[photo-3d] Infant stereopsis

[Abram Klooswyk <abram.klooswyk@xxxxxx>]

Bruce Springsteen 11 Oct 2000:
>Abram has indicated that there are plenty of good ways to 
>verify stereopsis in infants - what are they I wonder?

What I meant to say was that there are ways to predict in
adults if binocular training has a chance of being successful,
and that stereopsis has been established in babies and
infants from very early ages on, but I don't believe there
are many methods in the latter case.

When you really want to know more about the infant tests, 
why not try Pubmed, Nat Library of Medicine (USA) at: 
http://www.ncbi.nlm.nih.gov:80/entrez/query.fcgi
Just enter:   infant stereopsis random dot    and hit Go. 

One of the 303 papers is: 
J Pediatr Ophthalmol Strabismus 1998 Mar-Apr;35(2):86-90 
Infant random dot stereoacuity cards.   Birch EE, Salomao S 

Abstract: 
>>PURPOSE: The overall goal was to develop a simple test of 
random dot stereoacuity that can be used during the first 24 
months of life to measure sensory outcomes following treatment 
of ophthalmopediatric disorders, both in the context of 
clinical trials and in the context of clinical management. 
METHODS: A series of random dot stereoacuity test cards were 
constructed using vectographic vertical bar stimuli with 
crossed disparities ranging from 1735 to 45 sec. A two- 
alternative, forced-choice, preferential-looking test protocol 
was used to measure stereoacuity in 95 healthy term infants 
(173 tests) over the 1.5-to-24-month age range. Success rate, 
validity, and tolerance limits for normal performance as a 
function of age were evaluated. RESULTS: The success rate was 
high (158 of 173 tests; 91.3%). The maturation of random dot 
stereoacuity was similar to that measured in earlier lab-based 
preferential-looking and visual evoked potential protocols; 
few infants younger than 2 months of age demonstrated 
stereopsis although by 12 months, mean stereoacuity was 2.1 
log sec (120 sec). A further improvement to 1.7 log sec (56 
sec) was seen during months 18 to 24, consistent with data 
obtained in an earlier operant random dot protocol. Tolerance 
limits for normal ranged from approximately 1000 sec at 6 
months to 100 sec after 12 months. CONCLUSIONS: The infant 
random dot stereoacuity cards provide a simple, quick, and 
portable preferential-looking test of random dot stereoacuity 
for infants that has a high success rate and excellent 
concordance with stereoacuity outcomes from laboratory-based 
protocols.<<

"Preferential-looking test" is the method of choice when you 
don't want to attach electrodes to baby heads. It is
surprising
indeed that babies are interested at all in vertical bars.
The body parts of their mother don't resemble bars, I guess
:-)

Abram Klooswyk