Document Detail


Infant temporal contrast sensitivity functions (tCSFs) mature earlier for luminance than for chromatic stimuli: evidence for precocious magnocellular development?
MedLine Citation:
PMID:  10615492     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
In order to investigate the development of luminance and chromatic temporal contrast sensitivity functions (tCSFs), we obtained chromatic and luminance contrast thresholds from individual 3- and 4-month old infants, and compared them to previously obtained functions in adults. Stimuli were moving sinusoidal gratings of 0.27 cyc/deg, presented at one of five temporal frequencies: 1.0, 2.1, 4.2, 9.4 or 19 Hz (corresponding speeds: 3.8, 7.7, 15, 34, 69 deg/s). Previous studies, including our own, have shown that adult tCSFs are bandpass for luminance stimuli (peaking at 5-10 Hz), yet lowpass for chromatic stimuli (sensitivity falling at > 2 Hz), and that the two functions cross one another near 4-5 Hz when plotted in terms of cone contrast. In the present study, we find that the shapes and peaks of the luminance tCSF in both 3- and 4-months-olds appear quite similar to those of adults. By contrast, chromatic tCSFs in infants are markedly different from those of adults. In agreement with our earlier report (Dobkins, K. R., Lia, B., & Teller, D. Y. (1997). Vision Research, 37(19), 2699-2716), the chromatic function in 3-month-olds is rather flat, lacking the sharp high temporal frequency fall-off characteristic of the adult function. In addition, the luminance tCSF in 3-month-olds is elevated above the chromatic tCSF, and the two functions do not exhibit an adult-like cross-over within the range of temporal frequencies tested. By 4 months of age, substantial development of chromatic contrast sensitivity takes place at the lowest temporal frequencies. Although still immature, the 4-month-old chromatic tCSF has begun to adopt a more adult-like shape. In addition, similar to adults, luminance and chromatic tCSFs in 4-month-olds cross one another near 5 Hz. In adults, magnocellular (M) and parvocellular (P) pathways are thought to underlie the bandpass luminance and lowpass chromatic tCSF, respectively (e.g. Lee, B. B., Pokorny, J., Smith, V. C., Martin, P. R., & Valberg, A. (1990). Journal of the Optical Society of America (a), 7(12), 2223-2236). Based on this correspondence between psychophysical and neural responses in adults, our results suggest that the relatively slow development of the chromatic tCSF in infants may reflect immature chromatic responses in the P pathway and/or reliance on chromatic responses originating in the M pathway.
Authors:
K R Dobkins; C M Anderson; B Lia
Publication Detail:
Type:  Journal Article; Research Support, U.S. Gov't, P.H.S.    
Journal Detail:
Title:  Vision research     Volume:  39     ISSN:  0042-6989     ISO Abbreviation:  Vision Res.     Publication Date:  1999 Sep 
Date Detail:
Created Date:  2000-01-24     Completed Date:  2000-01-24     Revised Date:  2007-11-14    
Medline Journal Info:
Nlm Unique ID:  0417402     Medline TA:  Vision Res     Country:  ENGLAND    
Other Details:
Languages:  eng     Pagination:  3223-39     Citation Subset:  IM    
Affiliation:
Department of Psychology, University of California, San Diego, La Jolla 92093, USA. kdobkins@ucsd.edu
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Adult
Color Perception / physiology*
Contrast Sensitivity / physiology*
Female
Humans
Infant
Male
Photic Stimulation
Retina / growth & development
Visual Pathways / physiology*
Grant Support
ID/Acronym/Agency:
EY12153/EY/NEI NIH HHS

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Mechanisms of perceptual learning.
Next Document:  Flicker and the efficiency of cues for capturing attention.