MORE ON GESTATION AND HANDEDNESS
Use search engines of research papers, don’t assume, or depend on pop science news. There are hundreds of papers on the subject. Here are quotes from a variety of papers (9 papers):
“Preterm births lead to mixed handedness” (lateralization)
“Duration of gestation, specifically preterm birth (less than 37 weeks) is associated with less pronounced handedness – especially in girls”.
“Prenatal stress and (shorter) duration of gestation lead to mixed handedness” (Lateralization)
“Handedness is weakly heritable” (Handedness has a genetic component)”
“Studies suggest that the relationship between gestation and handedness by be influenced more by environmental factors than direct genetic links”
The most common factor across studies is maternal stress during pregnancy that limits the maturation of lateralization.
Similarly, preterm birth is associated with brain asymmetry – also a consequence of insufficient lateralization.
Similarly, internal asymmetry of internal development of the brain also can produce more serious results (ADHD, aggression, and ASD).
I can explain these subjects in extraordinary detail. HOwever, you should not assume that left handedness is indicative of anything OTHER than handedness.
Gestation is a complicated probabilistic process. 😉
CD
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