adolescent development Flashcards
what is puberty characterised by?
maturation of all functions
what is the difference between male and female reproductive function timescales?
males persists throughout life whereas womens ceases at menopause
age of onset of puberty ranges from?
8-15 years
what are early maturing girls at higher risk of?
child parent conflict, teasing, early sexual activity, eating disorders, early substance use
what is more associated for early maturing boys?
more socially poised, more popular, issues with rebellion,, show less empathy
immaturity is at the level of the brain. what brain structures?
limbic structures and hypothalamus
why is the reproductive function so late to mature?
because immaturity is at the level of the hypothalamus and limbic-hypothalamic pathways
how do we know that the limbic-hypothalamic system is responsible for the immaturity of the reproductive system before puberty?
immature gonads translated into an adult animal will mature immediately and demonstrate a normal reproductive system, the pituitary take from a prepubertal animal > adult animal will regulate a normal reproductive function, lesions/trauma of the hypothalamus and limbic system will prevent prepubertal animal to develop a normal reproductive function
in children what is the status of gonadal function?
testies/overies and secondary male and female organs, low levels of sex organs, low levels of GnRH and FSH/LH
GnRH is released from the _________
hypothalamus
FSH and LH are released from the ___________
anterior pituitary gland
what is the trigger of puberty?
production of gonadotrophin releasing hormone (GnRH)
what is the process where appropriate sex hormones (testosterone, oestrogen) are released?
hypothalamus releases GnRH > stimulates pituitary gland > releases LH and FSH > these hormones signal male and female sex hormones to be released
what are the effects of puberty when sex hormones are released?
growth spurt, primary and secondary sex characteristics
what is the difference between primary and secondary sex characteristics?
primary are directly involved in reproduction, whereas secondary are not necessary for reproduction
give some examples of secondary sex characteristics
odour, acne, breast development, hair, voice changes
what contribute to the conflict, moodiness and sexual urges of adolescents?
hormones (but not only cause_ > social and cultural reactions to visible body changes play a role
what factors does the age of onset of puberty depend on?
gender (girls ahead), genes, ethnicity, weight, stress
the lymphoid system _____ in she which makes teens less susceptible to asthma and colds
decreases
what is lack of sleep in teens associated with?
higher risk of mood disorder, driving problems, academic achievement
what are the ways to study brain changes through development?
structural and functional MRI, diffusion tensor imaging
what brain regions have the most dramatic changes during adolescence?
prefrontal and subcortical regions
what happens to the density of grey and white matter during adolescence?
Grey matter decreases (cortex, parietal areas, basal ganglia), white matter increases (due to more myelination)
why do big changes occur in the prefrontal cortex?
proliferation and synaptic pruning processes
which brain regions mature earliest?
those with primary functions such as motor and sensory systems
what areas did studies using MRI based measures show to be where cortical grey matter loss occurs earliest and latest?
earliest = primary sensorimotor areas, latest = dorsolateral prefrontal and lateral temporal corticles
in contrast to grey matter, white matter increases in a _____ pattern and increases throughout development well into adulthood
linear
why does white matter increase in adolescents?
reflects ongoing myelination of axons by oligodendrocytes enhancing neuronal conduction and communication
what did Goddings et al (2014) find in their longitudinal sample of 711 MRI scans from 275 people age 7-20 yrs
amygdala and hippocampus increase in size with puberty and age, other parts of basal ganglia reduce in size > these findings suggest a significant role for puberty in structural brain development, found sex differences
are mood disorders higher in males or females?
females
do men or women have earlier onset times for schizophrenia?
men
