Research with Babies Flashcards
What are the typical methods for testing adults?
- Questionnaires
- Interviews
- Paper & pencil tasks
- Computer-based tests
- Test batteries (IQ)
- Experiments
What are the main stages of in utero?
- Germinal stage
- Embryonic stage (weeks 3–8)
- Foetal stage
What are some factors that influences the behaviour of the newborn?
Perceptual information available to the growing brain limited by environment (womb), so the input (Mother’s voice, foods ingested, stressors, etc.) influences the behaviour of the newborn
What are the different postnatal developmental stages?
- Neonatal (Neonatal < 1-mo)
- Infancy (Infancy/toddler < 2-yr)
- Childhood (Childhood < 12-yr)
- Adolescence (Adolescence late teens/early 20s)
- Adulthood (< Maturity)
How are studies conducted for smell and taste in utero/neonatal development?
Smell:
All of the necessary structures in place (nasal cavities, trigeminal system, neurons connect with olfactory bulb)
Much of the research animal-based (rats, rabbits, sheep)
Some from humans (Schaal, Marlier & Soussignan, 2000)
Taste:
Swallowing amniotic fluid at around 12 weeks (de Vries, Visser, & Prechtl, 1985)
Mennella, Jagnow & Beauchamp (2001) tested in whether experiences in final trimester impacted on weaning
Describe Schaal et al.’s (2000) study on anise.
Recruited expectant mothers who habitually consumed anise sweets/drinks (AC) & those who did not (nAC) - 12 per group
Some measures related to mothers & infants to show parity between two groups (gestational period, weight of infants at birth etc.)
Recorded consumption 15 days prior to expected term
Using diluted anethole, created anise odour similar to amniotic fluid
Within the first 8 postnatal hours (2.9 ± 1.9h, range 0.5-8h, colostrum?) tested neonates response to odour & retested at 4 days
Oro-facial response test were analysed blind by a coder who performed at a level of reliability >70% (Facial Action Coding System)
What are the findings in newborn senses of taste and smell?
- No. of –ve facial responses sig. at time 1 (<8hrs), not sig. at time 2 (4 days)
- Head orientation - sig. longer orientation at time 1 & 2.
Describe Mennella, Jagnow, and Beauchamp’s (2001) study on taste.
- Expectant mothers consumed 300ml of carrot juice or water 3 weeks during the last trimester of pregnancy & during the first 2 months of lactation.
- Group 1 drank carrot juice during pregnancy & water during lactation (infant only exposed during pregnancy)
- Group 2 drank water during pregnancy & carrot juice during lactation (only exposed during breastfeeding)
- Group 3 (Control) drank water during both pregnancy & lactation (no exposure)
- Approx. 4 weeks after initial weaning (with cereal) infants were videotaped tasting cereal prepared with water or carrot juice (counterbalanced)
- Immediately after each session, the mothers rated their infants’ enjoyment of the food on a 9-point scale (problem with this?) & eating recorded
- Infants who were exposed showed fewer neg. facial expressions to carrot compared to water & rated as enjoying carrot cereal more (compared to control)
- Basis for cultural differences in preferences?
Describe Mennella, Johnson, and Beauchamp (1995) study.
Abstract: Amniotic fluid samples were obtained from 10 pregnant women undergoing routine amniocentesis procedure. Approximately 45 min prior to the procedure, five of the women ingested placebo capsules, whereas the remaining five ingested capsules containing the essential oil of garlic. Randomly selected pairs of samples, one from a woman who ingested garlic and the other from a woman who ingested placebo capsules, were then evaluated by a sensory panel of adults. The odor of the amniotic fluid obtained from four of the five women who had ingested the garlic capsules was judged to be stronger or more like garlic than the paired samples collected from the women consuming placebo capsules. Thus, garlic ingestion by pregnant women significantly alters the odor of their amniotic fluid.
Found: showed that garlic flavour transmitted to amniotic fluid
The amniotic fluid is the protective liquid contained by the amniotic sac of a gravid amniote. This fluid serves as a cushion for the growing fetus, but also serves to facilitate the exchange of nutrients, water, and biochemical products between mother and fetus.
Describe the study conducted by Hepper, Wells, Dornan & Lynch (2012).
Hepper, Wells, Dornan & Lynch (2012) later showed that exposure to garlic during pregnancy (3-4 meals per week for 4 weeks) results in increased consumption of garlic potato gratin preference at 8/9 years
- 40 participants exposed, 33 at follow-up
- Parental reports & detailed food diaries at follow-up suggested little-no garlic exposure
- Test carried out twice (1 month apart), more consumption of gratin by those exposed prenatally
- Slightly odd way of carrying out measure & only 8% difference across a small sample. Enough to draw conclusions?
What did Steiner (1977) study suggest?
- Innate preference for sweet/dislike of bitter
- newborns reject the sour taste of citric acid as evidenced by facial grimacing
What does research say about exposure to tastes in infants ?
- Barring (except) bitter/sweet (umami), foods largely neutral & open to influence
- Exposure is the key to increasing acceptance (Birch et al. 1998; Birch & Marlin, 1982; Birch et al. 1987; Nicklaus et al. 2005; Pliner, 1982; Wardle et al. 2003; Wardle et al. 2003)
- Continues to contribute to cultural variances (Zellner, Garriga-Trillo, Rohm, Centeno & Parker, 1999)
- Exposure increases preference for a target food, for similar foods and reduces neophobia (Birch & Martin, 1982; Birch et al., 1987)
- Early exposure to different textures promotes acceptance of variations as the child ages (Foote & Marriott, 2003; Northstone et al., 2001)
Describe the Wardle, Herrera, Cooke, and Gibson (2003) study.
OBJECTIVE: The aim of this study was to evaluate two interventions (one reward-based and one exposure-based) for increasing children’s acceptance of an unfamiliar vegetable compared with a no-treatment control. It was predicted that the exposure condition would increase liking for, and consumption of, the vegetable relative to either the reward or control group.
DESIGN:
Using a randomized controlled design, participants were assigned to one of two intervention groups (exposure or reward) or to a no-treatment control condition, for a 2 week period. Liking for, and consumption of, red pepper was assessed before and after the treatment period.
SETTING:
The study was conducted in three primary schools in London.
SUBJECTS:
Parental consent was obtained for 49 out of a possible 72 children.
INTERVENTIONS:
Interventions comprised eight daily sessions during which participants in the exposure group were offered a taste of sweet red pepper and told that they could eat as much as they liked. Participants in the reward group were shown a sheet of cartoon stickers and told that they could choose one of them on condition that they ate at least one piece of the pepper.
RESULTS:
The exposure-based intervention significantly increased both liking (P=0.006) and consumption (P=0.03) compared with the control group. The outcome of the reward intervention was intermediate and did not differ significantly from the exposure or control conditions.
CONCLUSIONS:
Repeated exposure to the taste of unfamiliar foods is a promising strategy for promoting liking of previously rejected foods in children.
Is there a confounding variable in the Wardle, Herrera, Cooke, and Gibson (2003) study?
“we cannot be sure that reported associations are not the result of confounding between neophobia and pickiness.”
What are the influence of food neophobia and modelling on infants?
- Exposure has increased our preference or the foods we’ve eaten but then we start getting food neophobia - Avoidance of new foods
- Begins around the age of 18-24 months (Cooke et al., 2003)
- Culturally foods are similar, but can vary widely between cultures
- Said to be of evolutionary benefit - prevents ingestion of toxic foods
- Observed in animals
