Effect of stimulation shapes on the Steady-State Visual-Evoked response

The strength of Steady-State Visual-Evoked Potentials (SSVEPs) have been observed to greatly depend on the stimulation source and paradigm. Orientation and size specific neurons have been discovered in the occipital cortex, which activate only when excited with specific patterns. Different shapes have different orientation and size aspects that eventually lead to activation of different neuronal groups. In this study, we investigate the potential for a novel shape switching based stimulation paradigm for SSVEP elicitation. Pattern reversal stimuli was found to elicit stronger SSVEP relative to single graphic stimuli. Results indicate that there might exist a subject-dependent connection between the elicited SSVEP and choice of shapes for the stimulation paradigm.