Unit #1

Cognitive psychology

study of human cognition (memory, perception, laguage)

Understand thought processes through

• introspect

• scientific experiments

RSVP sequence

rapid sequence of visual complex images (measures speed of vision)

Argument that vision is efficient

Potter: due to rsvp results and comprehension being fast

Counter argument that vision is efficient

Simons: Vision is course

due to change blindness and visual details being hard to retain

Gist vs details in regards to humans and devices

Humans: comprehending gist is easier than recalling visual details

For computers the opposite is true

Introspection about what is efficient or not

DOES NOT apply to all intelligent systems eg. computers

Why introspection is NOT sufficient

#1 disagreements: between individuals regarding dif aspects of mental capacity (visual vs gist)

#2 introspection accesses conscious thought: this is incomplete and misleading

freuds take on introspection

Consciousness is the tip of the iceberg— most thought are not accessable by conscious introspection

visual neglect

neglects side of space (right/left)

split brain patients

the two hemispheres of the brain are disconnected

neisser

looked deeper into how well we can attend to overlapping objects

how does attention change

attention can change psychological experience even tho stimuli remain the same

Dichotic listening

• two messages different ears

• attend to (repeat back what it says) ignore the other

Dichotic study explained and results

wanted to stimulate the experience of being at a busy event like a party

Noticed: sound presented, tone change and gender of who is speaking

ignored: language changing from english to german; speech from forward to backward; same words being repeated 35 times

(this same results are also seen with melodies

Selective seeing

task is to attend the cross, judge if the horizontal line is longer or the vertical line

• there are 3 trials , at the fourth they add a square by the line of judgement

what impact does attention modulating brain activity have

decides…

• what enters perceptional awareness

• whats later recognized

• level of brain activity

are we actually blind/deaf to unattended info?

• sometimes ignored info is noticed

• unnoticed info may affect behavior/ brain activity

Posner cueing paradigm

Attention can be allocated to spatial independent of eye movemnets

Orienting mechanisms

• exogenous (reflective)

• endogenous (voluntary)

exogenous

• engaged by peripheral cues

• fast

• occurs even with uninformative cues

endogenous

• engaged by central cues (words)

• slower

• occurs only with informative cues

Contrast between orienting mechanisms

• different location of cue

• speed

• control (reflex vs voluntary)

object based attention

sometimes attention appears to select an entire object compared to specific region of space

attentional shifting

affected by object structure (spreading attention along an object)

What happens when you divide attention between objects?

Much easier when they belong to the same object (same for comparing objects)

Mild form of neglect

extinction

What is extinction?

This is the mild form of neglect when you can see stimulus on both left and right but when presented with two stimuli they fail to notice the one further to the left

what is extinction modulated by

structure of objects occupying space

principle of cohesion

things that move together are parts of the same object (young infants know this through habituation)

Young infants know…

• Solidity: solid objects cannot pass through each other

• permanence: hidden objects continue to exist

• continuity: object cannot move from one point to another without passing through the points between

what part of the brain is needed for spatial attention?

parietal cortex

what results from unilateral parietal damage?

neglect

Visual search

finding target in space

types of visual search

• feature search (looking for an odd man out (easy)

• conjunction search (looking for a combination of features (hard)

Feature integration theory (Anna Treisman) evidence

1. feature vs conjunction

2. search asymmetry

3. illusory conjunction

types of maps visual display is coded by

• feature maps

• master locations

(locates features and binds features together)

feature vs conjunction

does not require attention →efficent conjun. requires attention → inefficient

search asymmetry

hypothesis: simple features are detected by produced unique activation on map

prediction: absence of feature should be harder to detect

illusory conjunction

hypo: simple features are bound freely moving around to location by the operation of focused attention

prediction: without attention features may be incorrectly bound to locations

balint syndrom

• patients have brain damage to both sides of parietal lobe

• see only one object at a time

• also known as “simultognosia”

neurophysiological evidence

• different brain regions code different features separately

• attention binds features together

repetition blindness

• failure to detect repetitions of visual stimuli in lists presented in a rapidly presented visual sequence

attentional blink

one target is detected people often fail to detect a second (different target)

Multitasking definition

conducting multiple tasks at the same time

attentional limits in multitasking

• tasks share general resources (the more resources a task draws the more inference it causes on other tasks) -inference is observed

• similar tasks share task specific limitation-inference is reduced when the two tasks become more different

cell phones + driving

you are twice as likly to miss a red light and reaction time is slowed

true or false, hands free inferences with driving just as much as hands on

TRUE

task switching frontal lobe

patients with frontal lobe damage have a difficult time switching tasks

multiple demand system

a set of fronto parietal regions involved in attention task control fluid intelligence

H.M case

underwent removal of bilateral medial temporal lobe for relief of severe epilepsy

• post surgery he became severely amnesic (lost all old memories and was unable to make new ones but retained older ones

Anterograde amnesia

difficulty learning new info

retrograde amnesia

inability to remember events that happen before brain damage occurred

some other ways people become amnesic

1. electroconvulsive treatment (for depression)

2. chronic alcoholism

What is the medial temporal lobe NOT?

• location of long term memories

• needed for the retrieval of long term memories

• location of short term memories

what IS the medial temporal lobe involved in

converting immediate short term mems into long term

stages of learning

• short term memory

• long term memory

process of learning

sensory info → short term memory → long term memory

what does verbal short term memory have in terms of capacity?

limited storage

manipulating short term memory

• occupy short term memory store

• should affect recency not primacy

manipulating long term memory

• change rate of presentation

• longer time to rehearse

• slower presentation → better recall

What happens on the way to long term memory?

consolidation

what happens when you have to go back to short term memory in order to move to long term?

rehersal

recency effect is seen in…

both short term and long term memory

duration is due to what?

lack of complete association

what type of learning is HM able to use

perceptual learning

declarative memory

explicitly available to concious recollection as facts, events and stimuli

nondeclarative memory

instances of perceptual stimulus— response, motor learning that we are no conscious of

patient A.M

• does not understand functions of common place objects

• semantic memory is severely damaged

• episodic memory is ok

encoding/memory

• we remember only what we have encoded

• what we encode depends on who where are, how we think and what we know

encoding

procedure that transforms something a person sees, hears, thinks or feels into memory

rehearsal types

-maintenance (little effort and ineffective)

-elaborative (effort and effective)

deep processing

meaning

shallow processing

surface characteristics

imagery technique

method of loci

• firm deep elaborative encoding

retrieval of an item from memory is linked to..

the context at encoding

RETRIEVAL IS BETTER WHEN THE CONTEXT IS IDENTICAL AT STUDY OR TEST

effects of memory delay

interference: retroactive interference: new experience interfers with recall of old memories

decay: diminution in the strength of connections among neurons that represent particular experiences

ST consolidation

seconds to mins

LT consolidation

over periods of moths,years and decades

lobe important for consolidation

medial temporal lobe

what helps with consolidation

sleep