AP Psych U1: Biological Bases of Behavior

Psychology: 

• Scientific study of behavior and mental processes

 Behavior: 

• Any observable action, response, or conduct exhibited by an individual; includes both voluntary and involuntary

Introspection: 

• Self-examination or observation of one's own emotional states or thought processes; involves looking inward to analyze one's inner thoughts and feelings

  • Earliest technique used to study psychology 

    • Ask a subject to be aware of their feelings 

Correlations: 

• A statistical measure of the strength and duration of the relationship between two factors

  • In a positive correlation, the two factors rise and fall together. In a negative correlation, one factor rises, and the other one falls

False Consensus Effect: 

• A cognitive bias where individuals overestimate the extent to which their opinions, beliefs, preferences, values and habits are normal and typical of those of others

Hindsight Bias: 

• When you think you knew something all along after the outcome has occurred

Illusory correlation:

• A phenomenon that psychologists must avoid during experimentation

  • This correlation is when the person believes that a relationship exists between two variables when it does not

    • When you think there is a relationship between something when there is not

      • EX: U wore a lucky hat during a test and did good and now u wear it every test  

Independent and dependent variables:

• Dependent variable- outcome of the experiment that is being measured 

• Independent variable- is what makes the different research groups different from each other

Measures of central tendency :

• Statistical values that represent the center or typical value of a dataset

  • 3 M’s: Mean, mode, & median 

    • When all 3 numbers are the same===== Perfect standard deviation/bell-shaped curve 

Overconfidence:

• The tendency of an individual to overestimate their abilities and knowledge, leading them to make decisions without considering potential risks or negative outcomes

Placebo effect:

• A psychological phenomenon where a person experiences an improvement in their condition or symptoms after receiving a treatment that is inactive or doesn't have any therapeutic effect

Psychological perspectives: 

• a school of thought or a philosophy which would guide someone's interpretation of an individual's behavior

  •  a specific way of observing and understanding human behavior

Random assignment:

• Every participant having an equal chance of being in either the experimental group or the control group

  • a way of placing participants from your sample into different groups using randomization

Population:

• All individuals who share particular characteristics and can be considered as part of a larger group from which samples are drawn

Research methods:

• Experiments

  • Manipulates one or more independent variables to determine the effects of certain behavior

    • Can determine cause and effect

• Correlational Studies

  • Involved looking at the relationships between two or more variables and is used when performing an experiment is not possible 

    • Easy to conduct

    • Can not determine cause and effect

• Survey Research

  • Collection of information reported by people about a particular topic 

    • Cost effective

      • Low response rates

      • Naturalistic Observations

        • Researcher observes a subject’s behavior without interventions

          • Natural setting

• Case Study

  • An in-depth study of an individual or a small group.

    •  Usually, case studies are done on people with rare circumstances. For example, a girl named Genie was locked in her room, causing a delay in development. Researchers did a case study about her to understand more about language and human development stages 

      • Cannot generalize results to wider population

      • Difficult to replicate 

Correlation coefficient: 

• Measures the strength and direction of a linear relationship between two variables on a scatter plot

  • ranges from -1 to 1 

    • -1 indicates perfect negative correlation

    • 0 indicates no correlation

    • 1 indicates perfect positive correlation

Scatter plots:

• Shows the relationship between two quantitative variables measured for the same individuals

Operational definitions:

• a term that is used to describe the procedure of a study and the research variables

• Cross-sectional

  • Examines people of different groups at the same time. For example, studying people that are different ages at the same time to see what differences can be attributed to age

    • Quick and easy to conduct/generalizable results

    • Difficult to find a population that differs by only factor

    • Cannot measure changes over time

      • Research a large group of people with different backgrounds to get generalizable result 

• Longitudinal

  • same individuals are studied over a long period of time from years up to decades

    • More power than Cross-sectional

    • Require large amounts of time 

      • Study the same group of people for an extended period of time

• Midbrain: 

  • Responsible for eye movement, light reflex, control of sleep, wakefulness, and alertness

• Pons:

  • Bridge-like structure, helps with movement coordination and reflexes in swallowing and coughing 

• Medulla:

  • Lower part of the brainstem

    • Responsible for regulating vital body functions, including heart rate, blood pressure, and breathing 

• Frontal Lobe

  • Deals with problem-solving, decision making, planning, and judgement 

• Parietal Lobe

  • Receives input about touch, temperature, pain, and body position 

• Temporal Lobe

  • Auditory information and is involved in memory formation 

• Occipital Lobe

  • Visual information

Hypothalamus

• Deals with maintaining our body’s homeostasis and reward systems

  • Control center 

    • Regulate a wide range of bodily functions, including body temperature, thirst, hunger, and fatigue 

      • With the pituitary gland---->> Makes it responsible for controlling the body’s endocrine system

        • Which produces the hormones that regulate mood and energy levels

• Acetylcholine

  • Key role in muscle contraction and heart rate regulation

    • Involved in memory formation and learning

• Dopamine

  • Associated with pleasure and reward 

    • Often linked with addiction 

• Serotonin

  • Helps regulate mood, appetite, sleep, and some cognitive functions including memory and learning 

Plasticity: Although specific regions of the brain are associated with specific functions, if one region is damaged, the brain can reorganize to take over its function.

Glial cells guide the growth of developing neurons, help provide nutrition for and get rid of wastes of neurons, and form an insulating sheath around neurons that speeds conduction.

The neuron is the basic unit of structure and function of your nervous system.

The cell body (a.k.a. cyton or soma) contains cytoplasm and the nucleus, which directs synthesis of such substances as neurotransmitters.

The dendrites are branching tubular processes capable of receiving information.

The axon emerges from the cyton as a single conducting fiber (longer than a dendrite) that branches and ends in tips called terminal buttons, axon terminals, or synaptic knobs.

The axon is usually covered by an insulating myelin sheath (formed by glial cells).

Neurogenesis, the growth of new neurons, takes place throughout life.

Neurotransmitters are chemicals stored in structures of the terminal buttons called synaptic vesicles.

Dopamine stimulates the hypothalamus to synthesize hormones and affects alertness and movement.

Glutamate is a major excitatory neurotransmitter involved in information processing throughout the cortex and especially memory formation in the hippocampus.

Serotonin is associated with sexual activity, concentration and attention, moods, and emotions.

Opioid peptides such as endorphins are often considered the brain’s own painkillers. Gamma-aminobutyric acid (GABA) inhibits firing of neurons.

Norepinephrine, also known as noradrenaline, is associated with attentiveness, sleeping, dreaming, and learning.

Agonists may mimic a neurotransmitter and bind to its receptor site to produce the effect of the neurotransmitter.

Antagonists block a receptor site, inhibiting the effect of the neurotransmitter or agonist.

The neuron’s resting potential results from the selective permeability of its membrane and the presence of electrically charged particles called ions near the inside and outside surfaces of the membrane in different concentrations.

When sufficiently stimulated (to threshold), a net flow of sodium ions into the cell causes a rapid change in potential across the membrane, known as the action potential.

Circadian rhythm:

• Internal clock/biological clock: Controlling our temperature and wakefulness in 25-hour cycles

Psychoactive drugs:

• Substances that cause changes in the normal activities of the central nervous system

  • Disrupts the action of neurotransmitters and the communication between neurons in the brain

    • Affects mental processes such as perception, consciousness, cognition or mood/emotions 

      • Alcohol, caffeine, nictione, marijuna, LSD, heroin, amphetamines, and THC

Somnambulism

• Sleepwalking/Occurs during SWS

• Nightmares

  • Frightening dreams that wake a sleeper from REM

• Night Terrors

  • Sudden arousal from sleep with intense fear accompanied by physiological reactions

    • Rapid heart rate, perspiration that occur during SWS(SLOW WAVE SLEEP/Deep sleep)

• Narcolepsy

  • Overpowering urge to fall asleep that may occur while talking or standing up

• Sleep apnea

  • Failure to breathe when asleep

Sleep spindles:

• Bursts of neural activity that take place in stage 2 of NREM sleep and may be important for memory consolidation

  • Normal part of STAGE 2 NREM sleep 

    • Bursts of brain activity that show up when the brain is generally quiet and then a lil bit of active and then back to quiet

      • Tend not to be present in schizophrenics, alcoholics, and sociopaths/psychopaths

Selective attention:

• Our ability to focus on one particular task or stimulus among many competing stimuli

Cocktail party effect:

•  The ability to focus one's auditory attention on a particular stimulus while filtering out a range of other stimuli

  • Like when a person can focus on a single conversation in a noisy room

The nature-nurture controversy deals with the extent to which heredity and the environment each influence behavior.

Evolutionary psychologists study how natural selection favored behaviors that contributed to survival and the spread of our ancestors’ genes and may currently contribute to our survival into the next generations.

Behavioral geneticists study the role played by our genes and our environment in mental ability, emotional stability, temperament, personality, interests, and so forth; they look at the causes of our individual differences.

Identical twins are two individuals who share all of the same genes/heredity because they develop from the same fertilized egg or zygote; they are monozygotic twins.

Fraternal twins are siblings that share about half of the same genes because they develop from two different fertilized eggs or zygotes; they are dizygotic twins.

Heritability is the proportion of variation among individuals in a population that is due to genetic causes.

Turner syndrome have only one X sex chromosome (XO).

Klinefelter’s syndrome arise from an XXY zygote. Males with Klinefelter’s tend to be passive.

The presence of three copies of chromosome 21 results in the expression of Down syndrome.

The genetic makeup for a trait of an individual is called its genotype.

The expression of the genes is called its phenotype.

If the genes are different, the expressed gene is called the dominant gene; the hidden gene is the recessive gene.

Tay-Sachs syndrome produces progressive loss of nervous function and death in a baby.

Albinism arises from a failure to synthesize or store pigment and also involves abnormal nerve pathways to the brain, resulting in quivering eyes and the inability to perceive depth or three-dimensionality with both eyes.

Phenylketonuria (PKU) results in severe, irreversible brain damage unless the baby is fed a special diet low in phenylalanine within 30 days of birth; the infant lacks an enzyme to process this amino acid, which can build up and poison cells of the nervous system.

Huntington’s disease is an example of a dominant gene defect that involves degeneration of the nervous system.

Latent Content: Underlying meaning of a dream

Manifest Content: Remembered story line of a dream

Narcotics are analgesics (pain reducers) that work by depressing the central nervous system. They can also depress the respiratory system.

Stimulants are psychoactive drugs that activate motivational centers and reduce activity in inhibitory centers of the central nervous system by increasing activity of serotonin, dopamine, and norepinephrine neurotransmitter systems.

Hallucinogens, also called psychedelics, are a diverse group of psychoactive drugs that alter moods, distort perceptions, and evoke sensory images in the absence of sensory input.

Sensory or afferent neurons transmit impulses from your sensory receptors to the spinal cord or brain.

Interneurons, located entirely within your brain and spinal cord, intervene between sensory and motor neurons.

Motor or efferent neurons transmit impulses from your sensory or interneurons to muscle cells that contract or gland cells that secrete.

Paul Broca (1861) performed an autopsy on the brain of a patient, who had lost the capacity to speak, although his mouth and his vocal cords weren’t damaged and he could still understand language. Tan’s brain showed deterioration of part of the frontal lobe of the left cerebral hemisphere

• This connected destruction of the part of the left frontal lobe known as Broca’s area to loss of the ability to speak, known as expressive aphasia.

Carl Wernicke found another brain area involved in understanding language in the left temporal lobe.

Destruction of Wernicke’s area results in loss of the ability to comprehend written and spoken language, known as receptive aphasia.

Lesions: precise destruction of brain tissue, enabled more systematic study of the loss of function resulting from surgical removal (also called ablation), cutting of neural connections, or destruction by chemical applications.

Studies by Roger Sperry of patients with these “split brains” have revealed that the left and right hemispheres do not perform exactly the same functions (brain lateralization) that the hemispheres specialize in.

In magnetic resonance imaging (MRI), a magnetic field and pulses of radio waves cause the emission of faint radio frequency signals that depend upon the density of the tissue.

An EEG (electroencephalogram) is an amplified tracing of brain activity produced when electrodes positioned over the scalp transmit signals about the brain’s electrical activity (“brain waves”) to an electroencephalograph machine.

Positron emission tomography (PET) produces color computer graphics that depend on the amount of metabolic activity in the imaged brain region.

Functional MRI (fMRI) shows the brain at work at higher resolution than the PET scanner. Changes in oxygen in the blood of an active brain area alters its magnetic qualities, which is recorded by the fMRI scanner.

Central nervous system: consists of your brain and your spinal cord.

Peripheral nervous system : includes two major subdivisions: your somatic nervous system and your autonomic nervous system.

• lies outside the midline portion of your nervous system carrying sensory information to and motor information away from your central nervous system via spinal and cranial nerves.

Somatic nervous system: has motor neurons that stimulate skeletal (voluntary) muscle.

Autonomic nervous system: has motor neurons that stimulate smooth (involuntary) and heart muscle.

Sympathetic stimulation results in responses that help your body deal with stressful events including dilation of your pupils, release of glucose from your liver, dilation of bronchi, inhibition of digestive functions, acceleration of heart rate, secretion of adrenaline from your adrenal glands, acceleration of breathing rate, and inhibition of secretion of your tear glands.

Parasympathetic stimulation calms your body following sympathetic stimulation by restoring digestive processes (salivation, peristalsis, enzyme secretion), returning pupils to normal pupil size, stimulating tear glands, and restoring normal bladder contractions.

Spinal cord: protected by membranes called meninges and your spinal column of bony vertebrae, starts at the base of your back and extends upward to the base of your skull where it joins your brain.

Association areas are regions of the cerebral cortex that do not have specific sensory or motor functions but are involved in higher mental functions, such as thinking, planning, remembering, and communicating.

Medulla oblongata—regulates heart rhythm, blood flow, breathing rate, digestion, vomiting.

Pons—includes portion of reticular activating system or reticular formation critical for arousal and wakefulness; sends information to and from medulla, cerebellum, and cerebral cortex.

Cerebellum—controls posture, equilibrium, and movement.

Basal ganglia—regulates initiation of movements, balance, eye movements, and posture, and functions in processing of implicit memories.

Thalamus—relays visual, auditory, taste, and somatosensory information to/from appropriate areas of cerebral cortex.

Hypothalamus—controls feeding behavior, drinking behavior, body temperature, sexual behavior, threshold for rage behavior, activation of the sympathetic and parasympathetic systems, and secretion of hormones of the pituitary.

Hippocampus—enables formation of new long-term memories.

Cerebral cortex—center for higher-order processes such as thinking, planning, judgment;

receives and processes sensory information and directs movement.