Orientation selectivity in rat primary visual cortex emerges earlier with low-contrast and high-luminance stimuli

Research output: Contribution to journalArticleResearchpeer-review

5 Citations (Scopus)

Abstract

In natural vision, rapid and sustained variations in luminance and contrast change the reliability of information available about a visual scene, and markedly affect both neuronal and behavioural responses. The hallmark property of neurons in primary visual cortex (V1), orientation selectivity, is unaffected by changes in stimulus contrast, but it remains unclear how sustained differences in mean luminance and contrast affect the time-course of orientation selectivity, and the amount of information that neurons carry about orientation. We used reverse correlation with characterize the temporal dynamics of orientation selectivity in rat V1 neurons under four luminance-contrast conditions. We show that orientation selectivity and mutual information between neuronal responses and stimulus orientation are invariant to contrast or mean luminance. Critically, the time-course of the emergence of orientation selectivity was affected by both factors; response latencies were longer for low- than high-luminance gratings, and surprisingly, response latencies were also longer for high- than low-contrast gratings. Modelling suggests that luminance-modulated changes in feedforward gain, in combination with hyperpolarization caused by high contrasts can account for our physiological data. The hyperpolarization at high contrasts may increase signal-to-noise ratios, whereas a more depolarized membrane may lead to greater sensitivity to weak stimuli.

Original languageEnglish
Pages (from-to)2759-2773
Number of pages15
JournalEuropean Journal of Neuroscience
Volume44
Issue number10
DOIs
Publication statusPublished - 1 Nov 2016

Keywords

  • adaptation
  • computational model
  • electrophysiology
  • rodent vision
  • V1

Cite this

@article{2ad78983398e4b1680fc2cea5876d656,
title = "Orientation selectivity in rat primary visual cortex emerges earlier with low-contrast and high-luminance stimuli",
abstract = "In natural vision, rapid and sustained variations in luminance and contrast change the reliability of information available about a visual scene, and markedly affect both neuronal and behavioural responses. The hallmark property of neurons in primary visual cortex (V1), orientation selectivity, is unaffected by changes in stimulus contrast, but it remains unclear how sustained differences in mean luminance and contrast affect the time-course of orientation selectivity, and the amount of information that neurons carry about orientation. We used reverse correlation with characterize the temporal dynamics of orientation selectivity in rat V1 neurons under four luminance-contrast conditions. We show that orientation selectivity and mutual information between neuronal responses and stimulus orientation are invariant to contrast or mean luminance. Critically, the time-course of the emergence of orientation selectivity was affected by both factors; response latencies were longer for low- than high-luminance gratings, and surprisingly, response latencies were also longer for high- than low-contrast gratings. Modelling suggests that luminance-modulated changes in feedforward gain, in combination with hyperpolarization caused by high contrasts can account for our physiological data. The hyperpolarization at high contrasts may increase signal-to-noise ratios, whereas a more depolarized membrane may lead to greater sensitivity to weak stimuli.",
keywords = "adaptation, computational model, electrophysiology, rodent vision, V1",
author = "Masoud Ghodrati and Alwis, {Dasuni S.} and Price, {Nicholas S. C.}",
year = "2016",
month = "11",
day = "1",
doi = "10.1111/ejn.13379",
language = "English",
volume = "44",
pages = "2759--2773",
journal = "European Journal of Neuroscience",
issn = "0953-816X",
publisher = "Wiley-Blackwell",
number = "10",

}

Orientation selectivity in rat primary visual cortex emerges earlier with low-contrast and high-luminance stimuli. / Ghodrati, Masoud; Alwis, Dasuni S.; Price, Nicholas S. C.

In: European Journal of Neuroscience, Vol. 44, No. 10, 01.11.2016, p. 2759-2773.

Research output: Contribution to journalArticleResearchpeer-review

TY - JOUR

T1 - Orientation selectivity in rat primary visual cortex emerges earlier with low-contrast and high-luminance stimuli

AU - Ghodrati, Masoud

AU - Alwis, Dasuni S.

AU - Price, Nicholas S. C.

PY - 2016/11/1

Y1 - 2016/11/1

N2 - In natural vision, rapid and sustained variations in luminance and contrast change the reliability of information available about a visual scene, and markedly affect both neuronal and behavioural responses. The hallmark property of neurons in primary visual cortex (V1), orientation selectivity, is unaffected by changes in stimulus contrast, but it remains unclear how sustained differences in mean luminance and contrast affect the time-course of orientation selectivity, and the amount of information that neurons carry about orientation. We used reverse correlation with characterize the temporal dynamics of orientation selectivity in rat V1 neurons under four luminance-contrast conditions. We show that orientation selectivity and mutual information between neuronal responses and stimulus orientation are invariant to contrast or mean luminance. Critically, the time-course of the emergence of orientation selectivity was affected by both factors; response latencies were longer for low- than high-luminance gratings, and surprisingly, response latencies were also longer for high- than low-contrast gratings. Modelling suggests that luminance-modulated changes in feedforward gain, in combination with hyperpolarization caused by high contrasts can account for our physiological data. The hyperpolarization at high contrasts may increase signal-to-noise ratios, whereas a more depolarized membrane may lead to greater sensitivity to weak stimuli.

AB - In natural vision, rapid and sustained variations in luminance and contrast change the reliability of information available about a visual scene, and markedly affect both neuronal and behavioural responses. The hallmark property of neurons in primary visual cortex (V1), orientation selectivity, is unaffected by changes in stimulus contrast, but it remains unclear how sustained differences in mean luminance and contrast affect the time-course of orientation selectivity, and the amount of information that neurons carry about orientation. We used reverse correlation with characterize the temporal dynamics of orientation selectivity in rat V1 neurons under four luminance-contrast conditions. We show that orientation selectivity and mutual information between neuronal responses and stimulus orientation are invariant to contrast or mean luminance. Critically, the time-course of the emergence of orientation selectivity was affected by both factors; response latencies were longer for low- than high-luminance gratings, and surprisingly, response latencies were also longer for high- than low-contrast gratings. Modelling suggests that luminance-modulated changes in feedforward gain, in combination with hyperpolarization caused by high contrasts can account for our physiological data. The hyperpolarization at high contrasts may increase signal-to-noise ratios, whereas a more depolarized membrane may lead to greater sensitivity to weak stimuli.

KW - adaptation

KW - computational model

KW - electrophysiology

KW - rodent vision

KW - V1

UR - http://www.scopus.com/inward/record.url?scp=84987763103&partnerID=8YFLogxK

U2 - 10.1111/ejn.13379

DO - 10.1111/ejn.13379

M3 - Article

VL - 44

SP - 2759

EP - 2773

JO - European Journal of Neuroscience

JF - European Journal of Neuroscience

SN - 0953-816X

IS - 10

ER -