Prenatal Development & Newborns
1. How soon after conception does brain begin to form?
2. What are the 4 parts of the brain and the function of each?
3. What does nerogenesis mean?
4. What are the parts of a neuron and how do they communicate?
In-class Assignment 2
The purpose of this assignment is to help
you better understand the three phases of
prenatal development.
Teratogens

Agents that causes damage during prenatal
development; effect depends on…
– Dose level & length of exposure
– Genetic variability of mother & organism
– Multiple influences versus a single agent
– Age or whether organism is in a sensitive period
Figure 3.2: Sensitive periods in prenatal development
Teratogens

Agents that causes damage during prenatal
development; effect depends on…
– Dose level & length of exposure
– Genetic variability of mother & organism
– Multiple influences versus a single agent
– Age or whether organism is in a sensitive period
Effects may be delayed & psychological
 Includes **drugs, diseases, & environment**

1.
Alcohol

Statistics
–
–



25% of expectant mothers report drinking
55% for those who might become pregnant
Dose: < 1 glass/day is harmful
Sensitive period: Earliest months of pregnancy
Effects: Fetal Alcohol Syndrome (FAS)
–
Physical (facial) abnormalities
Fetal Alcohol Syndrome:
typical facial abnormalities
1.
Alcohol

Statistics
–
–



25% of expectant mothers report drinking
55% for those who might become pregnant
Dose: < 1 glass/day is harmful
Sensitive period: Earliest months of pregnancy
Effects: Fetal Alcohol Syndrome (FAS)
–
–
Physical (facial) abnormalities
Long-term mental retardation & overactivity
2.
Tobacco

Statistics
–



12% report smoking during pregnancy
Dose: more is worse; even 2nd-hand is bad
Sensitive period: throughout, but reversible
Effects:
–
–
–
Low birth weight
Behavioral disorders (ADD & ADHD?)
Long-term cognitive delays
Long-term cognitive effects of smoking
2.
Tobacco

Statistics
–



12% report smoking during pregnancy
Dose: more is worse; even 2nd-hand is bad
Sensitive period: throughout, but reversible
Effects:
–
–
–
Low birth weight (low nutrients)
Behavioral disorders (ADD & ADHD?) due to CO2
Long-term cognitive delays
3.
Cocaine

Statistics
–



1980s phenomenon; estimate 11%
Dose: unknown because of multiple influences
Sensitive period: throughout
Effects:
–
–
–
–
Born addicted & experience withdrawal
Shrill & piercing cry
Low birth weight
Long-term consequences?
Less so if environment changes
What are newborns capable of?
Newborn Capabilities: Reflexes

Inborn, automatic response to stimulation
Why?

Serves a function
– Survival of newborn (e.g., sucking)
– Motor development (e.g., stepping)
– Evolutionary, no longer important (e.g., Moro)
– Parent-newborn bonding
Reflexes
Reflexes
Newborn Capabilities: Reflexes

Inborn, automatic response to stimulation
Why?

Serves a function
– Survival of newborn (e.g., sucking)
– Motor development (e.g., stepping)
– Evolutionary, no longer important (e.g., Moro)
– Parent-newborn bonding
Most disappear at 6-months; voluntary control of behavior
Newborn Capabilities: Senses
Sense
Capability
Touch
Sensitive to touch, pain, & temperature
Taste
Distinguish between tastes, likes & dislikes
Smell
Can distinguish mother from other women
Hearing
Speech perception is better than adults
Prefer high-pitched, expressive sounds
Sight
Least mature, lack visual acuity, yet look for
stimulation
Dr. Suess Studies
Decasper & Fifer (1980)
Dr. Deuss Studies
Decasper & Fifer (1980)

Participants: 10 newborns (24 hours old)

Method
– Earphones on infants played tape-recording of mother
(and stranger) reading Dr. Suess story
– Pacifier in babies mouth monitored sucking

Results: newborns suck more in response to
mother’s voice
0.45
0.4
0.35
0.3
0.25
0.2
0.15
0.1
0.05
0
mother
stranger
Baseline
Mother
Baseline