1. February 1, 2011 Julie A. Kable, Ph.D.
Ukraine Nutrition Project Update: Infant Neurodevelopment (Cardiac Orienting Responses)
February 1, 2011
Julie A. Kable, Ph.D.

2. Attentional Models of Infant Cognitive Development
Attention is a multi-faceted system rather than one thing
Models are driven by theory and data
Underlying belief that individuals strive to encode environmental stimuli, process it, and then generate adaptive responses

3. Predictive Validity Studies
Traditional Infant Tests (McCall, 1979)
Age in Infancy
Later Age 1-6 mo 7-12mo
At-Risk Sample
Info Processing Tasks
(Colombo, 1993)
Measure Correlation IQ (2-7)
Fixation Duration -.49
Novelty Preference +.49
Retention +.42
Reaction Time -.46
Rose & Wallace, IQ (11)
Novelty Preference .41

4. Problems with Information Processing Tasks
Information processing task have high attrition rates
Maintaining inter-rater reliability
These tests also have poor internal consistency
Data from the Fagan Test-2nd edition
Test Cronbach’s alpha
One .28
Two .38
Three .43
Four .48

5. O’Connor’s Work (1980, 1984) Primarily done to establish continuity
4-month HR responses to auditory stimuli were related (r=-.63) to 18-mo Bayley (1969) scores
4-month HR responses to same auditory stimuli were related (r=-.60) to 5-year Stanford Binet IQ

6. Why HR as an Index of Attention?
Has the potential to reduce the ambiguity of overt behavioral response
Sensitive to small and rapid changes needed to assess the different components of attention
ORs believed to adaptively gate oxygen to the brain to increase central processing of information
Attrition rates are lower (85- 95% completion)
Heart rate responses highly consistent (Cronbach’s alpha: )

7. Neurophysiological Encoding
Refers to using physiological responses in a learning context to index integrity and efficiency of the CNS
Can be used across stages of development and across species

8. Information Processing Tasks
Placing infants into a car seat
Mothers seated out of sight of infant
Attaching 3 physical sensors on the chest and lower abdomen to assess heart rate
Rests for a minimum of 1-minute
Started when child was awake & alert
30-sec baseline followed by stimuli

9. Protocol for Stimulus Presentation
Auditory stimuli:
Habituation: hertz pure tone pairs presented contiguously for 12 sec each
Dishabituation: hertz pure tone pairs presented contiguously for 12 sec each
Visual stimuli

10. Indices of Cardiac Orienting Responses
Measure
Direction of Optimal Responding
Average HR
Lower scores
Average HR Difference
Higher scores
Average Latency (Speed)
Average Slope
Lower scores (more negative slopes)
Average Peak

11. Average HR Trough over Trails-Phonemic Stimuli (/ba/-/da/

12. Cardiac Orienting Responses to Over Repeated Trials (tones and faces)

13. Cardiac Orienting Response to Phonemic Stimuli (/ba/-/da/)

14. OR in Average vs. Delayed/Intellectually Deficient Range at 4
OR in Average vs. Delayed/Intellectually Deficient Range at 4.5 years of age
Average
Delayed

16. Orienting Responses to Speech Stimuli (/ba/ -/da/) in Infants who Varied as a Function of Maternal Smoking Status

17. Orienting Responses to Speech Stimuli (/ba/ -/da/ in Infants who Varied as a Function of Maternal Smoking Status

18. Cardiac ORs Sizes by Design for Auditory Baseline
Alcohol Group
No Supplements
PNV
PNV +Choline
Exposed 16 13 14
Non-exposed 25 12 7
Minimum preferred is 10 per cell

19. Percentage with ORs on Habituation Trials

20. Frequency of ORs by Group Status on Auditory Dishabituation Trials
T3 Trend in nonexposed for an intervention effect
Visual trials not significant but a trend for an intervention effect in the non-exposed samples
T1-Exposed, no intervention-lower than nonexposed, no intervention (X=4.4, p < .04)
Significant intervention effect in exposed groups (T1-χ=7.7, p < .02; T3- χ -8.3, p < .02)
Among PNV, exposed less likely than the nonexposed (T3-χ=4.7, p < .03)

21. Baseline HR Group Differences
Auditory stimulus
Significant intervention effect (F (2, 81)=5.3, p < .007). PNV+choline had higher overall HR
Significant interaction between exposure group status and intervention effect (F (2, 81)=3.1, p < .05). The above effect was strongest in the non- exposed groups
Visual stimulus
Exposure group status* intervention effect (F (2, 78)=3.1, p < .05). Same as above
Differences values (Baseline HR-OR HR)

22. Design Analysis of Auditory Habituation Data
Repeated measures ANOVA
Significant linear trend for trial (F (1, 80)=4.4, p < .04)-ORs diminish over time
Exposure by intervention by trial effect (F (4, 160)-2.6, p < .04). Among exposed, greater magnitude of deceleration relative to those who received no micronutrients or PNV alone on trials 2 and 3.

23. Average HR Difference by Trial for Each Group on Auditory Habituation Trials

24. Other findings
Auditory Dishabituation Trials-trend for trial effect, intervention effect (F (2,71-3.7, p < .03) with the greatest deceleration in PNV+choline, trend for exposure group status
Visual Habituation Trials-trial*intervention group effect trend T1& T2-PNV+choline had a greater magnitude of response and T3 PNV had greater magnitude of response than those without intervention
Visual Dishabituation Trials-trend for trial effect, trend for exposure group status* trial

25. Summary
Data represent a preliminary analysis of the cardiac ORs relative to the exposure group by intervention status.
Results are promising but need larger n within each cell to improve power to detect effects, particularly the interactions effects
Some evidence that choline supplementation improves neurophysiological encoding but maybe for both exposure status groups.