ch 05 infancy note by na9tkUr5


									                                      Chapter 5 INFANCY

Sensation: the detection of sensory stimulation
Perception: the interpretation of sensory input
                           THE NEWBORN’S READINESS FOR LIFE
Newborn Reflexes – involuntary, automatic response to a stimuli
       Survival – adaptive value, satisfy needs;
               breathing, sucking, swallowing
       Primitive – not as useful, disappear first year
               Babinski, swimming, grasping

Infant States: six levels of arousal
        Pass through predictable pattern of states
        70% of time asleep
 Developmental Change in Infant States
        Overall sleep decreases, duration of episodes increases
        REM – declines; less need for stimulation while asleep (Autostimulation theory)
        SIDS – leading cause of infant mortality

       Functions and Course of Crying
              State communicating distress
                      Developmental changes in crying
                            Tends to diminish after first three months – maturation of brain,
                            increased responsiveness from parents
                            Shrill and nonrhythmic may indicate brain damage

The Preference Method
       Discriminate between stimuli (looking chamber)
The Habituation Method
       Familiarity leads to a lack of response
       Dishabituation – response to new stimuli
The Method of Evoked Potentials
       Present a stimulus and record brain waves
              Discrimination of stimuli produces different brain wave patterns.
The High-Amplitude Sucking Method
       Rate of sucking on a pacifier controls the presentation of a stimuli, shows preference and

                             INFANT SENSORY CAPABILITIES
       Discriminate sounds based on loudness, duration, direction, and frequency
       Prefer mother’s voice to other women
       At 3-6 months, sensitive to phonemes, even better than adults (if sounds are not part of
       the adult’s spoken language)
       Hearing loss can adversely affect development (often due to ear infections)
Taste and Smell
       Prefer sweet over sour, bitter, or salty
       Avoid unpleasant odors
       Recognize mother by smell (if breast-fed)

Touch, Temperature, and Pain
       Touch enhances development, allows exploration of environment
       Sensitive to temperature
       Sensitive to pain – even at 1 day

         Least mature sense
         Detect changes in brightness
         Can see patterns
         See colors, although discrimination is good by 2-3 months
         Poor acuity, see as well as adults by 12 months

                             VISUAL PERCEPTION IN INFANCY
Perception of Patterns and Forms
       Early Pattern Perception (0 to 2 Months)
               Prefer high contrast patterns
               Prefer moderately complex patterns
               Prefer patterns that move

         Later Form Perception (2 months – 1 year)
                More sensitive to movement
                Begin to perceive objects as whole forms
                Use subjective contours
                Results from interaction between visual sense, biological maturation, and learning

Perception of Three-Dimensional Space
       Size Constancy
               Present at birth, not fully developed until 10 – 11 YEARS old
               Movement cues important (1-3 months)
               Binocular cues important (3-5 months)

         Pictorial Cues (monocular)
                 develop by age 6-7 months

         Development of Depth Perception
               Use of visual cliff
                      Most infants (90%) at 6½ months (crawling) perceived depth
                      2 month-olds showed decrease in heart rate – a sign of interest, but not
                      Experience through motor development is important
                                 INTERMODAL PERCEPTION
Are the Senses Integrated at Birth?
       Yes: reaching for objects that are seen
       Yes: looking in the direction of sounds
       Yes: expecting to see source of sound, or to feel objects that were reached for

Development of Intermodal perception
      1-month-olds -- weak oral-to-visual perception
      4 months – intermodal matching between vision and hearing
      4-6 months – match tactile and visual sensations

Explaining Intermodal Perception
       Intersensory redundancy hypothesis
               Amodal detection of a stimulus aids in development and differentiation of
               individual senses.
               At birth – perception is amodal
               Experiencing multimodal stimuli leads to intermodal perception.

Language – become sensitive to sounds important to specific language
       English versus Chinese and “r” and “l”
Music – familiar with own culture’s music
       Western major/minor versus Javanese scale
Growth of perceptual skills includes adding new skills and losing unnecessary ones
Culture determines which sensory inputs are distinctive and how to interpret those inputs

       Change in behavior that
             Produces a new way to think about, perceive, or react to the environment
             Is the result of experience
             Is relatively permanent

Habituation – process by which we stop responding to a repeated stimulus

Dishabituation – attending to a new stimulus
       Developmental Trends
              Possible before birth
              4 months – may take long exposure
              5-12 months – need a few seconds
              10-14 months – habituate to objects and relationships between objects

       Individual Differences in Habituation
              Some habituate slowly and forget rapidly
              Others habituate rapidly and forget slowly
                      Rapid habituation between 6-8 months
                             Better language skills in second year
                             Higher IQ later in childhood
Classical Conditioning
       Unconditioned stimulus (UCS) elicits an unconditioned response (UCR)
       Neutral conditioned stimulus (CS) paired with (UCS)
       Eventually CS elicits a conditioned response (CR)
       Possible for newborns, but must have survival value

Operant Conditioning
      Learner emits a response (operates on environment)
      Associates this action with the consequences it produces
             Repeat favorable, limit unfavorable
      Newborns learn very slowly, rate increases with age
      At 2 months, memory is context-dependent

Observational Learning –
      Attend to a model and form a symbolic representation of model’s behavior
              Newborn imitation – possible at 7 days old, if part of behavioral repertoire
              Imitation of novel responses – reliable between 8-12 months old
              Immediate imitation at first, deferred imitation later

Observational Learning –
              14-26 months old
                     Emulation is possible – observational learning without a model

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