Child Psych Quiz #1

Modules 1, 2 & 3 so far, being updated throughout the day by Cassatt based on the slideshows

Development

Refers to the process by which an organism (human or animal) grows and changes through its life-span

How do we understand ourselves and others?

Introspection & self-awareness

Descriptive/Observational Studies

Direct observation in naturalistic setting:

• Observing behavior as it unfolds in natural settings

• Monitor what we see: Descriptive data

• Does not involve any manipulation of variables

Ex: Observing children on a playground to study
their social interactions and play behaviors without
any interference

Limitations: can not be used to explain behavior, observer effect, observer bias

Correlational Studies

A study designed to measure the degree of relationship (if any) between two or more events, measures, or variables
• How one variable is related to another
✓ Direct/Positive correlation (high scores in one measure match high scores in the other)
✓ Inverse/Negative correlation (high scores in one measure match low scores in the other)

Experimental Studies

Three variables:

• Independent variable: manipulated variable, considered to cause variations on the dependent variable

• Dependent variable: outcome effect in an experiment → changes in the variable considered to be dependent of the indepent variable

• Extraneous variable: not controlled variable that causes an impact in the experiment

Types of Groups in Experimental Research:

1. Experimental group - a set of items or people under study to determine the effect of an event, a substance, or a technique

2. Control group - serves as a standard or reference for comparison with an experimental group

Experimental Research Design

Cross-sectional design

• Evaluation at one time point with different individuals/groups

• Fast and cost-effective → no attrition

• Allows large, diverse samples

• Good for analyzing group differences

The do not give insight into the causal processes involved in developmental change.

Different participants, different ages, same historical time

Longitudinal Design

The investigator follows certain individuals over a given time period, measuring change

Example:

• Assessed at 5, 10, and 16 years

• Intellectual performance, good conduct and emotional healht

• Family background factors (ex. family income/education)

• Outcome variables → income, educational achievement, social/personal adjustments, life satisfaction at age 26 & 34

Same participants, different ages, different historical time

Limitations of longitudinal studies

• Attrition (gradual reduction in numbers, size, strength, or structure)

• Time-consuming

• When the study was initially designed decades ago, it may not have asked the sort of question we now find most interesting

• Conclusions will refer to developmental outcomes for people born decades ago

Cohort design

Different participants, same ages, different historical time

How do we obtain information?

Quantitative and qualitative methods

Interviews, focus groups, experimental tasks, questionnaires/surveys

Quality of research

Determined by the RELIABILITY and VALIDITY

Reliability

A reliable method is one that would give the SAME answer if you, or another investigator, were to repeat the measurement in the same conditions

Validity

Refers to whether the data we obtain are meaningful

Ecological validity - valid in the sense of meaningful in the “real world” (ex. in a laboratory, would it work?)

Ethical Issues

Informed consent

Confidentiality

Lack of harm to participants themselves or to others

Ontogenesis

• Development of behavior within the individual across the lifespon

• Encompasses biological maturation, learning, and context-driven changes

Phylogenesis

• Evolution of behavior across species over deep time

• Addresses inherited behavioral patterns shaped by natural selection

• Comparative lens: birds, mammals, primates (monkeys and apes)

Zygote

All humans begin as a single zygote (fertilized egg) → zygote undergoes divisions and differentiation

Cells, nuclei, and chromosomes

• Each cell contains a nucleus with chromosomes

• Chromosomes are arranged in pairs (humans: 23 pairs)

• Chromosomes carry genes along their length

• Humans: 23 pairs of chromosomes (including s*x chromosomes X and Y)

Genes and DNA

Genes are DNA segments positioned along chromosomes

Genes provide instructions for producing materials needed for growth and development

Genome

the entire sequence of an organism (species-wide blueprint)

Genotype

An individuals’s genetic constitution (specific alleles)

Genotypes and possible phenotypes:

• BB → brown eyes

• Bb → brown eyes

• bb → blue eyes

Alleles

Alternative forms of the same gene with different effects

B = brown eyes (dominant)

b = blue eyes (recessive)

Genetics of behavior

• Behavioral traits can be influenced by genes

• Some genes have strong effects on specific characteristics → others have smaller, distributed effects

• Most psychological traits involve multiple genes with small effects → outcomes are probalistic

Twin studies

Twins occur in about 1/80 pregnancies

Monozygotic (MZ, identical): one zygote splits → genetically identical, same sex

Dizygotic (DZ, fraternal): two eggs, fertilized by two sperm → 50% shared genes, like siblings

Identical twins often show greater similarity to one another than fraternal twins

Confounding variables of twin studies

Identical twins are treated in more similar ways by parents
than are fraternal twins, so that their environment is more similar as well as their genetic inheritance

Solution:

• Studies on identical twins reared apart

• Comparing adopted and non-adopted siblings (Plomin et al., 2013).

Attachment

Influence of shared environment (e.g. general maternal sensitivity to infants) and non-shared environment (e.g. friends)

Small role of genetics

Jzendoorn et al. (2000)

Developmental neuroscience

• Study of how the nervous system develops and changes over time

• Examines growth, differentiation, connectivity, and plasticity

• Connects neural mechanisms to behavioral outcomes across development

Synaptic pruning

Part of neural development

Disused connections between nerve cells are eliminated

Neurogenesis & differentiation

Part of neural development

Forming specialized neurons

Connectivity

Part of neural development

Axon growth, synapse formation, circuit organization

Plasticity

Part of neural development

Experience refines and reorganizes circuits across development

Functional neural development

Development depends on both interactions with the environment and changes in connectivity within different brain regions

Interactive specialization

A theory proposing that cortical regions are not pre-programmed for specific functions

Brain regions progressively specialize through interaction and competition with other regions during development

Johnson, 2001

Examples of brain stimulation

1. Learn new habits/skills
2. Train your orientation
3. Learn a new language
4. Practice music
5. Don't let the work day linger, rest
6. Expand your vocabulary
7. Use the “wrong” hand
8. Learn to juggle
9. Play chess
10.Practice mindfulness

You are the architect of your own brain and you need to challenge your brain

Musical training

Collectively the existing literature tends to support the hypothesis that musical training can induce changes in cross-hemispheric connections

Significant differences frequently reported in various regions of the corpus callosum of musicians compared with non-musicians

Cross-hemispheric connections

• Enhanced sensory and motor integration

• Coordination between both sides of the body.

• Improved executive function –planning, impulse control, and decision-making

• Faster information processing

• Better working memory

• Greater cognitive flexibility

• Optimized language and communication

• Better emotional regulation

Connections across the left/right hemispheres of the brain

Mindfullness

We observed topological modifications in the brain, in the right hippocampus as compared to controls

Meditation might have a potential role as a preventive strategies to alzheimers.

Hippocampus

Role in memory processes and consolidation, and related to Alzheimer's disease

Healthy habits for our brain

• Aerobic → best technique to facilitate neurogenesis (30 min 5 days a week)

• Nutrition - Mediterranean diet and hypocaloric

• Stress - relaxation techniques and meditation

• Active mind - reading, learning, healthy social life

Epigenesis

Refers to changes in gene expression due to environmental factors

• AKA the environment can affect our behavior by influencing the way genes are functioning in our development

Does not alter the underlying DNA sequence

Environmental factors include diet, stress, toxins, lifestyle

Epigenetic examples

• Long-term high-sugar/high-fat diets can be associated with epigenetic changes in genes involved in insulin signaling and inflammation, which may contribute to insulin resistance and increased type 2 diabetes risk

• Childhood adversity has been associated with epigenetic marks in stress-response pathways, potentially influencing how the body responds to stress later in life

• Cross-generational influences on childhood anxiety disorders: pathways and mechanisms

Behavioral systems (parent behavior)

• Vicarious learning, social referencing, modeling

• Parenting style

• Parental responses to child anxiety symptoms

Biological mechanisms

• Prenatal environment

• The oxytocinergic system (specialized brain network that produces and uses the hormone oxytocin to regulate social bonding, emotional connection, and maternal care)

• Genetic and epigenetic transmission

Critical/sensitive

Specific window of time in early development during which the organism is especially receptive to particular environmental input

These experiences exert their greatest influence on the development of a given skill or capacity

• Critical period: the relevant experience must occur within the window; otherwise, the corresponding ability may fail to develop normally.

• Sensitive period: acquisition is optimal within the window but remains possible afterward, typically requiring greater effort

Interactionist view of nature v. nurture

Neither genes nor environment act in isolation

Most traits are polygenic and context-dependent

Developmental outcomes are probabilistic not predetermined

Reaction range

Genes set an upper and lower for a given trait, but the environment determines where (within that range) the individual actually falls

ex. extraversion and social interaction

Gene-environment interaction (GxE)

The same environment affects individuals differently depending on their genetic makeup

Gene-environment correlation (rGE)

Genes influence the environments to which a child is exposed, so that individuals partly shape or select their own developmental contexts

Evolutionary Theory

Darwin’s approach implied that behavior should be adaptive for the individual, as the genes that are selected are passed from parent to offspring

Evolutionary Psychology / Evolutionary Developmental Psychology

Present day thinking emotions and actions reflect our evolutionary history

Behaviors evaluated by fitness (survival & successful reproduction)

Cost-Benefit View

• Mutualistic (+/+): benefits A and B

• Selfish (+/−): benefits A, harms B

• Altruistic (−/+): harms A, benefits B

• Spiteful (−/−): harms both

For the good of the group/species

Kin Selection (Hamilton, 1964)

• Animals are more likely to aid genetic relatives

• Relatives share more genes than random group members

• Indirect gene transmission: helping kin also passes on shared genes

• Complements direct fitness (own offspring)

Reciprocal altruism (Trivers, 1971)

One individual will help another, at some smaller cost to itself, if it can expect similar help back from the other animal in the future

Monkeys and apes, recognize each other and could thus stop helping individuals who failed to reciprocate (‘cheats’).

Pairs of unrelated males would help each other in challenging a dominant male. Individuals that gave such help to a particular male often received help back from the same male

Ancestral environment

Ex. Children’s “sweet tooth” is unhealthy today (teeth/overall health) but adaptive in hunter–gatherer contexts, where rare, energy-dense foods (e.g., honey) were valuable

Limits of evolutionary approach

• Risk of naturalizing sex differences: Framing them as “inevitable” can legitimize stereotypes (e.g., Rose et al., 1984).

• May be post-hoc and hard to test empirically.

• Environmental plasticity: Development can be an adaptive response to context (e.g., pubertal timing influenced by stress).

• Learning, socialization, and structural factors often explain phenomena

Diathesis-stress

Model to describe variations in sensibility - vulnerability shows worse outcomes only under adversity

• Some individuals are more susceptible to adverse environments

• Diathesis = predisposition/susceptibility

• Dual-risk = negative outcome emerges when two risks co-occur (predisposition & adverse environment) Ex. Low MAOA activity + severe childhood maltreatment → developing antisocial behavior

Stressors during development

• Poor quality parenting/harsh or inconsistent caregiving

• Family adversity (conflict, low SES, instability)

• Stressful life events (loss, trauma, chronic stress)

Differential Susceptibility

Model to describe variations in sensibility - worse in bad & better in good environments

• Extends diathesis-stress

• Individuals vary in sensitivity: stronger reactions to both adversity and positive environments

• “For better and for worse” responsiveness

• People differ in how much environment shapes them

• Differential susceptibility explains both vulnerability and exceptional benefit

• Avoids pathologizing sensitivity

Belsky and Pluess (2009)

Vantage sensitivity

Model to describe variations in sensibility - better in good, no worse in bad

Vantage = position of advantage

Vantage sensitivity = some people benefit more from positive environments

Crucially: no corresponding disadvantage in negative environments (“bright side” of plasticity)

Contextualizing cognition

Cognitive development is context-dependent, not just an individual property (Cole, 1996)

Children’s thinking emerges via interaction with more knowledgable others

Cognition is linked to sociocultural activity, not only internal processes

Ex. Children assigned to take care of younger siblings (as in Kenya) learned more nurturant behavior

Zone of Proximal Development (ZPD)

Learning through guided participation → part of cognitive development

Prenatal Development

~9 months from conception: full-term ~ 38 weeks post conception

Three stages: germinal → embryonic → fetal

Early biology sets the ground plan: environment influences outcomes

Germinal Stage

Fertilization: sperm + ovum → zygote aka first mitotic divisions

Differentiation begins (cell fates start diverging)

Implantation in uterine wall (~day 7-14) = critical transition

High sensitivity to implantation failures (often unnoticed)

Embryonic Stage

Embryo ~ 1 in by week 8: head/limbs/hands/feet visible

Period of organogenesis → highest teratogenic vulnerability (to alcohol, drugs, infections..)

Fetal Stage

Skeletal ossification: cartilage → bone, refinements (hair, brows, nails)

Movement detectable by 3rd month → quickening obvious to mother ~4-5 months

By 7th month: breathe, cry, swallow, digest, excrete → prematurity survival possible

Final 8 weeks: size & fat gain, neural connectivity surgesF

Fetus traits

• Fetus is active/reactive; activity may prime neural & physical systems

• Familiarity with mother’s voice/smell → may facilitate attachment

Maternal voice studies

Newborns (2-4 days): more movement to taped maternal voice than to live maternal speech (novel pathway)

No clear fetal discrimination mother vs. unfamiliar when presented both via external tape

Prenatal risks

• preexisting health conditions

• pregnancy-related health conditions

• over 35 or under 17 years old

• lifestyle factors (substances, etc.)

Biospychosocial perspective

Genes set ranges + environments tune outcomes

Pregnancy sickness as adaptation (Profet, 1992)

• Nausea/vomiting peaks 6-8 weeks (max vulnerability window → teratogens)

• cross-cultural presence: linked to lower miscarriage rates in some studies

• Hypothesis: evolved avoidance of dietary toxins to protect embryo

The nature of birth

• humans “born early” in comparative terms → helpless neonate

• human brian ~ 50% adult by 1 year, ~75% by 3 yrs

Why are human babies so immature?

OD (Obstetric dilemma) & EGG (Energetics of gestation & growth)

OD (Obstetric Dilemma)

• Bipedalism reshapes pelvis/hips → birth canal constraint

• Bigger brains

• Evolutionary trade-off: locomotion efficiency vs. neonatal head size

EGG Hypothesis

• Maternal energy expenditure in late pregnancy: approaches roughly two times her baseline metabolic rate

• Extending gestation even 1 month may exceed maternal capactiy

• Pattern aligns with mammalian births: timing set by metabolic limits

Social implications of OD & EGG

• high infant dependence → cooperative care (“alloparenting”)

• Assistance needed during parturition and postnatal period

• Sources: fathers, partner, grandparents

Immediate Neonatal Transition

• Cord still pulsating → brief placental “cushion” while lungs inflate

• First breaths/cry = adaptation to extrauterine life

• Cord clamped/cut = placenta expelled within ~30 minutes

• Emotional peak: maternal relief/joy, family recognition, Apagar assessment follows

Apgar

Rapid Newborn Check → 5 indicators at 1 and 5 minutes

• Appearance

• Pulse

• Grimace → response to reflexes

• Activity

• Respiration

Scored 0-2 each, total 0-10, equal/more than 8 = healthy

Breastfeeding

Essential for survival in traditional societies

• Modern option: bottle-feeding

• Human milk = species-typical/well-matched to rapid postnatal brain growth

• Milk is mostly fat, protein, carbohydrates

• matches on-demand feeding in carrying societies

• Nursing frequency: the infant nurses almost continuously, so the milk doesn't need to be energy-dense

  • Lactose is easily metabolized and provides immediately available energy

• Hydration: constant contact allows for more watery milk that keeps the infant hydrated without needing large-volume feeds

Colostrum

• The first milk (first ~3 days): yellowish/blueish

• Rich in antibodies (early immune protection) + vitamin K (clotting)

Colostrum denial

• Higher infection risk

• Delayed milk “coming in” → breast engorgement, and increased mastitis

• Nipple-breast confusion and lower breastfeeding success

Birthweight

• Birthweight: normal ~ 3000-4000 g

• <1500g: more long-term psychological risk → high quality caregiving/stimulation can compensate

Protective psychosocial factors that can override perinatal risks

• Intact/happy family

• Alternate caregivers

• No prolonged early separations

• Sibling spacing

• Absence of poverty

• Kauai longitudinal study (Werner & Smith)

Attachment

• A lasting emotional bond btwn child and primary caregiver(s) characterized by proximity-seeking behaviors + using caregiver as secure base for exploration

• Enables protection, regulation, learning

• Mothers usually experience attachment to their babies before birth

• At 3 months, babies can be handed over to strangers BUT by 7 months, infants protest when separated from their mother aka first manifestation of separation anxiety

  • peaks at 14-18 months and then begins to decline

Temperment

• Infants vary: crying, activity, adaptability, mood → temperament

• Consistent patterns across months

• Predicts early self-regulation, sociability, and risk for adjustment problems

• Shaped by biology + caregiving (transactional model)

• Parenting quality can amplify or buffer risks, especially for difficult profiles

Temperament Profiles

Easy (40%): positive mood, regular, adaptable

Difficult (10%): negative mood, irregular, unadaptable

Slow-to-warm-up (15%)

How do babies differ in temperament? 9 dimensions

1. Activity level (movement during sleep/feeding/play)

2. Regularity (sleep, hunger, bowel rhythms)

3. Adaptability (ease of modifying initial responses)

4. Approach/Withdrawal (reaction to novelty: people/places/foods/toys)

5. Sensory threshold (stimulation needed to elicit response)

6. Intensity (energy of responses)

7. Mood (positive negative tone)

8. Distractibility (external stimuli interrupt ongoing activity)

9. Persistence/Attention span (duration on tasks despite obstacles)

Harlow’s Experiments

• Monkey with wire mom

• There is a difference between feeding and “care” → mother-child bond created as a result of intimate body contact and comfort + sense of security

• Healthier w cloth babies than wire babies, against pedagogic advice to limit body contact to avoid spoiling babies

Five Phases of Attachment Development

1. Phase 1 (0-3 months): Orientation without Discrimination

2. Phase 2 (3-7 months): Preferential Orientation

3. Phase 3 (7-24 months): Proximity Maintenance

4. Phase 4 (2-3 years): Goal-Corrected Partnership

5. Phase 5 (School age+): Attachment Lessening

Phase 1: Orientation without Discrimination

Age: 0-3 months approximately. The foundation phase of social development

• Baby orients and signals to anyone

• No discrimination between different people

• Responds equally to familiar and unfamiliar faces

• Indiscriminate smiling and vocalizing

• Similar comfort responses from anyone

Phase 2: Preferential Orientation

Age: 3-7 months approximately. The beginning of selective social responses

• Discriminates between people

• Selective comfort - calms faster with familiar people

• Preferential smiling with caregivers

• Subtle preferences - clear but gentle distinctions

Phase 3: Proximity Maintenance

Age: 7-24 months. Active proximity- seeking

• Locomotion - crawls/walks toward caregiver

• Separation protest

• Stranger fear

• Secure base use - explores while monitoring caregiver

Cognitive Prerequisites: cause-effect, object permanence

Phase 4: Goal-Corrected Partnership

Age: 2-3 years. Development of mutual consideration and negotiation

• Can wait when requested temporarily

• Understands explanations about caregiver's activities

• Takes caregiver's needs into account

• Engages in simple negotiations

Development of Reciprocity

Phase 5: Attachment Lessening

School age and beyond, from physical to psychological connection

• Less physical proximity - reduced need for constant closeness

• Relationship based on trust, affection, approval

• Internal working model - mental representation of relationship

• Greater independence - improved emotional self-regulation