Lecture 5 Flashcards
Information Processing Approach
- Ability to systematically convert input to output
- emphasises basic mental processes: attention, sensation, perception, memory
Methods of Studying Infant Sensory-Perceptual Abilities
• Habituation
– discrimination learning
– ‘learning to be bored’
• Preferential looking
– duration of looking at one of a pair
• Physiological responses
– heart rate
– observation of eye movements
• Evoked Potentials
– electrical conductivity of the brain
• Operant Conditioning
– response to one stimulus in a pair following reinforcement
Infant Vision
• basic capacities are present at birth
– can detect changes in brightness
– track a slow-moving object
• lack visual acuity
– ability to perceive detail
• visual accommodation
– ability to focus on objects at different distances
• optimal distance: about 20-25 cms
• takes 6 months to 1 year before can see as well as an
adult
• colour vision present at birth
– mature at 2 to 3 months
Pattern Perception
•Visual preferences --> •patterns that have light-dark transitions; contour --> •displays that contain movement --> •moderately complex patterns
•the human face
Depth perception
– newborns appear to have object constancy (i.e.,
perception of the object stays the same despite changes in
sensations)
• shape constancy
• size constancy
The visual cliff
– the visual cliff: Gibson & Walk (1960)
• a crawler (7 mo) will not cross the cliff
• can perceive the cliff by 2 months
• fear of drop-off requires crawling
• infants have intuitive theories – organised systems of
knowledge – that allow them to make sense of the
world
Infant Hearing
• can hear well before birth
• can recognise their mother’s voice, even in utero
• newborns discriminate sounds that differ in loudness, duration, direction & pitch
• a little less sensitive to soft sounds than adults
• infants respond to human speech & prefer speech
over non-speech sounds
• early differentiation between tones (e.g., happy &
sad)
Infant Taste
newborns can distinguish between sweet,
bitter & sour tastes
– show a clear preference for sweet
Infant Smell (olfaction)
– works well at birth
– will turn head away from unpleasant smells
– all babies prefer the smell of human milk over formula, even if
previously consumed formula
– at 1 to 2 weeks, breast-fed babies can recognise the smell of
their mother
– mothers can identify their newborns by smell
Infant Touch
• senses of touch & motion develop before birth
– sensitivity to tactile stimulation develops in a
cephalocaudal direction
– touch soothes a fussy baby
– massage helps premature infants to gain weight, be more
relaxed, & develop more regular sleep patterns
• at birth sensitivity to warm & cold
Infant- integrating sensory information
• 2 important accomplishments from infancy to childhood
– cross-modal perception: recognising through one sense an object
familiar through another
– a coupling of perception with action, leading to purposeful movement
Infant- Importance of early experience
sensitive periods
– a period during which an individual is more affected by
experience & has has a higher level of plasticity than at
other times of life
– certain sensory experiences are vital in determining the
organisation of the brain
Infants- Development of attention
• infants are “captured by” something
– they have an orienting system
• children are “directed toward” something
– they also have a focusing system that seeks out &
maintains attention to events
• from infancy: – increases in attention span – better able to concentrate on a task – attention becomes more selective – better able to ignore distractions – more systematic perceptual searches in order to achieve goals & solve problems
Problems with sensation and attention
Autistic Spectrum Disorder
• sensory sensitivity & integration difficulties
• attention problems
Adolescent- attention
– ability to sustain attention improves considerably
(myelination)
– more efficient at ignoring distractions
– can divide their attention systematically between two tasks
Adolescent- Hearing
– optimal acuity
– potential for damage
Adolescent- Taste
– slight decline in preference for sweets & an increased
sensitivity to sour tastes
– more likely to develop an acquired taste for previously
disliked or avoided foods
Adolescent- smell
- women generally demonstrate greater sensitivity than
men
The Adult
• Sensory and perceptual capacities decline gradually
– begins in early adulthood, becomes noticeable in 40s, &
typical by age 65 +
– can compensate for the deficits
• Losses take 2 forms
i) sensory thresholds are higher
• sensitivity to very low levels of stimulation is lost
ii) perceptual abilities decline
• difficulty in processing or interpreting sensory
information
The adult- sensory perceptual problems - Vision
Vision
– pupils become smaller & do not respond as much
when lighting conditions change
– lens becomes denser & less flexible
• can’t accommodate to bring objects at different
distances into focus
• presbyopia: decreased ability to accommodate
objects close to the eye
The adult- sensory perceptual problems - Hearing
– most have at least mild hearing loss
– presbycusis: loss of high-pitched sounds
• more common & earlier in men
– some difficulty with speech perception
• may be cognitive or sensory
• background noise a problem
– novel & complex tasks problematic
The adult- sensory perceptual problems - Smell and Taste
– general decline in sensitivity to taste
• more so older men
– ability to perceive odors typically declines with age
The adult- sensory perceptual problems - Touch
– sensitivity for touch is gradually lost from middle
childhood, few implications
– less sensitive to changes in temperature
Memory Systems *******
Memory processes
– encoding: getting information into the system
– consolidation: processing & organising information
– storage: holding information in long-term memory
– retrieval: information is obtained from long-term
memory
–> constructive, not static process
–> Long Term: explicit or implicit
The Infant- memory
• can habituate at birth
• can imitate actions
• by 6 mths can imitate a novel action after a delay
• operant conditioning - make a mobile move with
their leg 2 to 4 weeks later
•cue dependant & context specific
The Child- memory
Improvements in Basic Capacities
• maturation of the hippocampus & other parts of
the brain involved in consolidation of memory
• short-term memory capacity improves,
particularly between ages 6 to 13 years
Developmental changes in short term memory
• speed & efficiency of mental processing improves
– allows simultaneous mental operations
– basic mental processes become automatic;
frees working memory
– greater knowledge of a domain increases the
speed with which new, related information can
be processed
Improvements in memory strategies (mnemonics)
- increased use of rehearsal at about 7 years
- master organisation (i.e., classifying items into
meaningful groups) by 9 or 10 years - elaboration (i.e., actively creating meaningful links
between items) is the last strategy to develop
Improvements in knowledge about memory
• metamemory: knowledge of memory & understanding how to monitor and regulate memory processes
– present in young children
– gets better with age
Improvements in world knowledge
• children’s knowledge of a content area (i.e.,
knowledge base) affects learning & memory
performance
– expertise allows children to form more & larger
mental chunks, which allows them to remember
more
Autobiographical Memories
childhood amnesia: few autobiographical memories from
1st years of life
• limited working memory capacity
• lack sufficient language skills
• lack a sense of self
• early verbatim memories are unstable & likely to be lost
The adolescent - memory
• new strategies emerge (e.g., elaboration;
approach to study)
• strategies are used deliberately & selectively
• basic capacities increase (e.g., processing speed)
• knowledge base increases
• metacognition improves
The adult- memory
• Domain specific knowledge base increases
(expertise)
– think more effectively
• remember more new information
• solve problems effectively & efficiently
• automaticity
The older adult- memory
some change is inevitable
• cross-sectional research
• declines typically not noticeable until 70’s
• individual & task variability
Explaining memory decline
• changes in basic capacities
– decline in capacity to use working memory to operate actively &
simultaneously on multiple pieces of information
– more difficulty ignoring irrelevant information
– attention becomes more effortful (motivation)
• older adults learn new material more slowly, learn it less
well, remember less
– timed, unfamiliar tasks
– more so recall than recognition
• sensory abilities
• education, health & lifestyle
• negative beliefs affect memory skills
Autobiographical memories #2
personal significance • distinctness • emotional intensity • life phase – ‘memory bump’; ages 15 – 25 years
