4difference between species EQHuman7.4Cat1.0Dolphin5.3Horse0.9Chimpanzee2.5Sheep0.8Rhesus Monkey2.1Mouse0.5Elephant1.9Rat0.4Whale1.8RabbitDog1.2 ParrotHumans do not have the largest brain – but they have the largest EQ.Encephalization Quotient (EQ)Average brain mass/body weights for a species.Average for species/average mammalian value.EQ+IQ
5brain developmentMost brain development happens outside (instead of inside) the wombMonkey newborn 70% adult sizeHuman newborn 25% adult sizeMost growth occurs in first 3 yrs3 yrs old 80% adult size5 yrs old 90% adult size
6developmental processes Neurogenesis – proliferation of neurons through cell division250,000 cells “born” every minuteSynaptognesis – formation of connectionsEach neuron forms 1000’s of connectionsAxons elongate towards specific targetsDendritic “trees” increases in size and complexityBy 6 months 2 x more synaptic connections
8developmental processes Synaptic pruning – elimination of excess synapsesStreamlines neural processingWithout synaptic pruning, children wouldn't be able to walk, talk, or even see properly.Myelination – insulating sheathHappens at different rates into adolescenceCertain areas are myelinated first
10importance of experience Plasticity – brain’s ability to change w/ experienceExperience-expectant plasticity (experiences present throughout evolution)Economizes on material encoded in genesDevelopment will occur within a normal range of environmentsLevel of vulnerability in timingSensitive periodsExamples?visionlanguage
11announcements Psychology Club Event Feedback for in-class debate Volunteering in the Community9/29 (next Weds) 5:15pm, ECTR 116Feedback for in-class debateGroup write-ups – pick up after class.Study session for Exam 019/29 (next Weds) 7:00pm, ECTR 11335 MC/TF questions (2pts each)2 essay q’s (20 pts + 10 pts) – I will give you potential q’s in advance
14importance of experience Experience-dependent plasticity (experiences of individual)Brain sculpted by idiosyncratic experiencesResponsive to richness of environmental stimuliImportant in development of expertiseMore brain resources dedicated to processingE.g. musicians’ cortical representation of hands
20importance of sleepREM sleep – critical for neural development in brain, esp. for activity-dependent developmentE.g. visual systemFacilitates learning/memorySleep deprivation linked with later problemsE.g. ADHD, learning disabilitiesBabies most at risk of disruptionPremature infants in IC units
21stress and brain development Exposure to excessive stress hormones is bad for brain development.Early symptoms of PTSDThe brain can become incapable of producing normal stress responses.Hyper-vigilance (Ghosts in the Nursery)Emotional flatnessPhysical/emotional abuse and neglect can be equally damaging.
23attachment theoryAttachment refers to the close, emotional bond between an infant and his/her primary caregiver.Psychoanalytic Theory (Freud)Driven by oral needs during the first yearEmphasized early experiences on later outcomesBehaviorist Perspective (Skinner)Driven by the need for foodLearns to associate contact with mother with foodMother’s closeness continually reinforced
24attachment theory Ethology (Lorenz) Rooted in Darwin’s Evolutionary TheoryFocused on the adaptive value of behaviorBond necessary for survivalImprinting
25primary criticismsLove (i.e., attachment) seen as secondary to instinctive or survival needsHarlow believed that the need for love and affection was necessary for survival
26announcments Psyc Club – Volunteering in the Community Exam study sessionWeds, 7-9pm, ECTR113Friday – Ch 4-6 Ask yourself Q’s dueHow do you want to spend Friday?A) lectureB) ask yourself q’s and study guide!Exam 01- Monday!
27Harlow’s monkeys (1958) Early work with monkeys Cloth & wire mother Only one equipped with feeding apparatusMonkeys randomly assignedObserved for 5 monthsBoth groups preferred cloth mother
28Contact Time with Wire and Cloth Surrogate Mothers Infant monkey fed on cloth mother24.Infant monkey fed on wire mother....18..Hours per day spent with cloth mother.12Contact Time with Wire and Cloth Surrogate Mothers.Mean hours per day.6..........Hours per day spent with wire mother1-511-1521-256-1016-20Age (in days)
30attachment theory John Bowlby Observations of children in institutionalized careInfant has built-in behaviors to keep parent closeGives way to true affectionate bondServes 2 purposesSecure baseInternal working model
31attachment theory Mary Ainsworth (1979) Developed Strange SituationWork revealed 4 types of attachment behaviorSecurely AttachedInsecure AvoidantInsecure ResistantInsecure Disorganized
37mirror neurons Found in the frontal and parietal lobes Fire when you You engage in an activity (reaching out one’s hand)You observe someone else engaging in the same activity.Fire more strongly when action has some purpose or contentreaching out one’s hand for a cup.MN’s play a clear role in learning/imitation.May also play a role in “mind-reading”grasping intentions, goals, desires.
40crying Crying –communication of emotion Response to distress Soothing Development of emotional self-regulationMastery of environment – agencyBiofeedback loopSoothingSwaddling – tight wrapping of baby in clothTouchSweet tasteSoft, rhythmic soundsVibration
41crying disorders Colic (1 in 10 infants; birth – 12 weeks) Extended periods of intense cryingCause unknownImmature nervous systemHyper-sensitivityDigestive problemsProlonged crying (beyond 12 weeks)Exhibit developmental and behavioral disorders
42crying disordersProlonged crying expose the brain to high levels of cortisol, adrenaline, and other damaging chemicals.Damage to hippocampusReduced levels of vasopressin and serotoninReduced levels of emotional regulationImpaired memoryIncreased levels of aggression/violence/bullyingIncreased levels of anxiety disorders
43early emotional expression Earliest emotionglobal arousal states of attraction and withdrawalset the stage for further developmentdevelop into well-organized, sustained signalsBasic emotionsemotions that can be directly inferred from facial expressions.happiness, interestsurprise, fear, angersadness, disgust43
44Basic emotions:Universal across all human culturesPresent in other advanced speciesInclude guilt, shame, embarrassmentA&BAll of the above
45emotional self-regulation Strategies for adjusting emotional state to a comfortable (adaptive) level of intensity in order to accomplish goalsInfants: withdrawal, distress, crying -- need soothing4 mos: shift focus of attention1 year: approach/retreat from stimulusParent response to distress is importantSympatheticchild more easily soothed, more self-regulatedNon-responsive (wait to intervene)child enters into rapid, intense distressharder to soothedoesn’t develop self-regulation45
46emotional self-regulation When an infant’s needs are met, they can focus on the world around them and explore.Their brains take in and adapt to stimulation from the external world.When they aren’t met, they become fixated on trying to get their needs met.They stop exploring and shut out other stimulation from the external world.
47emotions of othersEmotional contagion: babies match the emotional expressions of caregiver7-10 mos: infants perceive facial expressions as organized patterns, can match facial expression to emotion8-10 mos: social referencing- relying on another person’s emotional reaction to appraise situation (e.g.- visual cliff)Still face experiment47
48Mirror neurons help infants experience others’ emotions: Yes, because they help them match emotional facial expressionsYes, because they stimulate a matching internal experienceYes, because they allow infants to empathize with others.A&BNo, because mn’s are only involved in imitation of physical behavior
49social referencing Example of how adults help child regulate emotion Permits toddlers to compare their assessments of situations with othersHelps young children move beyond simply reacting to emotional messagesVisual cliff experiment49
50temperament Constitutionally based individual differences in EmotionMotor functionAttentional reactivitySelf-regulationInfluences the way that children develop, display, and control emotionsFoundation for later personality50
51temperament styles Types Differences in sociability EasyDifficult“Slow to warm up”Differences in sociabilityDifferences in punishment/rewardWhich child will be harder to reward/punish?Easy childDifficult child51
52temperament styles What else affects the development of temperament? GenderCultural differencesGoodness of fit (with parents/environment)52
56theory differences Piaget stage theory Core-knowledge theory Child as “blank slate” (everything learned)Focus on learning as a process within individualsCore-knowledge theoryChild possesses innate knowledge (domains of thought)Socio-cultural theoryFocus on learning as a social process between individuals
57Piaget’s theoryConstructivist approach – children actively construct knowledge for themselves in response to their experiences.Child as scientist:Generate hypothesesPerform experimentsDraw conclusionsChildren learn many things on their ownwithout the help of instruction from adults.Children are intrinsically motivated to learn.Discontinuous (qualitative) changedifferent ages think differently.
60Information processing Computational approach – cognitive development as a passive maturation process that occurs over time.Child as a computational systemChildren undergo continuous (quantitative) cognitive changeDevelopment through increasingly sophisticated hardware and softwareFaster and more efficient processing, larger memory bank, better learning “algorithms”More content knowledge (learned facts) to draw upon
61Core-knowledge theories Child as well-adapted product of evolutionEmphasis on sophistication of children’s thinking in areas that have had evolutionary importance.Eg. environment navigation, face recognition, languageNaïve physics, psychology, biologySome advanced capacities already present (innate)Move from “general” to “domain specific” specialized learning mechanisms
62Naïve physicsInfants have a surprisingly sophisticated understanding of how the physical world works.
64understanding intentions They also have a pretty sophisticated understanding of how the psychological world workse.g., they understand that there are goals and intentions and that only certain creatures can have them.