Psyc/Soc MCAT

Biological approaches to behavior - OVERVIEW

Biological approaches to behavior - OVERVIEW

Approaches to behavior based on:

• Genes

• Hormones

• Neurotransmitters

Very fixed→ generally well-understood

Sociological approaches to behavior - OVERVIEW

Approaches to behavior based on:

• Social constructionism

• Symbolic interactionism

• Functionalism

• Conflict theory

Psychological approaches to behavior - OVERVIEW

Approaches to behavior based on:

• emotions

• attitudes

• memories

• cognition

• personality

More wiggle room→ still left to be discovered

Ekman’s List of Universal Emotions - OVERVIEW

• Happiness

• Feart

• Disgust

• Anger

• Sadness

• Contempt

• Surprise

Sociological approaches to experimental design - OVERVIEW

• difficult to manipulate experimentally

• emphasis on retrospective study

• cross-sectional study

• qualitative research designs

Genetics in development - OVERVIEW

• instinctual behaviors must be gene-based

Cultural learning

behaviors learned through culture

adaptive traits

traits that promote reproductive success of an organism

temperament

how an individual responds behaviorally and emotionally from stimuli

environmental factors

non-genetic influences

• stress

• endocrine-disrupting compounds

• observations of others

heritability

• degree of variation in a trait due to variation in the genotype

• number quantifyign the impact of genetic over environmental variation on a trait

study design for heritability

• twin studies → share DNA

• adoption studies → studies genes and environment

epigenetics

changes to the genome that do not involve changing the primary sequences

methylation

adds a methyl group to an amino acid (generally cytosine) that silences gene expression

• can happen from environmental stimuli

human physiological development - pregnancy

12 weeks

• organ systems formed

• umbillical cord connects to placenta

• 3 trimesters

  • 1: major structures formed

  • 2: smaller features added, growth

  • 3: growth + prep for birth

placenta

• vascular tissue bed

• fetal and maternal circulation are connected

• exchange nutrients, gases, waste

• maternal malnutrition/smoking/drug use can impact baby

• stress can impact baby

Palmar grasp reflex

automatic grasp of object when palm is stroked

rooting reflex

baby will search for an object that brushes against cheek

sucking reflex

baby will suck when something touches top of mouth

Moro reflex

startle reflex → sudden movement/loud sounds

Babinski reflex

stroking of bottom of foot causes toes to fan out and up

Developmental stages 0-12mo

motor: walking, standing with assistance, crawling

social: stranger anxiety, object permanence

linguistic: laughing, babbling, easy words

Developmental stages 12-24 mo

motor: walking, climbing, drawing, throwing

social: sense of self, boundaries (“no!”)

linguistic: word explosion, pronouns

Developmental stages 3+ yo

motor: more complex/mature behavior, toilet training, drawing recognizable objects

social: taking turns, gender awareness, playing with others, manipulating behaviors

linguistic: complex sentences, active vocab (used words) + passive vocab (understood words)

critical period

time when experiences imprint with life-long effects

• language: early language learning is essential for later communication

• sensory perception

• relationship-building

Adolescence (generally 13-19)

transition from childhood to adulthood

• broad term, including cognitive, social, behavioral changes

  • can vary culturally

puberty- start

menarchy/first period- start of puberty in women

first ejaculation - start of puberty in men

• varies based on environmental factors/culturally

puberty - sex characteristcs + hormones

men (Testosterone): pubic hair, facial hair, adams apple, more muscle

women (estradiol) : pubic hair, breasts, wider hips, fat distribution

Adulthood - developmental changes and behaviors

prefrontal cortex develops until ~25

• myelination of axons → signals transmit rapidly

• risk-taking behaviors

aging - biological, physical, mental impacts

• degradation of telomeres

  • limits how often a cell can divide

• gradual physical decline

  • prone to diseases

• mental:

  • decrease in fluid intelligence

  • decrease in mental processing speed

  • crystalized intelligence remains

classical conditioning - overview

• elaborates on the mechanism of conditioning/learning

Pavlov’s Dogs-classical conditioning

• paired sensory stimulus with another (meat and metronome)

• eventually, only metronome was associated with feeding

• shifts unconditioned response to conditioned one

unconditioned stimulus-classical conditioning

stimulus that activate a certain reaction, but has not been conditioned

unconditioned response-classical conditioning

a certain reaction, but has not been conditioned or associated with a stimulus

acquisition-classical conditioning

succesful conditioning

conditioned stimulus-classical conditioning

particular stimulus that has been intentionally reinforced to activate a certain reaction

conditioned response-classical conditioning

reaction associated with a particular stimulus that has been intentionally reinforced

neutral stimulus-classical conditioning

stimulus associated with any kind of reaction

conditioning-classical conditioning

transforms an unconditioned response to conditioned one

extinction-classical conditioning

loss of a conditioned response to a certain stimulus

habituation-classical conditioning

repeated stimuli elicit a diminished response over time

dishabituation-classical conditioning

intervening stimulus re-sensitizes the person to original stimulus

spontaneous recovery-classical conditioning

reemergence of conditioned response after extinction without another conditioning process → response tends to be less strong

stimulus generalization-classical conditioning

same conditioned response from a stimulus that is similar to, but not the same as, the original stimulus

stimulus discrimination-classical conditioning

ability to distinguish similar stimuli from each other

Operant conditioning - overview

• BF Skinner

• reward is key concept

• reinforcement vs punishment

reinforcement - operant conditioning

anything that increases the frequency of a behavior

punishment- operant conditioning

anything that decreases the frequency of a behavior

positive - operant conditioning

something is added

negative - operant conditioning

something is removed

positive reinforcement - operant conditioning

positive stimulus after a behavior we want to increase

negative reinforcement- operant conditioning

removing an unpleasant stimulus in a behavior we want to increase

positive punishment- operant conditioning

adding adversive stimulus to decrease behavior

negative punishment - operant conditioning

removing a pleasant stimulus to a behavior we want to decrease

escape learning - operant conditioning

learning a behavior to terminate an adversive stimulus (eg, turning off alarm clock)

avoidance learning - operant conditioning

behavior that’s intended to prevent adversive stimulus from happening

continuous reinforcement - operant conditioning

provide reinforcement every time target behavior is performed

partial reinforcement- operant conditioning

provide reimforcement just some of the time the target behavior is performed (on a ratio or time-based schedule)

fixed ratio- operant conditioning, example

eg, rat given a pellet every four times it pushed a lever

fixed interval- operant conditioning

reinforcement for behavior after a certain amount of scheduled time

variable ratio - operant conditioning, example

eg, rat gets a food pellet every 2-8 times it pushes a lever

variable interval- operant conditioning

reinforcement for behavior given after a random amount of time passes

which combination of fixed/variable and ratio/interval is most effective? - operant conditioning

variable ratio reinforcement

• fastest aquisition of behavior

• most resistant to extinction

Overlap between classical and operant conditioning

• take stimulus that is naturally associated with a reaction via biological programming

• associate primary stimulus with a secondary one that was originally neutral

• new stimulus becomes conditioned/secondary stimulus

shaping - operant conditioning

gradual approximations of a target behavior are rewarded

instinctive drift - operant conditioning

animals will revert back to biological behaviors unless reinforcement continues

(operant conditioning is overlaid on fundamental biological behaviors, choose behaviors that appeal to these for fast behavioral uptake)

latent learning - operant conditioning

subject learns something that is not the target of the experimental design (eg, rats run a maze without food, but can then run the maze faster when there is food involved)