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NMDA receptor antagonist ketamine impairs feature integration in visual perception.

Meuwese JD, van Loon AM, Scholte HS, Lirk PB, Vulink NC, Hollmann MW, Lamme VA - PLoS ONE (2013)

Bottom Line: Therefore, we tested whether ketamine, a non-competitive NMDA receptor antagonist, reduces feature integration in humans.This effect is not merely due to task difficulty or a difference in sedation levels.We are the first to show a behavioral effect on feature integration by manipulating the NMDA receptor in humans.

View Article: PubMed Central - PubMed

Affiliation: Department of Psychology, University of Amsterdam, Amsterdam, The Netherlands ; Cognitive Science Center Amsterdam, University of Amsterdam, Amsterdam, The Netherlands.

ABSTRACT
Recurrent interactions between neurons in the visual cortex are crucial for the integration of image elements into coherent objects, such as in figure-ground segregation of textured images. Blocking N-methyl-D-aspartate (NMDA) receptors in monkeys can abolish neural signals related to figure-ground segregation and feature integration. However, it is unknown whether this also affects perceptual integration itself. Therefore, we tested whether ketamine, a non-competitive NMDA receptor antagonist, reduces feature integration in humans. We administered a subanesthetic dose of ketamine to healthy subjects who performed a texture discrimination task in a placebo-controlled double blind within-subject design. We found that ketamine significantly impaired performance on the texture discrimination task compared to the placebo condition, while performance on a control fixation task was much less impaired. This effect is not merely due to task difficulty or a difference in sedation levels. We are the first to show a behavioral effect on feature integration by manipulating the NMDA receptor in humans.

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Task performance.Performance on all trials, for the fixation task and texture discrimination task (A). Performance on the texture discrimination task including only correct fixation trials (B) and including only incorrect fixation trials (C). Ketamine administration caused decreased performance on both tasks, but texture discrimination impairments were independent of fixation task performance (impairments were equal for correct and incorrect fixation trials).
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pone-0079326-g002: Task performance.Performance on all trials, for the fixation task and texture discrimination task (A). Performance on the texture discrimination task including only correct fixation trials (B) and including only incorrect fixation trials (C). Ketamine administration caused decreased performance on both tasks, but texture discrimination impairments were independent of fixation task performance (impairments were equal for correct and incorrect fixation trials).

Mentions: As hypothesized, performance on the texture discrimination task was impaired in the ketamine condition compared to the placebo condition (F(1,13) = 14.667, p = .002). However, performance on the fixation task was also affected in the ketamine condition (F(1,13) = 12.068, p = .004) (see Figure 2A).


NMDA receptor antagonist ketamine impairs feature integration in visual perception.

Meuwese JD, van Loon AM, Scholte HS, Lirk PB, Vulink NC, Hollmann MW, Lamme VA - PLoS ONE (2013)

Task performance.Performance on all trials, for the fixation task and texture discrimination task (A). Performance on the texture discrimination task including only correct fixation trials (B) and including only incorrect fixation trials (C). Ketamine administration caused decreased performance on both tasks, but texture discrimination impairments were independent of fixation task performance (impairments were equal for correct and incorrect fixation trials).
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3815103&req=5

pone-0079326-g002: Task performance.Performance on all trials, for the fixation task and texture discrimination task (A). Performance on the texture discrimination task including only correct fixation trials (B) and including only incorrect fixation trials (C). Ketamine administration caused decreased performance on both tasks, but texture discrimination impairments were independent of fixation task performance (impairments were equal for correct and incorrect fixation trials).
Mentions: As hypothesized, performance on the texture discrimination task was impaired in the ketamine condition compared to the placebo condition (F(1,13) = 14.667, p = .002). However, performance on the fixation task was also affected in the ketamine condition (F(1,13) = 12.068, p = .004) (see Figure 2A).

Bottom Line: Therefore, we tested whether ketamine, a non-competitive NMDA receptor antagonist, reduces feature integration in humans.This effect is not merely due to task difficulty or a difference in sedation levels.We are the first to show a behavioral effect on feature integration by manipulating the NMDA receptor in humans.

View Article: PubMed Central - PubMed

Affiliation: Department of Psychology, University of Amsterdam, Amsterdam, The Netherlands ; Cognitive Science Center Amsterdam, University of Amsterdam, Amsterdam, The Netherlands.

ABSTRACT
Recurrent interactions between neurons in the visual cortex are crucial for the integration of image elements into coherent objects, such as in figure-ground segregation of textured images. Blocking N-methyl-D-aspartate (NMDA) receptors in monkeys can abolish neural signals related to figure-ground segregation and feature integration. However, it is unknown whether this also affects perceptual integration itself. Therefore, we tested whether ketamine, a non-competitive NMDA receptor antagonist, reduces feature integration in humans. We administered a subanesthetic dose of ketamine to healthy subjects who performed a texture discrimination task in a placebo-controlled double blind within-subject design. We found that ketamine significantly impaired performance on the texture discrimination task compared to the placebo condition, while performance on a control fixation task was much less impaired. This effect is not merely due to task difficulty or a difference in sedation levels. We are the first to show a behavioral effect on feature integration by manipulating the NMDA receptor in humans.

Show MeSH
Related in: MedlinePlus