PSYC 206 Lifespan Development Bilge Yagmurlu

Chapter Overview Physical Growth Sensing the Environment The Organization of Behavior Becoming Coordinated with the Social World Temperament

Physical Growth In 12 weeks, infants Gain weight Grow Expanding head circumference Growth charts

Brain Development The brain at birth Contains most of the neurons it will ever have.

Brain Development Growth in brain size as a result of: Neuronal connections Synaptogenesis Synapse: Site where a nerve impulse is transmitted from one neuron to another.

A nerve cell, or a neuron, consists of many different parts. Brain Development A nerve cell, or a neuron, consists of many different parts. 6

Brain Development Myelination Insulates axons and speeds transmission of impulses 7

Central Nervous System Brain, brain stem and spinal cord

Central Nervous System Spinal cord: extends from below the waist to the base of the brain. Brain stem: controls reflexes as blinking and sucking and vital functions such as breathing.

Central Nervous System Cerebral cortex: outermost layer and center for perception of patterns, decision making, speech, planning and execution of complex motor sequences 10

Development of the Brain Two major classes of development: Experience-expectant process Experience-dependent process 11 11

Development of the Brain Experience-expectant process Under genetic controls, occur in any environment Exuberant synoptogenesis Species-universal experiences are required for fine-tuning neural connections. Synaptic pruning

Development of the Brain Experience-expectant process Species-universal experiences are required for fine-tuning neural connections.

Development of the Brain Experience-dependent process Initiated in response to experience These processes have evolved to allow the organism to take advantage of new and changing information in the environment. 14

Development of the Brain Experience-dependent process Example: work on enriched environments by Rosenzweig and colleagues. Impoverished environment Rat brain cell Enriched 15

Development of the Brain

Sensing the Environment Newborns’ sensory systems Variations in functioning show importance of systems for survival Indications of sensation Habituation Dishabituation

How to measure sensory reactions? Measure reaction to stimuli Does a baby turn her head in the direction of a sound? Habituation paradigm: relies on infants’ tendency to pay less and less attention to a repeatedly presented stimulus dishabituation

Sensing the Environment Newborns’ sensory systems Variations in functioning show importance of systems for survival Indications of sensation: perceiving an object or event

Early Sensory Capacities as opposed to the views of earlier century thinkers (e.g., John Locke’s tabula rasa), babies enter the world with some well-organized behaviors sensory capacities: visual, auditory, taste-related, and tactile capacities are all functioning but, some capacities are more mature than others looking, sucking, and crying are 3 behaviors that, unlike reflexes, are often not elicited by a discrete, identifiable stimulus

Early Sensory Capacities

Hearing Sensitivity to phonemes 2-month-olds can perceive distinctions used in all the world’s languages By about 6 to 8 months of age, only the sounds made in the language(s) they hear

Hearing Infants can distinguish the sound of the human voice from other kinds of sounds, and seem to prefer it. Are particularly interested in speech with the high pitch and slow, exaggerated pronun- ciation

Vision Newborns are very nearsighted Visual acuity for one foot away Newborns are able to: scan their surroundings perceive patterns and distinguish among forms. show a preference for faces distinguish their mother’s face

Vision: an artist’s conception

Perception of Faces

Taste and Smell Responses to Sweet tastes and smells Example: breast milk Sour, bitter, and salty tastes

Taste sensitivity to taste may be present before birth newborns prefer sweet substances than plain water-- suck longer with fewer pauses

Intermodal Perception The simultaneous perceiving of an object or event by more than one sensory system

The Organization of Behavior Behavioral organization is important for Interacting more effectively and adaptively with their surroundings Increasing physical control and coordination Smiling in response to the smiles of others Performing deliberate actions

The Organization of Behavior Reflexes Highly organized specific involuntary responses to specific types of stimulation Building blocks for action Some are adaptive, temporarily or permanently Unusual patterns may be informative about development

Grasping Reflex When a finger or some other object is pressed against the baby’s palm, the baby’s fingers close around it

Piaget’s Theory of Developing Action Sensorimotor Stage Perspective Infants gain knowledge largely by coordinating sensory perceptions and simple motor responses

Becoming Coordinated with the Social World Infants’ survival depends on: Responsive caregivers Coordinate their own actions with those of caregivers

Crying Primitive means of communication The effects of infant crying: Evokes a strong emotional response in adults Warning that something may be wrong Certain distinctive patterns may indicate difficulties

Temperament Individual differences in infants Traits both genetic and environmental bases Traits Consistent across situations Some stability over time 37 37

Temperament constitutionally based individual differences in emotional, motor, and attentional reactivity and self-regulation” constitution: biological make-up. interaction of heredity, maturation and experience It refers to general disposition and overall behavioral style 38 38

Classifying Temperament Chess and Thomas classified babies as one of following: Easy babies Difficult babies Slow-to-warm-up babies 39 39

Temperament Problems with general profiles: Example: Difficult temperament 40 40

Classifying Temperament Rothbart and colleagues’ 3 dimensions: Reactivity Affect Self-regulation 41 41

Measurement of Temperament Lab Observation expose children to strangers or toys and note child’s responses. Widely used and reliable measure Some problems/limitations: researcher can examine limited range of behaviors lab setting may elicit atypical expressions of temperament child’s behaviors can be influenced by transient factors such as mood 42 42

Measurement of Temperament Questionnaire Researcher asks adults who know the child well Provides rich source of data on child’s temperament 43 43

INFANT BEHAVIOR QUESTIONNAIRE M. K. Rothbart Temperament dimensions: Activity Level Smiling and Laughter Distress and Latency to Approach Sudden or Novel Stimuli Distress to Limitations Soothability Duration of Orienting 44

INFANT BEHAVIOR QUESTIONNAIRE M. K. Rothbart Activity Level Child’s gross motor activity, including movement of arms and legs, squirming and locomotor activity.   Smiling and Laughter Smiling or laughter from the child in any situation. Distress and Latency to Approach Sudden or Novel Stimuli The child’s distress to sudden changes in stimulation and the child’s distress and latency of movement toward a novel, social, or physical object. 45

INFANT BEHAVIOR QUESTIONNAIRE M. K. Rothbart Distress to Limitations Child’s fussing, crying, or showing distress while: a) waiting for food; b) refusing a food; c) being in a confining place or position; d) being dressed or undressed; or e) being prevented access to an object toward which the child is directing her/his attention.   Soothability Child’s reduction of fussing, crying, or distress when soothing techniques are used by the caretaker of child. Duration of Orienting The child’s vocalization, looking at, and/or interaction with a single object for extended periods of time when there has been no sudden change in stimulation. 46