Reduced visual cortical plasticity in autism spectrum disorder.

Area of Science:

• Neuroscience
• Developmental Neuroscience
• Autism Research

Background:

• Altered NMDA-receptor function is increasingly implicated in autism spectrum disorder (ASD).
• Investigating NMDA-dependent cortical plasticity offers insights into ASD pathophysiology.
• Visual cortex plasticity is crucial for sensory processing and can be modulated by specific stimulation protocols.

Purpose of the Study:

• To investigate potential alterations in NMDA-dependent cortical plasticity in the visual cortex of individuals with ASD.
• To compare the effects of high-frequency visual stimulation (HFS) on visual evoked potentials (VEPs) between individuals with ASD and neurotypical (NT) controls.

Main Methods:

• Assessed persistent changes in VEPs following HFS in 16 individuals with ASD and 15 NT controls.
• VEPs were elicited using a checkerboard pattern before and after HFS (8.87 Hz, 2 min).
• Difference waves were analyzed to quantify plasticity changes, with group differences assessed.

Main Results:

• High-frequency stimulation (HFS) induced reduced short-term potentiation of VEPs in individuals with ASD compared to NT controls.
• While ASD participants showed immediate VEP potentiation, it was not sustained as in NT participants.
• Increased visual stimulus sensitivity in ASD correlated with greater short-term potentiation, with no group differences in neural entrainment or task performance.

Conclusions:

• Visual cortical plasticity appears atypical in individuals with autism spectrum disorder.
• These findings align with evidence suggesting altered NMDA receptor function in ASD.
• The study highlights potential differences in sensory processing and plasticity mechanisms in ASD.