better psych237 exam 1

cognitive psychology

study of the mind and mental processes

Donders (1868)

• reaction time & mental processes

• included simple reaction time (single stimuli with either the presence of absence of it, pressed a button in response) and choice reaction time (2+ stimuli and a specific button was to be pressed based on what light came on)

• Model: Stimulus → mental response → behavioral response

Wundt (1879)

• Structuralism

• Main method was analytical introspection (observers described their sensory experiences under controlled conditions in response to a stimulus)

• Flaw was that the results were subjective & difficult to replicate

Ebbinghaus (1885)

• Savings method

  • higher savings = greater memory

• Forgetting curve

  • most forgetting happens quickly and then tapers off

  • limitation was that he only tested it on himself

• Nonsense syllables to test

  • does not accurately represent how memory is used day-to-day

Watson (1920)

• Behaviorism

  • The only focus was on direct, observable behavior

• Rejected analytic introspection

  • Results varied widely

  • Focused on invisible inner processes that are hard to accurately test & prove

• Little Albert experiment

  • used classical conditioning

  • learned that emotional responses could be conditioned

Skinner (1930)

• Behaviorism

• Argued that children learn language through operant conditioning and imitation

  • Behavior is shaped by its consequences

• Skinner’s Box

  • animals (rats) press levers for food reward

Tolman (1930’s)

• Rats & maze

• Cognitive Map

  • evidence of latent learning & internal representation

  • Behaviorism cannot explain these behaviors

Chomsky (1959)

• Language is an innate process that children are born with

• argued that children produce sentences they have never heard, say incorrect things, and have never been rewarded

Digital Computer

• provided a metaphor for human cognition

• Model: Input → Processing → Output

  • Input: takes in information from the environment

  • Processing: processes the information internally

  • Output: produces a behavioral response

Cherry’s Attention Model (1953)

• dichotic listening studies demonstrated selective attention

• behaviorism could not explain this

Dartmouth & MIT Conference (1956)

cited as the start of cognitive science

Broadbent’s Flow Diagram (1958)

• modeled what happens when a person directs attention to one stimulus

• Model: Input → Filter → Detector → To Memory

Sensory Memory (Atkinson & Shriffin)

very brief storage that holds unprocessed sensory information for less than one second

• separate stores exist for different senses

  • Iconic = vision, echoic = hearing

Short Term Memory (Atkinson & Shiffrin)

holds a small amount of information for about 15-30 seconds without rehearsal

Long Term Memory (Atkinson & Shiffrin)

relatively permanent storage with a very large capacity

Tulving (1972)

broke down Atkinson & Shiffrin’s long-term memory into three main components

Episodic Memory

personal experiences and life events

Semantic Memory

facts and general knowledge

Procedural Memory

physical actions and skills

Nerve Net

early theory that suggested that the nervous system is like a connected highway system

Neuron Doctrine

• Ramon y Cajal

• contradicted nerve net

• suggested that the nervous system is made up of individual cells (neurons) and is NOT continuous

• signals are passed between synapses among the neurons

Golgi Staining Technique

technique developed to identify & label individual neurons

• supported the neuron doctrine

cell body

contains nucleus

dendrites

receive incoming signals

axon

carries signals outward to other neurons

receptors

specialized neurons that detect information from the environment

brain neurons

receive input from other neurons

action potential

electrical signal traveling down the axon

• based on the stimulus, the size stays the same but the firing rate changes

  • Weak stimulus → slow firing, strong stimulus → fast firing

• when action potential reaches the end of the axon, it releases neurotransmitters into the synapse, to then pass along the signal

frontal lobe

planning, decision-making, speech production

• contains motor cortex

parietal lobe

touch, tactile processing, spatial processing

• contains the somatosensory cortex

• dorsal (where/how) pathway!

temporal lobe

hearing, comprehension, object recognition

• contains the Fusiform Face Area (FFA)

• part of ventral (what) pathway!

occipital lobe

primary visual processing

• contains visual cortex

• starting point for both ventral & dorsal pathway

Broca’s Area

• left frontal lobe

• damage produces Broca’s aphasia

  • slow speech, effortful, and stripped down to content/simple words

  • comprehension is mostly intact

Wernicke’s Area

• posterior left hemisphere, where temporal and parietal lobes meet

• damage produces Wernicke’s aphasia

  • person can speak fluently, has normal grammar

  • words are jumbled

  • comprehension is very impaired

Double Dissociation

Broca’s and Wernicke’s Area are an example since they have opposing results when damaged

• proved that production and comprehension must rely on separate brain regions

fMRI

measures the BOLD (Blood-Oxygen-Level-Depedent) signal

• measures correlation and not causation

• activation for a task does not prove that the region is necessary for a task

Fusiform Face Area (FFA)

responds selectively to faces, damage can cause prosopagnosia ( an inability to recognize faces)

• can also respond to non-face categories after training, suggesting that it is an expertise-processing area

• Greebles

Parahippocampal Place Area (PPA)

responds selectively to scenes and places

Extrastriate Body Area (EBA)

responds selectively to images of bodies and body parts

perception

the experience resulting from stimulation of the senses

• perceptions can change based on added information

• perception involves a process similar to reasoning or problem-solving

Inverse Projection Problem

• distances, orientations, and sizes are all factors to interpretation

• objects can be blurred, hidden, or viewed from different angles

• the visual system overcomes this by using unconscious inference, Gestalt grouping,

Bottom-Up Processing

data-based

• general to specific

• starts with information hitting the senses, and builds upwards towards recognition, driven by the stimulus itself

Top-Down Processing

knowledge-based

• specific to general

• expectations, prior knowledge, context and past experience shape what we perceive

• works alongside bottom-up to resolve ambiguity

The Blob Figure

ambiguous black & white picture that once observer is told it is a Dalmation, prior knowledge helped to see the image clearly

• top-down context changes

Speech Segmentation

we hear continuous speech as separate words, even though the acoustic signal has no reliable pauses between them

• our knowledge of language fills the gaps

  • ex: vocabulary & transitional probabilities help out with that

Likelihood Principle

We perceive the world in the way that is “most likely” based on our past experiences

• We use knowledge to inform our perceptions and infer much of what we know about the world

Helmholtz’s Unconscious Inference

proposed that perception involves unconscious inferences

• the brain automatically uses prior knowledge to interpret sensory input without deliberate effort

Gestalt Principles of Perceptual Organization

this group of psychologists proposed that perception is determined by specific organizing principles that are built into the visual system

Proximity

elements near each other tend to be grouped together

Similarity

similar elements tend to be grouped together

Good Continuation

lines tend to be seen as following the smoothest path

Pragnanz (simplicity)

every stimulus pattern is seen as simply as possible

• example: Olympic rings seen as 5 circles, not 9 shapes

Common Fate

elements moving in the same direction are grouped

Common Region

elements within the same bounded area are grouped

Oblique Effect

horizontal & vertical orientations are more common than oblique angles in natural scenes

Light-From-Above Assumption

Because overhead light is most common, shadows provide depth and distance cues

Scene Schema

knowledge of what a given scene ordinarily contains

Bayesian Inference

provides a framework for how the brain combines prior knowledge with incoming sensory information

Prior Knowledge

Your initial expectation about what is likely to happen based on past experiences and context

• top-down component of Bayesian Inference

Likelihood

how well the current sensory evidence matches each possible interpretation

• bottom-up component of Bayesian Inference

Posterior

the updated belief that after combining the prior and the likelihood, this is the brain’s best guess about what is actually out there

Top-Down Processing Errors

• expectations are inaccurate

• context is misleading

• an example is when visual illusions produce percepts that do not align with physical reality

Experience-Dependent Plasticity & FFA

This idea has solidified the idea that the FFA is an expertise-processing area

• Greebles

• FFA seen activated with birds for bird experts, cars for car experts, and chess positions for chess experts

Ventral Pathway

the What pathway, perception pathway

• runs from occipital lobe to temporal lobe

• handles object identity and recognition

• temporal lobe lesions impair the object discrimination problem

Dorsal Pathway

the Where/How pathway, action pathway

• runs from occipital to parietal lobe

• handles spatial location and guides actions such as reaching or grasping

• parietal lobe lesions impair the landmark discrimination problem

Selective Attention

the ability to focus on one source of information while ignoring others

• Cocktail Party Effect

• Colin Cherry & Shadowing

Broadbent’s Filter Model (Early Selection)

All or Nothing filter

• sensory memory holds all informative information briefly, and a filter then selects one message based on physical characteristics (pitch, location, loudness) to then block everything else out

• cannot explain how people sometimes detect meaningful information in the unattended model

  • Cocktail party & name

Treisman’s Attenuation Model

Attenuator instead of all/nothing filter

• instead of blocking out, the attenuator turns them down

• each word has an activation threshold in a dictionary unit

  • One’s name has a low threshold

  • most words do need full attention to be recognized, meaning they have a high threshold

Lavie’s Perceptual Load Theory

proposed that whether distractors get processed depends on the perceptual load of the task

Low Load

the task is easy and does not use up all your attentional capacity

• leftover capacity automatically spills over and processes distractors

High Load

the task is demanding and uses up all available capacity

• there is nothing left over for distractors so they are effectively shut out

Voluntary Attention

• Top-down, goal directed attention

• the person consciously chooses where to direct attention based on their goals, interests, or the task’s requirements

Reflexive Attention

• bottom-up, stimulus driven attention

• attention is captured automatically by something salient, such as a loud noise, bright flash, or sudden motion

• this type of attention orients rapidly but fades quickly unless the stimulus is important

Competition between Voluntary & Reflexive

Appears when one is studying (using voluntary attention on the textbook) and your phone buzzes (reflexive attention by the notification)

100 Car Naturalistic Driving Study

noted that driver inattention was involved of ~80% of crashed and ~65% of near crashes

Inattentional Blindness

the failure to notice something plainly visible when your attention is occupied elsewhere

• gorilla experiment

Object Based Attention

attention can spread throughout an attended object

• attention is not strictly location-based; it can follow the boundaries of objects

Feature Integration Theory

Treisman proposed that perception occurs in 2 stages: preattentive and focused-attention

• mostly bottom-up processing but top-down can influence the focused attention stage when participants are told what to expect

Preattentive Stage

objects are automatically and rapidly broken down into individual factors, such as color, shape, and orientation.

• happens in parallel across the visual field without effort or awareness

Illusionary Conjunctions

when attention is overloaded, features from different objects can be mistakenly combined

• Ex: seeing a red circle and a blue square but perceiving a red square