Poster Session: Characterising colour processing in anomalous trichromacy with steady-state visually evoked...

Area of Science:

• Neuroscience
• Vision Science
• Human Physiology

Background:

• Color vision relies on short (S), medium (M), and long (L) cone photoreceptors.
• Post-receptoral processing involves cone-opponent mechanisms (L/(L+M) and S/(L+M)).
• Anomalous trichromacy features reduced L and M cone spectral sensitivity separation, impacting L/(M+L) color discrimination.

Purpose of the Study:

• To investigate the site of post-receptoral color signal compensation in anomalous trichromacy.
• To differentiate between retinal and cortical compensation mechanisms.
• To present a novel electroencephalography-based method for studying these processes.

Main Methods:

• Utilized steady-state visually evoked potentials (SSVEPs) via electroencephalography.
• Measured SSVEP signals in response to flickering stimuli targeting S/(L+M) and L/(L+M) mechanisms.
• Assessed signals at both retinal and cortical levels to identify compensation sites.

Main Results:

• The study did not exclude retinal compensation, contrasting with some prior fMRI findings.
• Investigated whether reduced L/(L+M) SSVEP signals in anomalous trichromats are rectified at the cortical level.
• Established a novel SSVEP approach for characterizing color vision compensation.

Conclusions:

• Post-receptoral compensation in anomalous trichromacy is a complex process potentially involving multiple sites.
• The developed SSVEP method offers a new avenue for investigating the neural basis of color vision deficiencies.
• Further research is needed to fully elucidate the interplay between retinal and cortical mechanisms in color processing.