Question 1

VA timeline

Accepted Answer

1 week = visual function with flash VEP 1 month = spatial acuity with pattern VEP 6 months = pattern VEP shown to demonstrate 20/20 3-4 years = subjective methods show 20/20

Question 2

Spatial acuity by forced choice preferential looking - 1 mo - 1 yr - 3-4 yrs

Accepted Answer

1mo: 20/600-1200 1yr: 20/50-60 3-4yr: 20/20

Question 3

Infant OKN

Accepted Answer

Asymmetric until 3-5mo (incomplete cortical development) - normal temp to nasal (“ToNs of movement”) - abnorm nasal to temp

Question 4

Development of vernier and recognition acuity

Accepted Answer

V: aka hyperacuity - develops slowly (worse than spatial until 4mo) - at 4 mo develops rapidly -> better than spatial - adult levels at 6-8 years R: doesn’t develop until 2-3 years

Question 5

Why VA is poor until 3-5 yo (3)

Accepted Answer

Foveal cone PRs shorter + wider than adults until 4yo Incomplete myelination of visual pathway -most by 4-6mo, all by 2 years Under-developed visual cortex until 6mo -continues well into childhood

Question 6

Refractive error - newborns - 10 weeks - 20 weeks - 1 year

Accepted Answer

+2.00 ± 0.75 Axial length 16mm 10 wk: plano to +4 20 wk: plano to +3 1 yr: +0.50 to +1.00 -stable into teens

Question 7

Emmetropization - greatest degree when - when doesn’t happen

Accepted Answer

First 2 years Extreme REs: > +5.00 or -4.50

Question 8

Astigmatism in newborns

Accepted Answer

In 50% Avg 2D ATR at 6mo Decr to 0.50 or less by 2 years

Question 9

Development of accommodation and vergences

Accepted Answer

A: capable in few weeks, adult levels 3-4mo

V: capable in few weeks

1 mo: consistent divergence
2 mo: consistent convergence, accomm and conv become linked
6 mo: adult levels

By 6 mo, all eye movements have usually reached adult levels

Question 10

Development of saccades and pursuits

Accepted Answer

S: make one large saccade instead of many small by 6 mo (immature cortical system)

P: series of small saccades until 8 weeks, normal pursuits by 4mo

By 6 mo, all eye movements have usually reached adult levels

Question 11

Development of stereopsis

Accepted Answer

Appears suddenly at 3-5mo Adult levels 4-6mo 1min of arc by 24mo

Question 12

Development of contrast sensitivity

Accepted Answer

Peak at 4 years Overall adult levels 7-9 years

Question 13

Development of color vision

Accepted Answer

Newborn: discern between red + achromatic - photopic = adults - scotopic = adult 4-7 mo 3-4mo: hue discrimination adult levels

Question 14

Ocular dominance columns

Accepted Answer

``` 1 = only contralateral 4 = equal both eyes (majority of all cells are binocular) 7 = only ipsilateral ``` ``` Dip in center (less both eyes) can indicate alternating strabismus Critical period (esp first 2 years) ```

Question 15

Normal changes with aging - VA - refractive error - contrast sensitivity

Accepted Answer

VA: - high contrast stable until 65-70 years - low contrast, low illumination decr 50-80 RE: incr ATR, hyperopia CS: stable until 65

Psychology Flashcards

(25 cards)