Motion- and orientation-specific cortical responses in infancy.
During the first 3 months, infants develop visual evoked potential (VEP) responses that are signatures of cortical orientation-selectivity and directional motion selectivity. Orientation-specific cortical responses develop in early infancy. This study compared these responses directly in the same in...
| Main Authors: | , , , |
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| Format: | Journal article |
| Language: | English |
| Published: |
2005
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| _version_ | 1826282762535960576 |
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| author | Braddick, O Birtles, D Wattam-Bell, J Atkinson, J |
| author_facet | Braddick, O Birtles, D Wattam-Bell, J Atkinson, J |
| author_sort | Braddick, O |
| collection | OXFORD |
| description | During the first 3 months, infants develop visual evoked potential (VEP) responses that are signatures of cortical orientation-selectivity and directional motion selectivity. Orientation-specific cortical responses develop in early infancy. This study compared these responses directly in the same infants, to investigate whether the later appearance of direction selectivity was intrinsic, or a function of the spatio-temporal characteristics of the stimuli used. Steady-state orientation-reversal (OR-) VEPs and direction-reversal (DR-) VEPs were recorded in infants aged 4-18 weeks. DR-VEPs were elicited with random pixel patterns and with gratings spatially similar to those used for OR-VEPs, at velocities of 5.5 and 11 deg/s, and reversal rates of 2 and 4 reversals/s. Infants throughout the age range showed significant responses to orientation-reversal. Direction-reversal responses appeared in less than 25% of infants under 7 weeks of age, rising to 80% or more at 11-13 weeks, whether tested with dots or gratings and for both speeds and reversal rates. However, 2 reversals/s elicits the DR-VEP on average about 2 weeks earlier than 4 reversal/s stimulation. We conclude that human cortical direction selectivity develops separately from orientation-selectivity and emerges at a later age, even with tests that are designed to optimise the former. |
| first_indexed | 2024-03-07T00:48:45Z |
| format | Journal article |
| id | oxford-uuid:859e8b4d-5d68-4259-a3e8-139aa48506a1 |
| institution | University of Oxford |
| language | English |
| last_indexed | 2024-03-07T00:48:45Z |
| publishDate | 2005 |
| record_format | dspace |
| spelling | oxford-uuid:859e8b4d-5d68-4259-a3e8-139aa48506a12022-03-26T21:58:44ZMotion- and orientation-specific cortical responses in infancy.Journal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:859e8b4d-5d68-4259-a3e8-139aa48506a1EnglishSymplectic Elements at Oxford2005Braddick, OBirtles, DWattam-Bell, JAtkinson, JDuring the first 3 months, infants develop visual evoked potential (VEP) responses that are signatures of cortical orientation-selectivity and directional motion selectivity. Orientation-specific cortical responses develop in early infancy. This study compared these responses directly in the same infants, to investigate whether the later appearance of direction selectivity was intrinsic, or a function of the spatio-temporal characteristics of the stimuli used. Steady-state orientation-reversal (OR-) VEPs and direction-reversal (DR-) VEPs were recorded in infants aged 4-18 weeks. DR-VEPs were elicited with random pixel patterns and with gratings spatially similar to those used for OR-VEPs, at velocities of 5.5 and 11 deg/s, and reversal rates of 2 and 4 reversals/s. Infants throughout the age range showed significant responses to orientation-reversal. Direction-reversal responses appeared in less than 25% of infants under 7 weeks of age, rising to 80% or more at 11-13 weeks, whether tested with dots or gratings and for both speeds and reversal rates. However, 2 reversals/s elicits the DR-VEP on average about 2 weeks earlier than 4 reversal/s stimulation. We conclude that human cortical direction selectivity develops separately from orientation-selectivity and emerges at a later age, even with tests that are designed to optimise the former. |
| spellingShingle | Braddick, O Birtles, D Wattam-Bell, J Atkinson, J Motion- and orientation-specific cortical responses in infancy. |
| title | Motion- and orientation-specific cortical responses in infancy. |
| title_full | Motion- and orientation-specific cortical responses in infancy. |
| title_fullStr | Motion- and orientation-specific cortical responses in infancy. |
| title_full_unstemmed | Motion- and orientation-specific cortical responses in infancy. |
| title_short | Motion- and orientation-specific cortical responses in infancy. |
| title_sort | motion and orientation specific cortical responses in infancy |
| work_keys_str_mv | AT braddicko motionandorientationspecificcorticalresponsesininfancy AT birtlesd motionandorientationspecificcorticalresponsesininfancy AT wattambellj motionandorientationspecificcorticalresponsesininfancy AT atkinsonj motionandorientationspecificcorticalresponsesininfancy |