = balance, coordination, procedural memory ● 7 = Brainstem = breathing, heart rate, temperature Sensation Without Perception: Visual Prosopagnosia Video Notes I imagine having prosopagnosia as constantly entering a room where everyone either looks completely different, like nobody you have ever seen before, or too alike to discern one individual from the other. Either way, it must be extremely frustrating walking into any room, even one filled with your loved ones and the people closest to you, and not recognizing their faces. You try to adopt and practice coping strategies, such as asking your family and close friends to wear a distinctive piece of clothing so you can recall them, but people are flawed and people forget, and you feel burdened to constantly remind them to wear that one scarf just so you can know who your sister is. This, amongst several other frustrations, is what I imagine those diagnosed with prosopagnosia must experience on a daily basis. I imagine having this condition would hold a powerful potential to significantly damage your social relationships. I imagine having to rely on other senses, such as memorizing voices, clothes, hairstyles and having to be more attentive to the “little things.” As a result, this can place someone in isolation, and in extreme cases, those diagnosed with visual prosopagnosia can develop mental health issues, such as social anxiety, forcing them to socially withdraw in fear of offending people or the inability to keep up with friends. In worse cases, it can be a significant liability in one’s competence at work. Being unable to recognize your peers or even your boss must be frustrating and this must affect the careers of those in ways I cannot imagine. Putting aside one’s career path, it must also be frustrating in everyday life, such as not being able to recognize your regular barista, so you fear coming off rude and develop anxiety as a result, or not being able to easily follow movies, TV shows, or sports as easily as those around you do and feeling behind as a consequence. The small aspects of life, like watching a basketball game, can come with difficulties as you are forced to identify your favorite players by relying on the jersey number or body build because of the inability to recognize faces. These are only a few of the several frustrations I imagine those with prosopagnosia must live with, and learn to adjust their life according to and adapt to. LaunchPad Assignments Chapter 2: Introduction ● Phrenology = had no scientific basis = faded, but taught us about critical thinking in science; success in focusing attention on the functions of different brain regions ● Biological psychologist = scientific study of links between biological (genetic, neutral, hormonal) and psychological processes ● Adaptive brain is wired by experiences

PSYC 1101 Module 2 ● Nerve cells conduct electricity and transmit chemical messages across a tiny gap separating them ● Specific brain systems have specific functions ● Integrate info processed in diff brain systems for our experience of sights, sounds, meanings, memories, feelings ● We are biopsychosocial systems Power of Plasticity ● Brain’s ability to change by reorganizing after damage or building new pathways bcs new experiences eg well-practiced pianists have larger-than-usual auditory cortex area (sound-processing area) ● Hippocampus (memory center w spatial memories) can get bigger ● Brains change overtime, build patterns according to experience Neurons ● Nerve cell acting as the basic building block of the nervous system ● Neuron structure ○ Cell body and branching fibers = has nucleus  (cell’s life-support center) ○ Dendrites = bushy, branching extensions receiving and transmitting signals, conducting impulse toward the cell body ○ Axon = from dendrite, axon passes message through branches to other neurons/muscles ■ Dendrites listen, axons speak ■ Some surrounded in a myelin sheath = fatty tissue layer surrounding axons of some neurons, enables faster neural transmission ● If myelin sheath degenerates = multiple sclerosis (communication to muscles slows = eventually lose muscle control) ○ Glial cells = cells in nervous system protecting neurons and playing a role in learning, thinking & memory ■ Transmit info and play a role in memory by “chatting” w neurons; Neurons queen bees, glial cells worker bees ● Neural Impulse ○ Neurons transmit info when stimulated by our senses & other neurons ○ Action potential = a neural impulse involving an electrical charge travelling down an axon (how a neuron sends a message) ○ In neurons chemistry-to-electricity process, ions (electrically charged atoms) exchanged ○ Axon ■ Fluid outside axon’s membrane mostly positively charged sodium ions

PSYC 1101 Module 2

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■ Resting axon’s fluid interior (large, negatively charged protein ions and smaller, positively charged potassium ions) has mostly - charge ■ Surface = selectively permeable, allowing resting potential, wherein positive-outside/negative-inside state ■ When neuron fires → first section of axon opens gates and + charged sodium ions (attracted to negative interior) come through now-open channels; depolarization = loss of inside/outside charge difference Bodily sensations and actions happen when neurons stimulated enough that membrane’s electrical charge reaches a threshold → neurons “fire” an impulse, the action potential → travels down to axon and transmits message to other neurons/muscles Neural signs = Excitatory or inhibitory ■ If excitatory signals exceed inhibitory signals by a threshold (level of stimulation needed to trigger a neural response), the combined signals = action potential → travels down axon → branches into junctions with many other neurons or w/ muscles Refractory period = when neurons need a resting pause → action potentials can’t happen until axon returns to resting state and neuron can fire again Neuron’s reaction is all-or-none response (neuron’s reaction of either firing or not firing); increasing stimulation above threshold does not increase neural impulse’s intensity like how squeezing a trigger harder won’t make a bullet go faster

Revisions ● When a neuron fires an action potential, info travels through dendrites → cell body → axon ● Nervous system allows us to experience diff between a slap and tap on back bcs stronger stimuli (slap) = more neurons to fire and more frequently than w weaker stimuli (tap) How Neurons Communicate ● Synapse = meeting point between neurons (specifically axon tip of sending neuron and dendrite or cell body of receiving neuron) ○ Synaptic cleft/gap = tiny gap at synapse ○ Neurotransmitters cross tiny space between a neuron and the next neuron’s dendrite or cell body ● Neurotransmitters = chemical messengers crossing synaptic gaps between neurons; when released by the sending neuron, neurotransmitters travel across the synapse and bind to receptor sites on the receiving neuron, potentially causing neuron to make a neural impulse

PSYC 1101 Module 2 ● Reuptake = Excess neurotransmitters drift away, broken down by enzymes, reabsorbed by sending neuron Biology of antidepressants ● Selective serotonin reuptake inhibitors (SSRIs) = antidepressants, by partially blocking reuptake of neurotransmitter serotonin Neurotransmitters Influence Us ● Interact and effects vary with receptors they stimulate; neurotransmitters such as: ● Acetylcholine (ACh) = enables muscle action, learning, memory; damage = Alzheimer’s ○ Messenger at every junction between motor neurons (which carry info from brain and spinal cord to ...