Brain Milestones
- Gestational Month 8
- Most neurons ever have
- Ultrasound shows REM (help with wiring potentially)
- Hearing is good, languafe learn begins
- brain wabves can be recorded
- 3 years
- brain 90-95% of adult size
- Synamptic density is 50% higher than adulthood
- Myelination at peak rate
- Hippocampus almost mature
- 4-11 years: Special prefrontal newtowrks
- Puberty max level of grey matter volume and cortical thickening.
- Largely driven by sex hormones
teen to mid-20s
- Largely driven by sex hormones
- grey matter begins to thin
- experience plays sig. role in process
Adolescene
- Cortical Growth and Thinning
- White matter grows in a linear fashion
- "Social brain" components are last to mature
The Adolescent Brian
- Fronta; :obes incompletly myelinated
- Connections between front and limbic system are immature
- decsions more emotional than rational
- bursto f sex hormone acitivty
- high levels of melatonin
- decreased levels of dopamine and serotonin
- Low serotonin linked with aggression and violence
The Adult Brain
- Mature at 25
- Mylenation complete
- No changes until 45
- weight and gray matter vol. dec. gradually
- fluid intelligence dec. by age 25
- many women not fullly menopausal until 50s, begins in 30s
- Mid-life adults need healthy habits
Health Brain Aging
- Multiple reserve factors
- Basic intelligence
- spiriotuality
- social relationships
- multilingualism
- Changes in same pathways impacted by dementia
- Posterior-anterior shift
- Shift of functions to anterior part of brain
- Weaker default mode network connections
- involve in self-reference thought
- reduce risk of depression in older adults
Adult neurogenesis
Most up to 18 months
- human begins diff. than other animals
- Skepticle of this occuring in humans
- Migration occurs throughout life
- hippocampus does not repair in humans
- The ventricular zone & The hippocampus might repair in animals