Puberty Flashcards
(10 cards)
What is puberty?
Adenarche
Gonarche
Usually occurs between 6-20years
Females reach developmental stages quicker than males
What is Adenarche?
Usually starts 6-9 until 20
Hypothalamic-pituitary-adrenal axis- releases androgens
Results in skin changes, body occur and body hair
What is Gonarche?
Occurs between 10-15 years
Hypothamic-pituitay-gonadal-axis- releases estrogen and testosterone
Results in menstruation and voice changes
Reactivated from peri-natal exposure- lies dormant during childhood.
Hypothamic-pituitay-gonadal-axis:
Neurons in the hypothalamus begin to fire more rapidly, releasing gonadotropin release hormone, starts to stimulate the pituitary gland which release FHS and LH, then primary hormone estrogen and testosterone are released from the gonads.
Organisation-activation-hypothesis
Not all brain development occurs prenatally, the system is reactivated during A. There are 2 critical periods in which the brain is extremely sensitive to sex steroids.
Developmental Trajectories
Massive surges of estrogen and testosterone during puberty, Can predict the number of balloon explosions (Peper et al 2018) simply by looking at the bioavailable sex hormones, with a linear relationship. Also corresponds with self-reported risk-taking.
Op de Macks 2011: Testosterone levels correspond with increased ventral striatum activation in response to monetary rewards in A.
Puberty and Grey Matter
Peper et al 2009: Only those who had reached Tanner stage 2 had shown any GM decrease, especially in he mPFC- could be linked to the onset of puberty.
Blanton et al 2012- The amygdala and hippocampus which have high amounts of androgen receptors decrease in GM in relation to each Tanner stage, even after the effects of age are removed.
Puberty and White Matter
Herting et al 2012: WM increases throughout A, when the effects of age are removed it increases with each Tanner stage. Using bioavailable testosterone, the more testosterone found in boys was linked to strengthened connections in the corpus callosum.
Amaro et al 2018: WM has a stronger affinity to estorgen in the female brain, which is why it has an effect on the brain.
Perri et al 2008: In a male brain the increase in WM is steeper than that of females. Also found that the short androgen gene is more effective than the long androgen gene, those with more of the shorter gene have more bioavailable testosterone with higher WM calibre in the brain.
Puberty and Brain Function
Moore et al 2012: Face perception network activation is higher with each increasing Tanner stage, suggesting greater concentration of sex hormones links to FP.
Mareikova et al 2014: Higher levels of progesterone leads to greater brain response in females. Those on OC and mid-cycle, where hormones are highest had increased responses in FFA- linking to FP.
Measuring Puberty
Can be done in many different ways, most common is the Tanner Stages, this can be assessed by a cliinician, self report or questionnaire- can lead to variety of results.
Also hormone samples can be taken but invasive as hormones fluctuate throughout the day etc.
