Childhood Disorders

1. Childhood Disorders Psychology 2617

2. Introduction • To understand developmental disorders we first have to look at development of the nervous system • Basically it goes from head to tail and from near to far

4. Gross development • When a Mommy and a Daddy really like each other... • Primitive body at 15 days • Neural plate at about 3 weeks • Plate curls up, forms the neural groove, this becomes the neural tube • By 49 days pretty person like

6. Stem Cells • Neural stem cells line the neural tube • These divide quickly • Unlike adult stem cells, these guys divide and divide again, like well, like 'normal' (non neural) cells • Adult stem cells divide, but then one daughter cell dies! • Stem cells become neuroblasts or glioblasts

7. Stages in brain development • Cell birth • Migration • Differentiation • Maturation • Synaptogenesis • Cell death • mylenogenesis

8. Generation, migration and differentiation • Much easier to fix trauma if early on • Migration takes about oh 6 to 7 weeks • Then differentiation kicks in • Cells formed in a particular region differentiate into different types of neurons • Follow the radial glial road (very cool) • Layers of cortex develop from the inside out, as you would expect

9. Vulnerability and Plasticity • Teratogens (like booze for example) • Can cause agenisis or dysgenisis • Possibility for injury during birth too • Depending on the insult an immature brain may deal better than a mature one, though this varies more than originally thought

10. Some specific disorders • Hydrocephalus • Too much CSF • 27 per 100 000 • Pressure damages brain, usually pervasively • Sunting can help • Turner’s syndrome • Missing X • Low cognitive functioing • Less parietal metabolic activity

11. Acquired disorders • FAS • Growth retardation, facial anomalies • Hard to know how much alcohol is safe • FSS maybe too • Pervasive cognitive and behavioural deficits

12. Learning disabilities • Dyslexia • Seems to be a genetic cause • Slower flicker fusion • Magnocellular deficit perhaps • Could be due to planum temporale deficits • (symetric in dyslexic people)

13. Nonverbal Learning disability • Sort of the opposite of dyslexia • Seems it could be a question of integration • Right hemisphere, particularly parietal regions • Talk a lot, but don’t get the sort of social aspects of language

14. Pervasive developmental disorders • Autism • Poor (if any) linguistic development • Joint attention • Autistic aloneness? • Echolalia • Neologisms • Pretend play is abnormal • Book says 20 per 100 000, more like 300

15. autism • Hard to know what the cause is, though genetics do play a role • Hard to say what the problem is, is it cortex? HP? Amygdila? Other limbic areas? • Emotional perception and theory of mind

16. Putting it all together • Canalesthesia • Impaired affective assignment • Asociality • Extended selective attention

18. Outlook • Well, it depends on the severity • Some autistic people never even develop linguistic skills • Some autistic people end up in special ed programs • Some autistic people finish high school • Some get PhDs!

19. ADHD • More males than females • Can continue to adulthood • Maybe half of all psychiatric referrals! • Often occurs with other disorders such as ODD and CD • Often with anxiety or depression too

20. What is the cause? • Genetics • Abnormal corpus collossum? • Less communication • Frontal lobe issue? • Lack of asymmetry • Frontal basal ganglia? • Decreased blood flow

21. models • So what is the deal on this disorder? • Seems that attention cannot be focused • Most models suggest that some component of attention, or all the components, are messed up • Why do stimulants work? • Well, stimulants focus attention!

22. Conclusion • Some of this stuff is pretty sad • However, new techniques and diagnostic tools have allowed people with say Hydrocephalus and Autism to lead really fairly normal lives • Drug treatments have been effective for ADHD • There is lots of hope