Patching one eye of an adult for a few hours, also termed short-term monocular deprivation (MD), has recently become an interesting research topic on visual plasticity. All the past work has measured the effects of MD using laboratory synthetic stimuli (e.g., gratings). However, it is recognized that complex natural stimuli may engage cortical mechanisms substantially different from simple synthetic stimuli. Therefore, it remains largely unknown how neural activities are changed in response to natural stimuli following the MD.

The Visual Perception and Plasticity Lab led by Prof. BAO Min from the Key Laboratory of Behavioral Science, Institute of Psychology of Chinese Academy of Sciences (CAS) for the first time addressed this issue by using the steady-state visual evoked potential (SSVEP) technique. Before and after 2.5 hours of MD (Figure 1A) was an unfiltered SSVEP test where the stimuli in both eyes were identical unfiltered natural movies (though flickering at different frequencies). During the MD, the test stimuli were same as the adapter, allowing the researchers to track the neural changes over time (Figure 1B).

Figure 1. Experimental design and sequences during the 125 min of MD.

The researchers found that MD boosted the neural gain for the deprived eye as reflected by an increase of the inter-ocular SSVEP amplitude ratio, and the strength for the deprived eye was progressively promoted during the 2.5 hours of deprivation (Figure 2).

Figure 2. The changes of neural ocular dominance during the MD.

These findings demonstrate that the effects of short-term MD can manifest when viewing natural scenes, providing a natural case in support of the homeostatic compensation theory of MD. Furthermore, the technique of natural-scene-based SSVEP could be particularly useful for future work exploring the neural dynamics during adaptation to natural stimuli.

The work was supported by grants from the National Natural Science Foundation of China and the Key Research Program of CAS, and is now published in Neuroscience.

Lyu, L., He, S., Jiang, Y., Engel, S. A., & Bao, M*. (2020). Natural-scene-based Steady-state Visual Evoked Potentials Reveal Effects of Short-term Monocular Deprivation. Neuroscience 435, 10-21. doi: 10.1016/j.neuroscience.2020.03.039.

Paper at Neuroscience

CONTACT:
Ms.LIU Chen

Institute of Psychology, Chinese Academy of Sciences,Beijing 100101, China.

Email: liuc@psych.ac.cn