Psychology 1XX3 Development, Evolution, Neuroscience, Vision

What is development

Changes that occur in a lifetime

Maturation

Biologically-timed unfolding of changes according to a genetic plan

Learning

Storing of new information that is processed to become automatic (Ex. look both ways before you cross)

Interactionist perspective

Interactions between maturation and learning = development, biological maturation restricts the timeline of learning

4 methods of measuring abilities in infants

Habituation, Event-related potentials, High-amplitude sucking method, Preference method

Habituation goal

Determines if an infant can detect the difference between 2 stimuli

Habituation

A decrease in responsiveness to a stimulus following its repeated presentation

Dishabituation

An increase in responsiveness to a stimulus that is different from the habituated stimulus, indicates ability to perceive different stimuli (Ex. Test colour perception)

Habituation procedure

Tests ability to differentiate between stimuli, repeatedly present same stimulus and measure any physiological changes (ex. heart rate), overtime infants become habituated to stimulus and physiological changes return to resting state

Event-related potentials

Measure of the brain’s electrical activity via special cap with array of electrodes that detects changes in neuron activity in specific areas of the brain to indicate response to certain stimuli (Ex. Auditory stimuli = Temporal region activity)

High-amplitude sucking method

Measured by pacifier, baseline sucking level is measured and stimulus is presented, if infant likes stimulus, it will increase rapidity to continue presentation of stimulus, and lack of sucking indicated lack of preference

Preference method

Measures preference between stimuli, compares level of visual attention given to each stimuli to observe preference, longer = likey

Competence-performance distinction

An infant may fail tests due to inability to perform actions, not because they lack the cognitive ability, cannot assume results correlate with actions

Developmental studies

Study developmental changes over lifetime, longitudinal and cross-sectional

Longitudinal design

Examines same individuals repeatedly over their lifetime, expensive and time-consuming, unreliable (death) practice effect bias (improvement on exposure-basis rather than developmental-basis)

Cross-sectional design

Test different individuals of different age-groups at once, faster comparison, cannot distinguish between generational effects and natural development, does not directly track changes with age

Canalization principle

Genotype restricts the phenotype to a small # of possibilities (Ex. all infants babble despite coming from different language backgrounds), we all share basic phenotypic traits despite environment influences

Range-of-reaction principle

Genotype establishes a range of possible phenotypes in response to different life experiences

Canalization

Restricts upper and lower bound phenotype of trait based on species (Ex. 4ft - 6ft), for general population, based on gene pool

ROR

Establishes your personal expression of a trait based on your individual environment

How do genes influence your environment

Passive, evocative, active

Passive genotype correlations

Influences most in early life, your parent’s choice of environment was influenced by their own genes, and will thus complement yours

Evocative genotype correlations

Influence most throughout lifespan, inherited traits impact how others react and behave towards you (Ex. difficult temperament, others may think you’re annoying(

Active genotype correlations

Genotype influences the kinds of environments you seek

Critical period

Specific time in development in which stimulation is necessary to see permanent changes in specific abilities (Ex. vision), after this, same stimulation will not illicit same benefit (ex. deprivation outside cp has no consequence), more stimulation ≠ better development

Types of brain development

Experience-expectant & experience-dependent

Experience-expectant brain growth

The brain expects a certain amount of environmental stimuli in which it develops normally

Experience-dependent brain growth

The brain develops according to personal experiences, recflects the subtle developments in strucuture

Sensitive periods

Critical periods except learning may still occur post-period, flexibility in timings and type of stimulation for normal development

Biological exuberance

Infants produce trillions more synapses than found in the adult brain

The Mozart effect

The enhancing effect of music is only temporary

Marshmellow experiment

As we develop, we gain the ability to delay immediate gratification, low restraint = 1 marshmallow now, high restraint = 2 later

Adaptations

Biological traits that help an individual get better suited to their environment to survive and reproduce, includes mental functions (Ex. memory retrieval), arise due to pressures of natural selection

Evolution

Change in gene frequencies

Stabilizing selection

Selection consistent with the average trait

Sexual selection

Female mating preferences, physical appearance contributes to fitness

Inter-sexual selection con

Physical appearance may increase males chance of successful mating, but may decrease their chance of survival (Ex. peacock feathers)

Inter-sexual selection

Female choice (attractiveness), anatomical traits differ between sexes

Intra-sexual selection

Male competition, exists mostly during breeding season

Species-specific behaviour

Behaviour is an evolved trait that distinguishes species (Ex. Movement, habitat, social system)

Altruism

Negative effect on actor, positive effect on recipient

4 types of social behaviour

Cooperation, altruism, selfish, spite

Cooperation

Positive effect on both actor and recipient, increase in group success maximizes chances of overall success (Ex. Geese foraging in groups increases personal success of obtaining food as others scan for predators)

Selfish

Positive effect on actor, negative effect on recipient

Spite

Negative effect on both actor and recipient

Eusocial Hymenoptera

Level of social organization, individuals spend their lives serving the colony without reproducing, run by relatedness, genes can be successful and altruistic if they helped identical copies of themselves

Selfish gene

Natural selection favours the selfish gene that best serves own interest, altruism = decrease of fitness, selfish = increase of fitness

Cost vs benefit

Interaction of social behaviours (Ex. you help out someone even if it doesnt benefit you, but itll benefit the group)

Lemons and evolution of altruism

Kill themselves if overpopulation occurs to allow for more nutrients, but altruistic lemon genes die with these lemons, and selfish lemons reproduce, does not explain evolution of altruism

Types of fitness

Direct and indirect

Direct fitness

Genes passed through personal reproduction

Indirect fitness

Genes passed through genetic relatives reproduction

Inclusive fitness

Direct + Indirect fitness

Hamilton’s Rule

Predicts when altruistic behaviours are favoured (when rB > c)

c = reproductive cost to actor

B = reproductive benefit to recipient

r = degree of relatedness between actor and recipient

Relatedness

Probability that actor and recipient share genes

Hamilton’s rule relatedness degree

Full sibling = 0.5

Parent = 0.5

Half sibling = 0.25

Uncle/Aunt = 0.25

Hamilton’s rule example

Sacrifice yourself to save 3 brothers = rB > c, altruism will triumph

c = 1

B = 3

R = 0.5

Cinderella effect

Step-siblings suffer increased abuse when compared to direct offspring

Aggression and relatedness

Aggression increases as relatedness decreases (Ex. In-laws)

Cues of kin recognition

Mother’s association, phenotype matching, co-residence with siblings

Dispersal and kinship

Those who do not disperse from kin are more likely to act altruistically for kin than those who disperse (Ex. female ground squirrels)

Direct reciprocity

Individuals help each other and both benefit

Phenotype matching

Increased prosocial behaviour towards those who resemble us, evaluation of relatedness based on phenotypic similarity

Indirect reciprocity

Individuals help others who have helped others, establish good rep by helping so others will want to help as well

Outcome variance

Leads to sex-differences in risk-taking tolerance, males generally exhibit higher outcome variance than women

Sex and adaptive problems

1. Metabolic demands of reproduction, higher strain on women

2. Parental investment, women investing more resources in are more selective in mate choice, while the lesser-investing sex competes for mating opportunities

3. Genetic cuckoldry, when a male unknowingly invests resources in offspring that are not genetically his own, having been deceived by a female's infidelity

Renée Descartes

The mind is a separate entity in control of our actions and thoughts, physical vs mental

Neuron

Specialized communication cells

Absolute Refractory Period

Begins when action potential is initiated and ends when membrane potential dips below threshold, a neuron is completely incapable of firing a second action potential, no matter how strong the stimulus is

Relative Reactive Period

Lasts until resting potential is re-established, Na+ channels open to allow 2nd action potential to occur if stimulus is strong enough to overcome undershoot making it harder to initiate a new action potential

Temporal summation

High frequency stimulation by 1 pre-synaptic neuron

Spatial summation

Simultaneous stimulation by several pre-synaptic neurons

Spatio-temporal summation

Temporal + spatial summation occur at the same time, used if temporal/spatial alone may not be enough to translate proper degree of pain

Regulatory channels

Leaky K channel, Voltage-gated channel, Ligand-gated channel, Sodium channel, Potassium channel

Neural development

Begins 18 days after conception, Neural plate folds to form neural tube where the brain and spinal cord connect

Ventricular zone

Cells begin dividing asymmetrically to produce glial cells and neurons

Neuron migration

Neurons migrate from ventricular zone to cortical surface by using radial glial cells as ‘ropes’

Dualist Framework

Mind and brain are separate, mind is outside of the body but controls actions

Receptive parts of neurons

Dendrites and cell body

Dendrite function

Connects to end of other neuron to relay info

Cell body function

Carries genetic info, maintains structure, provides energy

Trasmissive parts of neuron

Axon & axon terminal

Axon terminal

Contains terminal boutons, connect with others on other neurons

2 types of potassium channels

Leak and Voltage-gated Potassium channel

Leaky K Channel

Allows K+ to exit neuron, maintains resting potential

Voltage-Gated potassium channel

Closed in resting state, +Na enters in low concentration

Action potential

Fundamental unit of communication for neurons

Dorsal

Back

Ventral

Front

Human standing orientation

Rostral = Top of head

Ventral = In front of head

Dorsal = Back

Caudal = Below head

Brain orientation (account for tilt)

Dorsal = Top

Ventral = Bottom

Rostral = In front of

Caudal = Back

Medial

Towards inside of brain

Lateral

Towards outside of brain

What did Phineas Gage’s case support

The brain has specialized sides for specific behaviour

Microelectrodes

Used to electrically stimulate areas of the brain and observe behaviour to build anatomical maps of the brain

Single cell recording

Small electrode inserted into nervous tissue and neural activity is recorded, pattern of firing reveals particular neurons functional role

CT scan

Non-invasive, produces X-ray slices of the brain, low resolution, difficult to examine but helpful to diagnose brain injuries

MRI

Non-invasive, magnetic field localizes tissue to create detailed map of soft tissues, expensive and long,

PET Scan

Invasive, radioactive tracer (ex. glucose) is ingested and tracked to measure metabolic activity, tracks brain function related to cognitive tasks

fMRI

Non-invasive, detects changes in blood oxygen levels and identifies active brain regions during specific tasks, bad for precise timing (oxygen spike more delayed than functional activity of the brain)