Biopsychology

chapter 3

Biopsychology: the biological mechanisms that underlie behavior.

  • Genetics

  • Nervous System Structure + Endocrine system and how they interact

  • Life-span development

Evolutionary Psychology: focuses on how universal patterns of behavior and cognitive processes have evolved over time.

Behavioral Geneticists: study how individual differences arise, in the present, through the interaction of genes and the environment.

PET scans: creates pictures of the living, active, brain.

CT scans: taking a number of x-rays of a particular section of a person’s body or brain.

  • tumor or atrophy in the brain

MRI: uses a strong magnetic field to jostle unsettled hydrogen atoms, which then settle on different densities and make a picture.

fMRI (functional Magnetic Resonance Imaging): shows changes in brain activity over time by tracking blood flow and oxygen levels.

  • Better accuracy + more detail than a PET scan

Electroencephalography (EEG): using caps with nodes, modern EEG research can study the precise timing of overall brain activities.

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Genetics:

Why do two people with the same disease have different outcomes?

Predispositions to disease (depression, anxiety, heart disease, etc.)

Charles Darwin—the most adaptable species survives

Chromosome: long string of genetic information known as DNA

DNA: all the pairings of the chromosomes; communicate with each other

Allele: specific version of a gene

Gene: sequence of DNA that controls/partially controls physical characteristics known traits

  • Genotype: genetic makeup (cannot see). Where they communicate.

  • Phenotype: observable characteristics (hair, eyes, skin).

Mutations: sudden, permanent change in a gene. Can happen at ANY time. 😥

  • can be good

  • lactose tolerance is a mutation

OLD THOUGHT:::::: Range of Reaction: our genes set the boundaries within which we can operate, and our environment interacts with the genes to determine where where in that range we fall.

  • You have support, you succeed. You don’t, you fail.

Genetic Environmental Correlation: if certain individuals are exposed to something in their environment, it influences the expression of our genes.

  • T.V. show

Epigenetics: study of gene-environment interactions

  • ex: How the same genotype leads to different phenotypes.

Range of Reaction: our genes set the boundaries within which we can operate, and our environment interacts with the genes to determine where in that range we will fall.

Neuron Structure

TATO’S BOOK

Terminal Buttons contain synaptic vessels.

Synaptic Vessels: storage sites for chemical messengers called neurotransmitters.

Neurotransmitters: finite, reabsorbable; chemical message of the nervous system

Synapse: the space between the terminal button of one neuron and the dendrite of another neuron.

  • There can be not enough transmitters produced—bc they are made of proteins

  • They could be unbalanced

Depolarization: membrane potential becomes less negative making the neuron more likely to fire (excitation).

Hyperpolarization: membrane potential

Threshold of excitation: serotonin kick, beta endorphin; a level to indicate the neurons becoming active.

Action Potential: the electrical signal that typically moves from the cell body down the axon to the axon terminals. (Positive spike). All-or-none phenomenon.

  • when the action potential arrives at the terminal button, the synaptic vesicles release their neurotransmitters into the synaptic cleft.

  • Once the signal is delivered, excess neurotransmitters in the synaptic cleft drift away, are broken down into inactive fragments, or are reabsorbed in a process known as reuptake.

Reuptake: when the neurotransmitter gets pumped back into the neuron that released it, in order to clear the synapse.

Neuronal Membrane:

  1. Membrane Potential: the difference in charge between intra- and extracellular fluids (ex: cytoplasm); provides energy for the signal.

                i) The electrical signals that passes through the neuron depends and differs                    depending on if it’s in intra- or extracellular fluids. The neuronal membrane keeps                    intra- and extracellular fluids separate.

  1. Resting Potential: when the neuron membrane’s potential is held in a state of readiness between signals.

Biological Perspective: studying the physiological causes of behavior that psychological disorders like depression and schizophrenia are associated with imbalances in one or more neurotransmitter systems.

Acetylcholine: muscle action and memory

Beta-endorphin: pain and pleasure

Dopamine: mood, sleep, and learning

Norepinephrine: Heart, intestines, and alertness.

Serotonin: mood and sleep

Gamma-aminobutyric acid (GABA): brain function and sleep

Glutamate: increase in learning, memory

DRUGS

Psychotropic medication: drugs that treat psychiatric symptoms by restoring neurotransmitter balance.

  • Agonist—drug that mimics or strengthens the effect of a neurotransmitter

    • Depression

  • Antagonist—drug that blocks or impedes the normal activity of a given neurotransmitter

    • Schizophrenia (hyperactivity; too much dopamine)

Nervous System

TATO’S BOOK

Nervous System: glial cells and neurons.

Glial Cells: support, protect, nourish neurons; transport nutrients and waste products, and mediate immune responses.

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How does a neurotransmitter “know” which receptor to bind to?

The neurotransmitter and the receptor have 3.2 • Cells of the Nervous System 79 what is referred to as a lock-and-key relationship—specific neurotransmitters fit specific receptors similar to how a key fits a lock. The neurotransmitter binds to any receptor that it fits.

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Endocrine System: series of glands that produce chemical substances known as hormones.

  • neither part of the CNS or PNS

  • uses chemical signaling

a) Central Nervous System (CNS)— brain and spinal cord

Brain: billion of interconnected neurons and glia, bilateral, lobes that interact

  • uses electrical signaling

Neuroplasticity: how the nervous system can change and adapt

Lateralization: concept that each hemisphere of the brain is associated with specialized functions

  • left side controls the right side of the body, Right side controls the left side of the body

Corpus Callosum: middle between the two hemispheres. connects them. bunch of neurons and communicators

Forebrain, Midbrain, and Hindbrain

Forebrain: largest part of the brain.

  • Cerebral cortex—higher level process (the surface of the brain/what we see)

  • Thalamus—sensory relay

  • Hypothalamus—regulates sexual motivation. Maintains homeostasis via regulation of hormones (it produces the hormones that regulate everything; body temp, hunger, heart rate, mood). Acts as an interface between the nervous and endocrine system.

  • Pituitary Gland—produces key hormones that regulate fluid levels in the body, and messenger hormones. Of which direct the activity of other glands in the endocrine system. Controls other hormone glands

  • Limbic System—collection of structures involved in processing emotion and memory

Midbrain: comprised of structures located deep within the brain, between the forebrain and the hindbrain.

  • Reticular formation: regulates sleep/wake cycle, arousal, alertness, and motor activity.

  • Substantia nigra + Ventral tegmental area (VTA): have cell bodies that produce neurotransmitter dopamine; critical for movement functions.

    • degradation of these = Parkinson’s disease

Hindbrain: back of the head; almost extension of spinal cord.

  • Medulla: controls the automatic processes of the autonomic nervous system: breathing, blood pressure, and heart rate.

  • Pons: connects the hindbrain to the rest of brain. regulates brain activity during sleep.

  • Cerebellum: receives messages from muscles, tendons, joints, and structures in our ear to control balance, coordination, movement, and motor skills.

    • Functional Memory Processing; ADHD issue that i have :P

Frontal lobe: responsible for executive function, (planning, organization, judgement, attention, reasoning), motor control, emotion, and language.

  • motor cortex strip (control motor)

  • prefrontal cortex: higher level cognitive functions

  • Broca’s area: language (left hemisphere)

Phineas Gage: a hot iron rod exploded through his face (frontal lobe) at a railroad construction site. He was lying in a pool of his own blood and there was his brain matter on the ground, but he was conscious and able to get up, walk, and speak.

  • his personality changed (with the damage to his impulse control/frontal lobe damage)

Parietal Lobe: right behind the frontal lobe, and it processes information regarding the body’s senses.

  • somatosensory cortex

Temporal Lobe: the side of the head (migraine area :P), associated with hearing, memory, emotion, and some aspects of language.

  • auditory cortex: auditory processing information

  • Wernicke’s area: speech comprehension

    • ppl with damage to this can speak, but not understand

Occipital Lobe: back of brain, visual processing/interpretation

Spinal Cord: delivers messages to and from the brain

  • has its own system of reflexes

  • merges with the brain stem and ends just below the ribs

Limbic System: involved in processing both emotion and memory. Sense of smell bc smells triggers memory.

b) Peripheral Nervous System — PNS

  • Somatic: relays sensory and motor information to and from the CNS

  • Automatic: controls our internal organs and glands and can be divided into Sympathetic and Parasympathetic

    • Sympathetic: involves stress-related activities; fight or flight

    • Parasympathetic: routine, day-to-day operations of the body under relaxed conditions

      • Your body should always be resting and relaxing

        • peeing at night and not being able to stop