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Advanced Developmental
Psychology
PSY 620PMarch 17, 2015
Discussion Leader Assignments
Socialization Processes
Parent-child relationships Peer relationships School and community influences
2013
Background: Institutional Rearing and Development
Children raised in institutions: More likely to have deficits in cognitive function Deficits in language production and comprehension Elevated rates of ADHD Difficulties with social functioning
Explanation: Deprived environment does not provide adequate
experience for proper brain development So expect to see structural and functional neural
abnormalities Institutionalization has been associated with variety of
differences in neural structure, differs between studies
Method
General: 79 participants (subsample of BEIP study)– (136 total in sample) Ages 8-11 years Bucharest Early Intervention Project (Bucharest, Romania) MRI and EEG on longitudinal study participants
Conditions (3): Only RCT of foster care for institutionalized children Typically developing children in Romania (NIG) n=20 Children exposed to institutionalized rearing (CAUG) n=29 Children previously exposed to institutional rearing but then randomized
to high-quality foster care intervention (FCG) n=25
Analyses Regression analyses used to examine differences in structural and
functional neural correlates of institutionalization during development Mediation analysis used to further delineate proposed relationships
Previous Findings - BEIP
EEG Studies (BEIP) EEG at
▪ Study entry, M= 22 mo▪ 30 mo▪ 42 mo ▪ 8 years
Through typical development, relative increase in α-frequencies ▪ Seen globally (indicates structural changes)▪ At study entry, those exposed to institution had reduced α-power▪ At age 8, children placed in foster care younger “caught up” more in
α-power
Results: Total Cortical Grey Matter
• Relative reduction in grey matter volume in children exposed to institution compared to unexposed children
• No significant difference between those placed in foster care and those kept in institution
Results: Total Cortical White Matter
• Suggests neuroplasticity of white matter following environmental deprivation
• Similar pattern for Posterior Corpus Callosum (CC)
• BUT no significant difference between those placed in foster care and those kept in institution
Results: Mediation Model
CAUG group membership(Environmentally deprived
condition)
Total Cortical White Matter
Volume(Effect on
brain structure)
Power in α-frequency
Band(Effect on brain
function)
Discussion Questions
What do these results say about the effect of institutionalization on development?
What kinds of programs might help these kids and when?
What other types of assessments and at what time points might add to these results?
Which is better?
Messinger
Ordinary Variations in Maternal Caregiving Influence Human Infants’ Stress Reactivity
(Hane & Fox, 2006)
Rubenstein
Background
Previous research suggests that early human caregiving may affect the development of the systems that underlie stress reactivity.
Rubenstein
Goal
Compare infants based on the quality of Maternal Caregiving Behavior (MCB; low vs. high)
Hypothesis: Infants who experienced low-quality MCB would exhibit a pattern of right frontal EEG asymmetry, higher fearfulness, and less sociability than infants who experienced high-quality MCB.
Rubenstein
Method
4 months [lab, N = 779]• Reactions to novelty • Creation of temperament groups
9 months [lab, N = 185]• EEG data collected• Infant fearful response• Infant positive joint attention
9 months + 2 weeks [home, N = 185]• Videotaped mother-infant interactions
• Quality of MCB• Quality of infant affect during mother-infant interactions
Rubenstein
Results
Infant measures obtained at 9 months (lab & home)
Temperament group
Maternal-caregiving-behavior groupLow quality High quality
Control 17 8
Positively reactive 10 10
Negatively reactive 7 7
No sig sex differences
Creation of Caregiving Groups (Low and High Quality)
Rubenstein
Results
• Low-quality MCB group sig more likely to exhibit a pattern of right frontal EEG asymmetry and fearfulness
• Low-quality MCB group sig less likely to manifest positive joint attention
MCB and stress reactivity (frontal EEG asymmetry, fearfulness, and sociability)
Differences in stress reactivity a function of temperament groups? Computed series of one-way univariate ANOVAs and temperament group had no sig main effects on these results.
Rubenstein
Results
• Low-quality MCB group expressed sig more negative affect while in care of mothers
• Degree of positive affect did not differ between the groups
MCB and infant affect during interaction
Differences in infant affect during caregiving a function of temperament? No.
Rubenstein
Conclusions
Results suggest that ordinary variations in MCB may influence the expression of neural systems involved in stress reactivity in human infants.
1. Infants receiving low-quality MCB showed more fearfulness, less positive joint attention, and greater right frontal EEG asymmetry than infants receiving high-quality MCB.
2. Group differences in stress reactivity were not a result of measured infant temperament.
3. Infants receiving low-quality MCB experienced more negative affect during caregiving activities than did infants receiving high-quality MCB.
Rubenstein
Discussion Questions
• The study divided infants into two extreme groups: low quality and high quality MCB groups. Could this division affect the results?
• The infants in this sample represent a middle-class, low-risk demographic group, and the measure of MCB captures ordinary variations in MCB (not extreme instances of deprivation, abuse, or neglect). Would these ordinary variations in MCB have the same effect in high-risk populations?
• Quality of infant affect was rated as either positive or negative. Are there any issues with this coding strategy?
Rubenstein
Messinger 28
Introduction to Attachment
PSY344
Messinger 29
Attachment’s Function/Goal:Keeping Caregivers Close
Messinger 30
Environment of evolutionary adaptiveness
Protection from predators and . . . conspecifics
Messinger 31
Attachment system
Inherent motivation Organization of different behaviors
Doesn’t matter how you get to caregiver With single function In a goal-corrected manner
Attachment as an organizational construct
Messinger 32
Multiple attachments
Infants form attachments to many caregivers
A hierarchy is assumed In which infant turns first to primary
caregiver
Role of fathers
What forms the basis for attachment relationships?
How do we know that attachment represents an “emotional” bond?
Primary Drive Reduction Theory Preference based simply by having
primary needs (i.e., hunger) met?
What forms the basis for attachment relationships? (cont)
Harlow’s studies and the rejection of “drive reduction” explanations Spitz (1946) noticed that infants in
orphanages (who were adequately nourished but had no loving attention) did very poorly
Harlow’s surrogate mother studies examined relative influence of feeding vs. contact/comfort on attachment
Harlow’s Surrogate Mother Studies
Bale-wire meshvs.Terry cloth
Each could be equipped with feedingnipple
Test preference duringtimes of stress
Harlow’s Surrogate Mother Studies (cont)
From Blum (2003)
Messinger 38
Time is spent on cloth mothers
Both wire and cloth fed spend most of their time on cloth surrogate mother Regardless of
which “mother” fed you
Measuring Attachment
Ainsworth’s (1978) Strange Situation Seven episodes increasing amount of stress (e.g.,
unfamiliar environment, unfamiliar adult, brief separation from parent)
Of interest is how attachment behaviors are organized around parent
Attachment classification based primarily on reunion behaviors
See example at:http://www.youtube.com/watch?v=QTsewNrHUHU
http://www.youtube.com/watch?v=DH1m_ZMO7GU
Attachment Classifications Secure Attachment (Type B; 65% in NA)
Ambivalent/Insecure-Resistant (Type C, 15% in NA)
Insecure/Avoidant (Type A, 20% in NA)
Disorganized (Type D, very rare)
Basis for Individual Differences?
Sensitive/responsive caregiving Nurturant Attentive Nonrestrictive Synchronous Predictable
Predictive Validity of Attachment Styles in Infancy
Secure attachment in infancy associated with a variety of positive developmental outcomes including:
Why? What are potential mechanisms?
Messinger 44
Background
What is infant attachment measuring? Caregiver responsiveness vs. child temperament Infant emotional reactivity vs. regulation
One possible theory:
Insecure Avoidant
Insecure Resistant
SecureB1, B2 vs B3,
B4
Distress Reactivity
Low High
5HTTLPR(Serotonin-transporter-linked polymorphic region)
Molecular genetics = objective measure of distress reactivity and attachment
Common genetic variant Short (S) allele – Negative affect,
Emotional Disorders, Reduced Serotonin, Increased Amygdala Activity
Long allele variant (LG)— same as S allele
Long allele noncarriers (LA)
Goals
Determine unique contributions of caregiver quality and genetic variation (5HTTPLR) on infant attachment at 12 and 18 months
Caregiver quality will predict secure vs insecure More responsive mothers lead to secure babies
5HTTPLR variation will predict reactivity across security S and LG alleles will be more reactive than LA
155 infants and their mothers Maternal Responsiveness at 6m
▪ Home-interactions Attachment Classification at 12m and 18m
▪ Strange Situation Genetics at 32 years
Predicting Security and Distress Reactivity
Questions
If attachment and temperament are stable constructs, then why aren’t the results the same at 12 and 18 months?
At the beginning of the article, they laid out the debate that attachment is either based on maternal responsivity or infant temperament. Which do you think is more important?
Messinger 57
Sensitivity Studies Only
Perceive signals accurately and respond promptly and appropriately 22% (r = .22), 7,223 infants in 123
comparisons Original Ainsworth subscale
24% (r = .24), 837 infants in subset of 16 studies
Socioeconomic class is a moderator▪ Middle (r = .27); lower (r = .15)
What is the role of 5HTTLPR in G X E interactions? Should the 5HTTLPR genotype be considered a marker of vulnerability of susceptibility?
Background
Diathesis-stress model
Background
Differential-susceptibility model
Method
Meta-analysis o Searched for “serotonin” or “5HTT” and “human”o Studies with behavioral, psychiatric, or developmental outcomes in
children under 18
Extracted 77 effect sizes on 9361 subjects from 30 reportso 41 concerned vulnerability (e.g., bullying and emotional problems)o 36 focused on the “bright side” (e.g., high-quality family functioning
and alcohol)
Examined 5 moderatorso Ageo Ethnicityo Single-necleotide polymorphism (SNP)o Method of assessing environmento Method of assessing outcomes
Results
ss/sl carriers are more vulnerable to environmental adversity than ll carriers
ss/sl carriers did not benefit significantly more from positive environments than ll carriers
Age, SNP, and methods were not significant moderators
However, ethnicity was a significant moderator of the association between positive environment and positive outcomes for ll carriers
Results
Discussion Questions
Belsky & Pluess (2009)
Differential Sensitivity Model
How different from traditional diathesis-stress model?
How do study designs differ based on these models? Range of environments? Range of psychological and behavioral
outcomes?
Temperament & Parenting
Kochanska et al., 2007
Bradley & Corwyn, 2008
Temperament & Out of home Care
Pluess & Belsky, 2010
Genetics & Early Adversity
Taylor et al., 2006
Gene-Endoenvironment Interaction
DRD4 - Long Allele Novelty/Sensation Seeking Attention Problems/Aggression Susceptibility to Parenting
EEG Asymmetry Left Frontal – “Easy”
Temperament Right Frontal – “Negative
Reactive” Temperament Schmidt, Fox, Perez-Edgar &
Hamer (2009)
Mattson
"Long" versions of polymorphisms are the alleles with 6 to 10 repeats. 7R appears to react less strongly to
dopamine molecules.[8]http://en.wikipedia.org/wiki/Dopamine_receptor_D4
Group Differences
Mattson
DRD4 by Asymmetry Susceptibility to
Asymmetry▪ Soothability▪ Attention Difficulties
▪ Asymmetry unrelated to DRD4
▪ Complex Gene-Gene Interaction?
Genes influence relation between parenting and temperament• 18-21 month olds• DRD4 48 (7-repeat
allele) “long”• Allele increased
sensitivity to environmental factors such as parenting.
• Lower quality parenting higher sensation seeking.
• Higher quality lower sensation seeking
Parenting quality interacts with genetic variation in dopamine receptor D4 to influence temperament in early childhood Sheese BE, et al. Dev Psychopathol 2007 19(4):1039-46
Messinger & Henderson 83
Belsky & Pluess (2009)
Future Directions Importance of assessing
▪ Environmental adversity AND environmental support▪ Negative outcomes AND adaptive/positive outcomes
Consideration of mediating mechanisms▪ Physiological reactivity and thresholds to respond▪ Attention biases related to reactivity
Plasticity as ▪ Gradient?▪ Domain specific?