PSY100 Final UofT

Lev Vgotsky Cognitive Development (zone of proximal development and scaffolding)

More emphasis on sociocultural factors

Zone of proximal development: Things learner can do with help as opposed to doing on their own or cannot do

Scaffolding: Gradually developing competence in a subject, learners can be helped to move beyond current developmental level

False-belief task (TofM)

Someone places an object down and leaves, the object is moved and the person returns. Where will the person look for the object

If no TofM child will say they’ll look in the new location

If TofM child will say they’ll look in the old location

Theory of Mind

Child can disregard own knowledge and acknowledge a different kind of knowledge (usually by age 5)

Egocentrism

Inability to think that other people’s views of the world exist

Piaget’s Cognitive Development 4 Stages

• Sensorimotor stage (0-2 years): acquiring information only through the senses, object permanence

  • primary circular reactions: infant interactions with own body

  • Secondary circular reactions: repetition of actions involving external object

  • Tertiary circular reactions: children adapt tactics to surroundings

• Preoperational Stage (2-6 years): Begin to think symbolically, he believed that they lacked understanding law of conservation

• Concrete Operational Stage (6-11 years): Develop more logical thinking, but limited to concrete objects

• Formal Operational Stage (12+ years): Able to think and reason abstractly, deductive reasoning and problem solving

Jean Piaget Cognitive Development (assimilation, accommodation, equilibration)

During each stage of development, children form schemas (ways of perceiving, organising, and thinking about how the world works)

Assimilation: incorporating new information into existing schema

Accommodation: modifying existing schemas or creating new ones to fit new information

Equilibration: balancing assimilation and accommodation so our cognitive structures match reality

Eric Erikson’s Psychosocial Model

Lifespan theory of development

Trust vs Mistrust (birth to 2 years)

Identity vs Role Confusion (adolescence)

Intimacy vs Isolation (early adulthood)

4 Types of parenting styles

Mary Ainsworth’s “Strange Situation” Test

Secure attachment, insecure-resistant, insecure-avoidant, disorganised attachment

Secure attachment: upset when caregiver leaves, comforted upon return

Insecure-resistant (anxious-ambivalent): clings to caregiver, gets upset, wants and resists comfort

Insecure-avoidant: little distress when caregiver leaves, avoids caregiver upon return

Disorganised attachment: inconsistent, odd behaviours

Harry Harlow Experiment

Cloth mother vs wire milk mother

Monkey preferred cloth mother but went to wire mother for milk

Attachment Theory

Emotional bond with caregivers early in life, it’s adaptive which means it encourages proximity between child and caregiver, oxytocin plays an important role

What are the brain development trends with blooming and pruning

Synapse formation till age two, then pruning, then second period of overproduction in the prefrontal cortex just before adolescence followed by about a decade of pruning

Signal Detection Theory

Common research techniques for determining what infants know (there’s two)

Preferential looking technique: if baby prefers one stimulus it has a preference

Habituation/Orienting reflex: something new is presented to us we orient to it

Windows of plasticity

Sensory, then motor/language, then higher cognition

Reflexes present at birth

Grasping, rooting, sucking

Auditory Transmission Steps

Outer Ear (pinna, tympanic membrane), Middle ear (middle ear bones, oval window), Inner ear (cochlea, basilar membrane (pitch)), auditory nerve, medulla (bottom most part of brain, controls vital processes like heartbeat and blood pressure), midbrain, thalamus, primary auditory cortex

Parts of the Eye

Fusiform Face Area (FFA)

Particularly active when people look at faces

Interpreter

Left-hemisphere process that attempts to make sense out of events (remember left-hemisphere is responsible for language)

Lateralization of Function

Localisation of a function in right or left hemisphere

E.g, language in the left

Motion parallax

Objects that are further away seem to move slower than objects that are closer

Muller Lyer Illusion

Lines might look different in length when in reality they’re the same length

Monocular depth cues

Occlusion, relative size, familiar size, linear perspective, texture gradient, and position relative to horizon

Binocular depth cues (Retinal Disparity)

For depth perception, caused by distance between the eyes and comparing disparity between two retinal images

6 Gestalt Principles

Figure Ground

Illusory contours: we perceive contours even when the don’t exist

Objects close together are grouped together (proximity)

Points that form smooth lines when connected belong together (continuity)

Seeing a complete unbroken image even when there’s gaps (closure)

We group figures together that resemble each other (similarity)

Agnosia

Inability to recognise and name objects, but can still use them

Ventral vs Doral stream

Ventral: perception of information about objects (“what”)

Dorsal: perception of spatial location and other information needed for action (“why”)

What happens when certain motion sensitive neurons are fatigued

Motion after-effects (waterfall illusion)

Opponent-process theory

Focus on ganglion cells, three opposing pairs (if one Color pair is stimulated, other is inhibited)

Red/Green, Yellow/Blue, White/Black

Trichromatic theory

Color perception determined by ratio of activity of 3 types of cones

3 types of cones

S cones (short wavelengths blue)

M cones (medium wavelengths green)

L cones (long wavelengths red)

Visual transmission steps

rods and cones -> bipolar, a machine, horizontal cells -> ganglion cells/optic nerve -> thalamus -> primary visual cortex

Cones

Color perception

Rods

Black and white perception

Photoreceptors

Convert photons to electrical signal (transduction)

Nociceptors

Responsible for sensing pain

Sensory homunculus

Representation of how much cortical space is devoted to each sense

Gate control theory of pain

For pain to be experienced pain must be activated the neural “gate” in the spinal chord must be open

Two different types of fibres in pain reception

Myelinated (“A delta”) fibres: sharp immediate pain

Non-myelinated (“C”) fibres: dull steady pain

primary somatosensory cortex

Connected parts of the body tend to be represented beside each other (somatotropin organisation)

More sensitive regions have more cortical areas devoted to them

Contralateral organisation

Left hemisphere processes right sensations and vice versa

Somatosensory cortex

Processes pain (in the parietal lobe), touch, pressure, temperature, position, movement and vibration

Mechanoreceptors

Respond to mechanical distortion or pressure, most sensitive in the cochlea for sound transduction

Vestibular system

In the inner ear, responsible for body position and movement

Where are olfactory receptors located

Olfactory epithelium (mucosa), thin layer of tissues embedded with smell receptors which transmit information to olfactory bulb and then the olfactory cortex

Where are taste receptors located?

Taste buds

Signal-detection (2 step process)

Intensity of stimulus

Individual observer’s criteria for deciding whether stimulus occurred

Psychophysics

Studying relationship between stimuli (physics) and perception of stimuli (psyche/mind)

Bottom-up processing

Incoming signals construct perceptions

Top-down processing

Knowledge from prior experience used to perceive stimulus

Sensory adaptation

Reduced response to unchanging stimulus

Difference threshold

Noticeable difference between two stimuli (minimum amount of change required for a person to detect a difference 50% of the time)

Absolute threshold

Minimum intensity of stimulus that must occur before you experience sensation

Synesthesia

Stimulation of one pathway = simultaneous stimulation of another pathway

Transduction

Translation from stimulus to neural signal

Perception

Involves processing and interpreting sensory signals resulting in internal representation of stimuli and conscious experience of it

Sensation

Detection of external stimuli, responses to those stimuli, and transmission of responses to the brain

Prefrontal cortex

Attention, regulation, memory processing, response inhibition

Orbitofrontal cortex

Emotion, antisocial personality disorder, receives info for senses (except touch)

Nucleus accumbens

Important for brain’s reward system, motivation, emotion, addiction, memory, learning, release dopamine

Neurogenesis

Creation of new neurons (hippocampus and olfactory bulb), contributes to plasticity

Glia

Supporting cells, provide structural matrix, clean up debris, form myelin sheath, holds neurons in place, reflexes, body functions (e.g, heart rate), blood-brain barrier

Executive Functions

Set of mental skills that help people manage information, make decisions and plan ahead

Include working memory, cognitive flexibility, inhibitory control, self-awareness, emotional regulation, motivational regulation

cingulate cortex

Part of the limbic system, processes pain, empathy, impulse control, motivation and decision making

HPA axis

Hormone system that helps the body manage stress and maintain homeostasis

Example of plasticity and rats

Enriched rats had more synapses and neural connections

Impoverished rats had less

Is the nervous or endocrine system slower

Endocrine

Coordinated system process in the endocrine system

Hypothalamus secretary’s releasing factor which causes pituitary gland to release a hormone specific to that factor. Hormone travels through bloodstream to target sites

What neurons does the somatic system use primarily

Motor neurons (efferent)

Sometimes use sensory neurons

Peripheral Nervous System

Transmits info to the CNS and responds to messages from CNS to perform certain behaviours or make bodily adjustments

• somatic and autonomic

Cerebral cortex lobes

Occipital (primary visual cortex)

Parietal (primary sensory cortex)

Temporal (primary auditory cortex)

Frontal (primary motor cortex)

Corpus Callosum

Connects hemispheres and allows info to flow between

Cerebral cortex

Outer layer of brain, each hemisphere has four lobes

Limbic System

Hippocampus: formation and storage of long-term memory and amygdala: processing fear, essential to our ability to associate things with emotional responses

Basal Ganglia

Motor control

Diencephalon: thalamus and hypothalamus

Hypothalamus: regulatory structure -> nervous system to endocrine (4 Fs)

Thalamus: relay station, sensory information except smell

Cerebellum

Coordinated movement and balance

Reticular formation

Alertness, sleep

Brainstem

Controls functions of the autonomic nervous system including breathing digestion, heartbeat, etc.

Neuroplasticity

Brain is plastic

Agonist vs antagonist

Agonist: bind to receptors and mimics neurotransmitter, or increasing release of neurotransmitters, blocking re-uptake of neurotransmitters

Antagonist: inhibiting action of neurotransmitter by blocking release, destroying neurotransmitters, mimicking neurotransmitter and blocking binding

Epineprine & norepinephrine

Stress response, fight or flight

Acetycholine

Movement; memory, cognition, sleep

Dopamine

Reward and motivation, voluntary movement

Serotonin

Mood, impulsiveness, hunger, sleep

GABA

Primary inhibitory neurotransmitter

Glutamate

Primary excitatory neurotransmitter (GO)

Presynaptic membrane vs postsynaptic membrane

Presynaptic: membrane of the neuron that is sending the signal

Postsynaptic: membrane of the neuron that is receiving the signal

All-or-None Principle

A neuron fires with the same magnitude each time, frequency can vary

Excitatory vs Inhibitory signals

Excitatory: increase likelihood of neuron firing

Inhibitory: decrease likelihood of neuron firing

Action potential process

Positive in the nodes of ravenier, negative at the myelin sheaths

Parts of a Neuron

Neuron Types

Sensory (afferent): to the brain

Motor (efferent): exit the brain

Interneurons (between afferent and efferent)

PNS and its components

Peripheral Nervous System

• Somatic Nervous System (conscious)

• Autonomic Nervous System (unconscious)

  • Sympathetic Nervous System: system on alert

  • Parasympathetic Nervous System: relax systems

CNS and its components

Central Nervous System

Brain and Spinal chord

Heredity vs Heritability

Heredity: Genetic transmission of characteristics from parents to offspring

Heritability: estimate of the genetic proportion of the variation in some specific traits (within a population)

• Estimate of heritability: % of variation that is explained by genetic differences

Epigenetics

Changes in gene expression due to non-genetic influences

Francis Galton

Eugenics guy

Reproducibility vs Replicability

Reproducibility: study can be duplicated in method and/or analysis

Replicability: study about phenomenon produces similar results from previous study of same phenomenon

• close/exact: trying to recreate original study

• Conceptual: test same underlying hypothesis or theory, may use different methods