2: Biological Beginnings + Prenatal Development Flashcards
Evolutionary psych
definition
Branch of psychology that emphasizes the importance of adaptation, reproduction, and “survival of the fittest” in shaping behaviour
Chromosomes:
what are they? how many in one cell?
wound up DNA strands
46 chromosomes, 23 from each parent
egg and sperm chromosomes
egg: 23 chromosomes, including one X
sperm: 23 chromosomes, including an X OR Y
5 chromosomal abnormalities
name + chromosome difference
All syndromes
Down: extra ch. 21 (trisomy 21)
Klinefelter: extra X (XXY)
Fragile X: abnormal X ch.
Turner: missing X ch. (XO)
XYY: extra Y ch.
2 Gene linked abnormalities
name + effects
Phenylketonuria (PKU): cannot metabolize phenylanine, if it is consumed it builds up in the child causing intellectual disability and hyperactivity
Sickle-cell anemia: impaired red blood cells (cannot carry enough oxygen)
genotype environment correlations
name + meaning
passive: occurs because genetic relatives shape the environment of the child (eg: athlete parents provide environment for athletic child)
evocative: child’s genes elicit certain environment (eg: child is highly energetic, teachers respond by finding them disruptive in class)
active: child seeks out environments they find compatible and stimulating, related to their genotype (eg: active child enjoys running, decides to join soccer team)
heredity environment correlation view vs epigenetic view
HECV: inheredited genes impact environment in a unidirectional manner
epigenetic: heredity influences environment and vice versa (eg: skink lizards exposed to snakes that survive, have offspring with better survival traits)
Grooming in rats study
- grooming pattern (high or low) of mother is replicated by children
- children raised by mother with opposite genotype will replicate grooming pattern (LG genotype raised by HG mother become HG mothers and vice versa)
- linked to DNA methylation higher DNA methylation –> less cortisol receptors –> poor stress regulation
- ## grooming linked to demethylation meaning better stress regulation
conduct disorder
- highly linked to childhood maltreatment (especially severe)
- behaviours must emerge before 10yrs for diagnosis
brain development steps
- 24d form neural tube flat neural plate folds into tube
- 28w neurogenesis neurons form in neural tube
- 7mo. migration neurons move to permanent locations
- lifelong differentiation neurons grow, produce dendrites and axons, specialize, synapses form, axons are myelinated
- lifelong cell & synaptic pruning removal of low use neurons and synapses –> increases efficiency
teratogens
- agent that can potentially cause a birth defect which harms cognitive or behavioural outcomes
- harm is most likely earlier in development
- different parts of the body are susceptible to teratogens at different times
teratogen examples and basics
thalidomide: prescribed in 1950s, causes birth defects
alcohol: fetal alcohol syndrome –> facial features and cognitive deficits (4oz/week)
nicotine: preterm births, low birth weight, miscarriage, respiratory problems, shorter telomere length
vaping: insufficient data, deficiencies observed in animal adolescents
prenatal hearing
- developing fetus can hear sounds outside the womb through fluid filled ears
- child may have predisposition for learning the language they heard prenatally
dr. suess study
suckling study showecd preference for mother’s voice reading dr. suess if they read it prenatally
carrot juice study
regardless of whether the mother drank carrot juice before or just after birth, infants preferred carrot juice 6mo. later
prenatal facial patterns in response to taste
- facial expressions (as measured through muscle activation and images) change when exposed to bitter or sweet tastes
