PSY210 Lecture 5.docx

PSY210 Lecture 5 Growth -changes in height and weight rapid growth in first 2 years at 2, half of adult height and 4 X’s birth weight Physical Growth -2 month old fetus= half head -adulthood 10-12% of entire length is head, legs half of length What Determines the Timing of Puberty? -Factors contributing to the onset of puberty: Genetic influences Athletic training—competitive gymnasts enter puberty later in life because they don’t have body fat on them and because of rigorous activity Parent-child relationships -girls who don’t have a father around enter puberty earlier Stress People are Growing Taller -reasons for increasing height and weight: -health and nutrition have improved in many countries (especially for height) nutritional deficits in one generation and next noneso increased height in those children -socioeconomic conditions have improved good nutrition more available so more taller people Obesity Epidemic -Obesity: an individuals weight is at least 20% in excess of average weight for their height and frame -obesity has been on the rise in North America children for many years -most Canadian children are inactive and overweight linked to increasing caloric intake patterns -ethnic group membership -genetic factors play a crucial role -education and income levels -modeling by others (adults eating large portions of unhealthy food and children monitoring that behavior) -obesity linked to many health problems -to helpcut down children’s video game playing and tv watching (most effective) causing children to be more active Sensation versus Perception -objects with identical physical size look different -images with same retinal image size can look like they are different sized due to the way our brain interprets images adaptive, good because helps us make sense of the world -some species sensitive to perceptual info out of our range (dogs) -other species pick up types of info that humans simply don’t use (homing pigeons appear to use magnetic fields to navigate) -human perception also changes across lifespan -Sensation: detection of stimuli by the sensory receptors detection and discrimination -Perception: interpretation of sensations to make them meaningful -Preferential looking (Robert Fantz) -habituation -operant conditioning tells us how child is perceiving things in the world Habituation with Pacifier -child suck in accordance to what is presented Visual preference -children prefer to look at patterned stimuli Visual acuity: children favor stripes and when stripes disappear no longer can differentiate between solids and stripes work out what child is actually seeing 6-8 months good acuity Color Perception -have color vision but don’t see colors like us -by 4 months, can discriminate all basic colors Audition -auditory experience begins in 3 trimester of pregnancy -electrophysiological studies with preterm infantsif born early, can still survive to give idea of auditory system of child still in womb -change in heartbeat or movements in response to sound -postnatal memory for fetal auditory experiences studies with mother’s voice Perception of Frequency -different frequencies at different ages -parallel for different age groups (3 months, 6 months, 12 months, adults) -threshold dropping towards adulthood -infants sensitive to same range as adults -audibility curves for infants and adults parallel -sounds for thresholds for infants are higher than those for adults at all frequencies -thresholds continue to improve throughout first year of life Sound Localization -newborns hear loud rattle (80 dB) when rattled 20 cm from right or left ear as evidenced by their turning behavior slow response by infants in comparison to adults What if there is no auditory input? -People born deaf what happens? -visual areas increase in size and “jobs” -auditory areas may be taken over for visual function -improved attention to movement in the periphery -specific to deafness: not sign language (because of no auditory input) -language is visual-spatial, but still in the left hemisphere (for anyone who learns a visual/spatial language) Crossmodal Integration Intermodal Perception: more than one modality to identify a stimulus Locke predicted that if it were possible to tap into mind of neonate and study and understand initial perception and understanding of world, as well as the effect of total sensory deprivation on subsequent mental development WILLIAM JAMES on INFANCY ”one great blooming bussing confusion” Meltzooff -young infants presented with pacifier with different shapes, smooth and nubby -presented with pictures, if had smooth looked at smooth pacifier and vice versa children sensitive to tactile info and how tactile info will look -IMITATION STUDY: -go up to infants make 1/3 faces (stuck out tongue, opened mouth, pout) -much better at chance than presenting imitation -some sort of sensitivity between own articulators and what they see BOUNCING EXPERIMENT (duple meter) -can change how children hear music in response to how you bounce them to the music -bounce child to duple beat or triple -changes child perception of music, perceived in duple if bounce to duple and vice versa So what do we know? Newborn have a more orderly perceptual world than “blooming, buzzing confusion” but their world is NOT adult like -newborn infants are tuned in to socially significant stimuli (faces and voices) BUT EXPERIENCE SHAPES THE DEVELOPMENT OF THESE INTITIAL CAPACITIES Early Emotional Development -emotions: subjective reactions to the environment, usually accompanied by some form of physiological arousal expressed in some form of behavior Infants are emotional… Interest, fear, joy, disgust sadness, and anger -don’t hide emotions, express them -smiling and laughter are first expressions of pleasure newborn infants display reflex smiles infants show preferences for human faces special smiles for mothers—Duchenne smiles, display smiles: jaw drop + duchenne and for toys not all babies smile with equal frequency; individual, cultural, and sex differences exist a wide array of stimuli can make baby laugh Theoretical perspective on emotional development -genetic-maturational perspective: emotion have biological underpinnings identical and fraternal twin research -learning perspective: individual emotion expressions result from individual experiences experiences elicit and reinforce responses -functionalist perspective: help in achieving goals and adapting to the environment emotional signals (social cues) guide behaviors Emotional Expressions -primary/basic emotion: interest, distress, disgust, and contentment (at birth) anger, sadness, joy, surprise, fear (emerge 2-7 months) biologically programmed? Built in maturational responses -secondary/complex emotions in second year embarrassment, shame, guilt, envy, pride self-conscious or self-evaluative emotions initially, only expressed when adult is present -eventually expressed in absence of adults Interpreting others’ emotions -recognizing facial emotion 3 months-discrimination of emotional faces (preferences for happy over grump faces) 5-7 months- categorization, understanding (matching emotional voice with emotional face) social referencing (7-10 months): looking to others to see their reaction to a situation to help interpret a situation empathy (18-24 months, conversations) Recognizing Emotions in Others -another challenge that infants confront within first half year of life is that of learning to recognize emotional expressions in others -in general, children are more proficient at producing than at recognizing emotions -the two abilities are positively related: children who are skilled at one are typically skilled at the other Empathy requires awareness of self versus others -by age of 2, almost all children show self-recognition important in understanding that there are others out there and they feel differently than I d