Orientation-reversal VEP: comparison of phase and peak latencies in adults and infants.
Abstract
The peak latency of pattern-reversal (PR)-VEP has been found to develop rapidly, reaching the adult level around 15 weeks of age. However, the development of orientation-reversal (OR)-VEP, reflecting the specific spatial organization of cortical receptive fields, still remains unknown. OR-VEP was tested in 81 adults at 1-12 reversals/sec (r/s) and 94 infants (age 4-79 weeks) at 2-8r/s. OR data at 4r/s from an additional 123 infants (age 4.0-20.3 weeks) studied previously were also analyzed. In addition to peak transient latencies at 1-4r/s, latency values derived from the gradient of phase against temporal frequency in steady-state recording were also calculated. For both adults and infants, no significant latency differences in the initial positive peaks were found among the low reversal rates. The calculated latency was statistically longer than the transient latency in both groups. While the transient latency asymptoted to adult value of 102 ms at around 50 weeks of age, the calculated latency, unlike that for PR-VEP, showed little variation across the age span. The data suggest a dominant effect of transmission delay on the initial peak in infancy, which reduces with age. However, the overall timing of the cortical response...Continue Reading
References
Binocular interaction in normal vision studied by pattern-reversal visual evoked potential (PR-VEPS)
Citations
Related Concepts
Related Feeds
Brain developing: Influences & Outcomes
This feed focuses on influences that affect the developing brain including genetics, fetal development, prenatal care, and gene-environment interactions. Here is the latest research in this field.
Brain Injury & Trauma
brain injury after impact to the head is due to both immediate mechanical effects and delayed responses of neural tissues.