Habituation is more Accentuated by Motion-Onset Stimuli than Compared with Pattern Reversal Stimuli - a Pilot Study
Abstract
Introduction: Assessment of habituation (reduced response to repeated stimuli) using visual evoked potential (VEP) amplitudes represents an innovative and so far infrequent application of VEP that, nevertheless, has a potential to be used in research across all disciplines of neuroscience. Objective: The aim of this study was to verify applicability of VEP in assessing habituation and to identify types of visual stimuli (motion versus structural with low or high contrast) that would be the most useful in specific cases.
Methods: A study group of 12 healthy volunteers (9 women, 3 men) aged 22-39 years was tested using three kinds of VEP Pattern Reversal VEP (PR-VEP) with 14% and 85% luminance contrasts, respectively, and Motion-onset VEP (M-VEP). VEPs were recorded in 5 blocks of 60 responses.
Results: The study evaluated amplitude variations of the main components of each type of VEP. Despite high variability in the results and with an exception of the high contrast stimulus, a statistically significant association was found between the time factor and VEP amplitudes (repeated measures ANOVA).
Comparison of the mean amplitude of the first and second block of VEPs with the fifthrevealed statistically smaller amplitudes for the M-VEPs. In the pattern reversal stimulation, the amplitude drop was only statistically significant when comparing the second and the fifth block (Wilcoxon paired test).
Conclusion: M-VEP, as opposed to PR-VEP, seems more suited for the study of habituation.