1. The Biology of Disadvantage: Childhood Poverty,
Health, and Achievement
Nicole Hair
University of Wisconsin-Madison
Department of Economics and Institute for Research on Poverty
March 2, 2014

2. Talk Outline
Stylized facts about “disadvantage” and inequality
Consequences of childhood poverty for physical health,
behavior, early achievement and educational attainment
Theoretical framework for understanding how poverty might
affect children and families
Exploration of potential link between childhood poverty and
brain structure and development
Programs and policy responses aimed at mitigating influence
of poverty on children

3. What is Poverty?
Having little or no money or means of financial support
Federal government created a set of poverty thresholds in the
1960s
In 2012, the poverty threshold (FPL) for family of three was
$19,090 and for a family of four it was $23,050
US poverty rate 15% and WI poverty rate 11.4% in 2012
Alternative poverty measures are increasingly recognized as
important
US Census Supplemental Poverty Measure (SPM) takes into
account government benefits and necessary expenses like
taxes that are not in the official measure
2012 SPM poverty rate 16% slightly higher than official rate

9. Consequences of Childhood Poverty

10. Income gradient in health
Children (and Adults) in poorer households tend to have
poorer health
Relationship holds across numerous dimensions or indicators
of children’s health status

11. Case, Lubotsky & Paxson, Economic Status and Health in Childhood: The Origins of the Gradient, American Economic Review, vol. 92, iss. 5, pp. 1308-1334 (2002)
Case, Lubotsky & Paxson, Economic Status and Health in Childhood: The Origins of the
Gradient, American Economic Review, vol. 92, iss. 5, pp. 1308-1334 (2002)

13. Marginal Effects of Parental Income Level on Children
(6 to 17 years) Reported Being in Fair or Poor Health

14. Marginal Effects of Household Income Level on Adults’ Health
(Reported Being in Fair or Poor Health)

15. Currie and Lin, Chipping Away At Health: More On The Relationship Between Income And Child Health, Health Affairs
(2007) vol. 26 no. 2: 331-344
Adapted from: Currie and Lin, Chipping Away At Health: More On The Relationship Between Income And Child Health, Health Affairs (2007) vol. 26 no. 2: 331-344
Low-income children are in worse health than other children
Low-income children are more likely than other children to have chronic or
acute condition and are more likely to be limited by these conditions

16. Income Achievement Gap
Socioeconomic disparities in cognitive outcomes and academic
achievement have been well-documented
Childhood poverty associated with lower scores on
standardized tests, poorer grades in school, & less educational
attainment
(Brooks-Gunn, 1997; Haveman & Wolfe, 1995; Dahl & Lochner, 2012)
Observed ability gaps across SES groups open up at early ages
(Duncan et al., 1998; Cuhna et al., 2006)

17. Low income children enter school with higher levels of problem
behavior and these differences persist

18. Low income children enter school with lower levels of academic
skills and these differences persist

22. Bottom Line
Observed income gradient in health: children in poorer
households tend to have poorer health
Disparities in cognitive outcomes and academic achievement
also well-documented
Childhood poverty associated with lower scores on
standardized tests, poorer grades in school, & less educational
attainment

23. How does poverty lead to these
disparities??

24. Relatively little known about how early exposure to poverty
translated into deficits in cognition and achievement
Recent research efforts involving biomarkers and brain scans
attempt to gain insight into “black box” linking poverty to
poor health and deficits in achievement
Research on tie between poverty and anatomy of the
brain with Jamie Hanson, Seth Pollak, Barbara Wolfe and others
Goal of project: bring insight into what “causes” income achievement
gap
Potential neurobiological channel - explore whether brain structure/
development may serve as one bridge linking socioeconomic status to
achievement

25. SES, Environment & Brain Plasticity
Brain structure and development offer window into processes
linking poverty to deficits in cognition and academic achievement
Childhood poverty associated with inequities in both physical and
psychological environments (Evans, 2004)
↑ levels of life stress (family instability, violence) and exposure to
environmental toxins
↓ parental nurturance and cognitive stimulation in the home
Research with animals shows strong link between environment and brain
Environmental stimulation or enrichment, parental nurturance,
early life stress all affect brain growth and functioning
(Rosenzweig et al., 1978; Greenough et al., 1975, 1978; Zhang et al., 2004)
Small studies with humans suggest alterations in structure or functioning
(for review, Hackman & Hanson 2012)

27. Developed to aid in understanding brain maturation in
“healthy, typically-developing” infants, children, & adults
Size and scope unprecedented
Objective 1: children and adolescents 4 to 18 years
823 observations from 389 unique children
Objective 2: infants to age 4 years
200 observations from 81 unique children
Anatomic MRI scans, cognitive & behavioral assessments,
demographic characteristics
Scans “interpreted” using structural imaging techniques
(voxel based morphometry)

28. FIGURE 1: This figure shows example axial slices from a typical subject scanned at birth (left column), 2 (middle
column), and 4 years old (right column). T1 MRI, T2 MRI, and segmented gray matter (green) and white matter
(red) are provided.
Hanson JL, Hair N, Shen DG, Shi F, Gilmore JH, et al. (2013) Family Poverty Affects the Rate of Human Infant
Brain Growth. PLoS ONE 8(12)

29. A Bit of Background
Anatomy of the Brain
Brain can be divided into 2 hemispheres - right and left
3 types of materials or tissue
Gray matter - what fires in brain
White matter - wires of brain
Cerebrospinal fluid - jello like substance absorbs impact
Four lobes
Occipital - visual regions
Parietal - sensation and perception
Temporal - memory, emotion, auditory
Frontal - executive functions

31. Selecting Brain Regions of Interest
Cognitive neuroscience guides selection of brain regions of interest
Selection Criteria:
1. Critical for sustained attention, planning, & cognitive flexibility
Implications for learning and academic functioning
2. Protracted period of post-natal development
More likely to be vulnerable to environmental experience
3. Focus on gray matter tissue
Less heritable than other brain tissues (Gilmore et al., 2010)

32. Brain Regions of Interest
Total gray matter
processing information, execution of actions
Frontal lobe
problem solving, attentional control, complex learning
Temporal lobe
memory, language comprehension
(word identification, relation of heard sounds to letters of alphabet, attachment
of meaning to words)
Hippocampus
learning, long-term memory (portion of temporal lobe)

33. RESULTS: Infants
1. Infants from low-income families show delayed
trajectories of brain development
Used our estimated parameters to project total gray matter
volume trajectories for infants of varying economic
backgrounds based on the federal poverty level: 100
2. Results specific to gray matter critical for processing of
information and execution of actions
Infants from low-income families had lower volumes of gray
matter AND slower trajectories of growth during infancy and
early childhood
3. Delays tied to emergence of disruptive behavioral
problems among impoverished children
Use Child Behavior Checklist (CBCL); focus on childrens
internalizing and externalizing behaviors

34. Hanson JL, Hair N, Shen DG, Shi F, Gilmore JH, et al. (2013) Family Poverty Affects
the Rate of Human Infant Brain Growth. PLoS ONE 8(12)

35. Hanson JL, Hair N, Shen DG, Shi F, Gilmore JH, et al. (2013) Family Poverty Affects
the Rate of Human Infant Brain Growth. PLoS ONE 8(12)

36. Hanson JL, Hair N, Shen DG, Shi F, Gilmore JH, et al. (2013) Family Poverty Affects
the Rate of Human Infant Brain Growth. PLoS ONE 8(12)

37. RESULTS: Children and Adolescents
1. Examine potential neurobiological link between between
poverty and deficits in cognitive and achievement
outcomes
Establish a reference for normative brain development
Examine influence of poverty on regions of the brain critical for
scholastic achievement, adjusting for developmental norms
2. Childhood poverty associated with atypical development
in total gray matter, the frontal lobe, the temporal lobe,
and the hippocampus
Children from poor households display a maturational lag:
Regional volumes 5 to 8 percentage points below
developmental norms
3. Tie regions of the brain to performance on standardized
tests
Wechsler Abbreviated Scale of Intelligence (WASI)
Woodcock-Johnson III Tests of Achievement (WJ-III)

38. Normative Developmental Curve: Temporal Lobe Gray Matter

39. Normative Developmental Curve: Hippocampus Gray Matter

40. 80
85
90
95
100
105
RegionalVolumeasPercentageofAge-andSex-
SpecificNorm
Socioeconomic Status and Anatomic Brain Development
Low Income (<$25,000)
60
65
70
75
Total Gray Matter Frontal Lobe Temporal Lobe Hippocampus
RegionalVolumeasPercentageofAge
SpecificNorm
Express regional volumes as percentage of sex- and age-specific norm
Examine deviations from norm among low income children
Define household as low income or “poor” if reported household income
below $25,000 (approximately 133% of FPL for family of four over our
sample period)

41. 80
85
90
95
100
105
RegionalVolumeasPercentageofSex-andAge-
SpecificNorm
Socioeconomic Status and Anatomic Brain Development
Poor <$25,000 Near Poor $25,000-$35,000 High Income >$35,000
60
65
70
75
Total Gray Matter Frontal Lobe Temporal Lobe Hippocampus
RegionalVolumeasPercentageofSex
SpecificNorm

42. Takeaways: Childhood Poverty and the Brain
Poverty associated with atypical development
Concentrated among poorest children (below 133% FPL)
Regional volumes 5 to 8 percentage points below norms
Maturational lag begins to emerge in infancy
Each region tied to performance on indices of academic ability
and/or childhood disruptive behaviors
Consequences of atypical development for scholastic success
Skills important determinants for range of adult outcomes
Without interventions to mitigate influence of poverty,
children’s potential limited at young ages by this tie

48. Programs and Policy Responses
What works to lessen poverty’s influence on children?
Extended development of critical brain regions establishes
both greater vulnerability and opportunity
Development highly sensitive to changes in the environment
and nurturance - both negative and positive
Suggests interventions to remediate early environments may
have some success in altering link between poverty and
deficits in achievement

49. Income Support Programs
Earned Income Tax Credit
Significant increases in math and reading test scores among
children whose families qualified for the credit (Dahl and Lochner, 2012)
Casino revenues to American Indian families
Positive effects of income disbursements on high school
graduation and educational attainment (Akee et al, 2012)
Can we generalize to other types of programs?
Child tax credit, Supplemental Nutrition Assistance Program
(SNAP) increase families economic resources in similar ways.

50. Early Childhood Education (3 to 5 year olds)
Consistent evidence of short-run effects non-experimental
evidence of long-run benefits from several program models
i.e., Perry Preschool and Abecedarian
Shown to increase long-term school attainment and earnings
as well as reduce crime and the risk of adult poverty
(Duncan, Ludwig, and Magnuson, 2010)

51. Innovations and Uncertainty
Home visiting programs
Much to learn about how to promote positive parent-child
interactions
Approaches in very early childhood (birth-3)
How to balance income support and employment
Combining approaches
Where should building parents human capital fit in?