Psych 240 Exam 1

Common misconception about study strategies

better performance = more learning

maximizing learning

training methods that’re most effective for long-term learning tend to introduce difficulties that make short-term performance worse

Simon Bjork Experiment

Evaluating strategies: criteria

1. does the technique work in a variety of environments?

2. does the technique work for a variety of different students?

3. does the technique work for different types of material?

4. is the technique effective regardless of how learning is tested?

highlighting

• may cause us to focus on osilated facts and ignore bigger connections

• students may struggle to distinguish central ideas from peripheral information

fowler & baker: highlighting didn’t help → when all 3 groups were tested on material a week later, they all performed about the same

peterson: on questions that covered basic factual material, all 3 groups performed the same; on questions that required students to draw inferences, students who underlined did worse

rereading

• doesn’t improve comprehension or performance on inference-based questions

• rereading a 2nd or 3rd time doesn’t help

• can give students the mistaken impression that they’ve mastered the material

rothkopf: more exposure to readings led to more correct responses for shorter worded passages and less correct responses for larger worded

geenrating explanations

• coming up with explanations for why concepts are true, or how they relate to what you already know

Presley et al: the group who generated their own explanations performed about twice as well as the other groups

interleaved practice

• mix up problems and jump back and forth from one topic to another

Rohrer & Taylor: blocked practice had better performance for practice but interleaved practice had better performance for test

distributed practice

• spreading out your study over time with breaks

bahrick: 30 day between sessions group had best test results and then 1 day between sessions group and then 0 days between sessions

testing yourself

• one of the single most effective ways to learn

butler: practice test group had better final test performance than restudy group

utility of study strategies

highlighing → low

rereading → low

generating questions → moderate

interleaving practice → moderate

distributed practice → high

testing → high

What is Cognitive Psychology?

scientific study of human mind

study of structures and processes of mind and brain that take in, transform, and use information

processes required

• perceive letters

• recognize words

• comprehend english setence

• access knowledge of objects

• decide truth or falsify

• remember true-left, false-right

• decide which chand to raise

• use movement processes to move hand

The problem

mind is unobservable

• stimulus → “black box” → response

some solutions: inrtospectionism, behaviorism, cognitivism

introspectionism

just look inside and see what is going on…

Wundt

Titchener

problems with introspection

difficult to verify

private events, not public

end product, not the process itself

Behaviorism

psychology is science of behavior

emphasis on what can be directly observed: stimuli; responses; reinforcements/rewards; rats in mazes

stimulus → no black box → response

• ignore the mind(unobservable)

pavlov

Watson

BF Skinner

Problems with behaviorism

can’t account for diversity of human behavior ex: language

limiting science to observable is a bad idea

cognitive approach

infer what’s going on inside the box

stimulus → brain in box → response

dependent variable

what you measure/analyze

• reaction time

• accuracy

• barin activity

independent variable

what you manipulate

• number of items to be memorized

• amount of alcohol ingested

• passage of time

Mental chronometry

invented by Donders

study of the time course of mental processes

Recognition test

higher study time had greater percentage of correct responses at 10mins, day 1 and day 10 compared to lower study time

reaction time methods

assume mind is info processing computer

lots going inside balck box

reaction time methods are a powerful approach

nformation processing stages

stimulus → processing → still more processing → response

each stage

• receives information from the previous stage

• transforms information

• sends information to the next stage

detection task

press button when you see red or green light

s → detection → r

choice task

press left button for red light; right button for green light

s → detection → decision → r

subtractive method

s → detection → decision → choice RT. 285 ms

s → detection → detection RT 197 ms

duration of decision stage = 88 ms

subtractive method: problems

1. assume of pure insertion: all stages remain the same when the new one is added

• problem: adding decision stage may influence another stage (like detection)

1. assumption of additivity: duration of all stages add together to yield the reaction time

• problem: stages might operate in parallel

1. assumes you already know what the stages are

• you probably don’t

why is donders 1868 work important today?

similar assumptions in modern research

similar criticisms can apply

donders’ contributions

1. the idea that you can measure mental processes

2. the choice reaction time procedurem

modern cognitive psychology

confirming evidence is weak

key methodological technique: eliminating alternative explanations

Hubbert and piercy experiments

Perception

means by which info acquired from environment via sense organs is transformed into experiences of objects, events, sounds, tastes

stages in perception

distal stimulus → proximal stimulus → perception

lack of correspondence

when perception does not correspond to distal stimulus

ex: perceptual (optical) illusions

paradoxical correspondence

when proximal stimulus does not correspond to distal stimulus but perception does

ex: moving objects, moving eyes

perceptual constancy

our perception of an object’s features remains constant even when viewpoint (and proximal stimulus) changes

• perception of size doesn’t change with distance

• perception of color doesn’t change with light

• perception of shape doesn’t change with angle

theorretical approaches

direct perception (stimulus theory)

constructivist theory

direct perception

enviornment provides all necessary cues

our brains are pre-wired to pick up cues

stimulus information is almost always unambiguous

biological motion

there’s a lot of information in the stimulus itself

constructivism

perception uses data from world and our prior knowledge and expectations

sensory information is often ambiguous

• must rely on knowledge/expectations

bottom-up vs top-down

• bottom up processing: processing that’s driven by external stimulus, rather than internal knowledge

  • direct perception claims perception is purely bottom-up

• top-down processing: processing that is driven by knowledge and expectations

  • constructivism: bottom-up and top down processes

depth perception

distal stimulus (the world) is 3D

proximal stimulus (on retina) is 2D

perceptual experience is 3D

• example of paradoxical correspondence

• how? → exploit environmental cues to recover depth

depth cues

linear perspective

shape

relative size

interposition

shadows

retinal disparity

accomodation

convergence

distal stimulus

light emitted from light source

some frequencies of light are absorbed by a distal stimulus

other frequencies of light are reflected

some of thsi light reaches your eyes

the eye

pupil: black dot

iris: colored part

sclera: white of eye

rods and cones

photo receptors

photo-chemical reaction takes place inside these cells when exposed to light

rods detect brightness

conesa re concentrated in fovea

most people have 3 types of cones: blue, green, red

potential

difference in charge inside vs. outside axon

threshold

potential must get above a threshold level for neuron to fire

• firing = generating an action potential

all or none

action potential always has same strength; either you get all of it (if above threshold) or none of it

propagation

once past threshold, active process (ion pumping) propagates action potential down axonl

refractory period

short period after firing before neuron can fire again

neural transmission

Summation: if combined effects at all synapsesbtake potential across axon above threshold, then neuron will fire an action potential

when 1 neuron fires it can cause neighboring cells to fire (or it can prevent them from doing so)

• so signal can move from one cell to another to another

communicate by sending chemical (neurotransmitters) across very small gaps between calls (synapses)

• triggered by action potential when it reaches axon’s end

so neural transmission is electrochemical

• involves an electrical action potential within cells

• involves a chemical neurotransmitter between cells

when neurotransmitter is released into synapse, it binds to receptorson target neuron

causes chain of events that eventually change potential across axon of taregt cell

• some neurotransmitters are excitatory

• others are inhibitory

same thing is happening at thousands of other synapses on target cell

mapping receptive field

center-surround organization

on center/off surround

off center/on surround

Functions:

• point detection

• edge detection

• light on dark or dark on light

Magno

transient response

large receptive field

movement/location

Parvo

sustained response

small receptive field

patterns/color/form

cerebral cortex

visual cortex

simple cortical cells

complex cortical cells

hypercomplex cells

• very specific chapes

• corners

• gaps

simple cell

• bar of light

• specific orientation

• specific retinal portion

complex cell

• edges

• movement

edge detection

edges in images correspond to edges of real-life objects

offer depth cues

allow parts of 3D objects to be identified

two visual pathways

dorsal “where” pathway

ventral “what” pathway

Positron emission tomography

mental activity → neural activity → blood flow → more radioactive tracer → more positron emitted

PET Study: spatial vs. object processing

spatial (where) task should activate occipital and parietal regions

object (what) task should activate occipital and temporal regions

PET results: kohler et al. study

population coding

need pattern of activation across a population of cells to recognize objects

pattern recognition theories

template theories

feauture theories

structural description theories

template theory

cubes

problem: transformations, obstructed objects

visual system feature decomposition

Visual system decomposes scenes into primitive features

cells in temporal lobe aren’t “tuned” to specific stimuli (no grandmother cell)

feature theory

perceptual representation: 3 horizontal lines, 1 vertical line, 4 right angles

memory representation: 3 horizontal lines, 1 vertical line, 4 right angles OR 2 horizontal lines, 1 vertical line, 3 right angles

evidence for feautures

physiology (recordings from neurons)

stabilized retinal images

visual search

pandemonium model

feature theory: problems

• realtionship between features → 1 line 1 half cirlce = P d b

• different arrangemnts of same features produce different objects

recognition by components

36 geons (geometric ions)

non-accidental properties

RBC: matching process

1. detect elementary features, edges

2. find non-accidental properties

3. determine component geons

4. match to memory

RBC: evidence

partial or degraded objects

object complexity

unusual orientations

deleting accidental vs non accidental

RBC: problems

similar objects

brain evidence?

context effects

but RBC is good at:

transformations

relationships between features

explaining how we make sense of nonsense objects

Top Down vs Bottom Up Processing

top = refers to areas of brain responsible for higher-level cognition. ex: gaol setting; decision-making

bottom = refers to lower-level areas of brain that receive input from sensation. ex: vision, audition

• top-down processing: processing that originates in higher cognition and proceeds downwards towards sensation

• bottom-up processing: processing that originates in sensory areas and proceeds upwards towards areas responsible for higher cognition

top dwon processing: 3 types

1. expectation/bias

2. context

3. higher levels of analysis that affect lower ones

expectation/bias

your own expectation or biases can affect the way you perceive something

signal detection

• frequently encountered task

• in general:detecting some “signal” in prescene of noise/distractions

signal detection theory (SDT)

addreses how we make these detection decisions

demonstrates how expectations/biases (top-down influences) effect perception

signal

something in the environemnt you are trying to detect

noise

things in environemnt other than he signal

sensitivity

how easy/difficult it is to discriminate signal from noise

• depends on how separable are signal and noise

• depends on how good your detetor is (vision, hearing, sense of touch)

bias

bias/tendency to say yes vs no (no vs yes). detrmined by expectations or payoffs

• it moves your responses between the yes and no rows of matrix

accuracy

% hits + % Correct rejections

Depends on:

• proportion of trials with signal present/not present

• bias

• sensitivity

signal detection matrix

hit: there’s a signal and you correctly detect it (yes and present)

miss: there’s a signal but you fail to detect it (no and present)

correct rejection: there’s no signal and you correctly say there was no signal (no and not present)

false alarm: there’s no signal but you say that there was a signal (yes and not present)

signal detection

example of how biases/expectations affect perception

context effects

when perception of an object is affected by its context/environment

examples

1. subjective contours

2. letter recognition

Subjective contours

we perceive triangles even though they’re nopt there

ambigupous letters

what you percieve depnds on context (B vs 13)