The Time Course of Inhibition of Return: Evidence from Steady-State Visual Evoked Potentials

Abstract

Inhibition of return (IOR) refers to slower responses to targets at a previously cued location than that at an uncued location. The time course of IOR has long been a topic of interest in the field. Investigations into the time course of IOR are typically performed by examining the magnitude of IOR under various cue-target onset asynchrony (CTOA) conditions. Therefore, the results are vulnerable to influence of factors that could affect the target processes (e.g., the frequency of the target type). In the present study, steady-state visual evoked potentials (SSVEPs) were implemented to directly take a continuous measurement of the degree to which cued location is processed, eliminating the influence mentioned above. The results indicate that, relative to the baseline interval (−400 to 0 ms), the presence of peripheral cues generated a typical two-stage effect on the SSVEP amplitude evoked by a 20 Hz flicker. Specifically, after the onset of the peripheral cues, the SSVEP amplitude first showed a significant increase, which subsequently turned into a significant inhibition effect after 200 ms. These results provide a continuous time course diagram of the cueing effect and suggest an effective way for future investigations of controlling the masking effects of target stimuli processing on IOR.

Exploring the temporal dynamics of inhibition of return using steady-state visual evoked potentials

“…However, the IOR-modulated SSVEP effect observed in Li et al (2017) should have been present at both 8 and 20 Hz, not only at 20 Hz, because it has been demonstrated that although SSVEPs are present in the 12-25 Hz and 25-50 Hz ranges (Herrmann, 2001), they are strongest in the alpha range (approximately 8-12 Hz; Herrmann, 2001;Pastor, Artieda, Arbizu, Valencia, & Masdeu, 2003), with maximal responses at about 10 Hz for luminance flickers (Fawcett, Barnes, Hillebrand, & Singh, 2004;Regan, 1966;Srinivasan et al, 2006). The absence of SSVEP modulation at their 8 Hz frequency could potentially be due to the eye movements of participants not being monitored by means of an eye-tracker during the task, which has been found to be a serious confounding factor that could lead to inconsistent IOR results (Chica, Klein, Rafal, & Hopfinger, 2010a;Rafal et al, 1989).…”

“…As an alternative to ERPs, steady-state visual evoked potentials (SSVEPs) are commonly used to investigate visual information processing (Regan, 1968) and allow for attention to be measured continuously (Morgan, Hansen, Hillyard, & Posner, 1996). Compared with ERPs, SSVEPs are easier to quantify (Luck, 2014) and less prone to artifacts (Regan, 1989), making them a valuable tool for measuring attention in paradigms, such as the spatial cueing task (Li et al, 2017).…”

“…More recently, Li et al (2017) investigated IOR using the SSVEP technique in a traditional cueing paradigm with manual responses to targets, in which 8 and 20 Hz flickering backgrounds were displayed at the two possible stimulus locations. Using a CTOA of 1,400 ms, the study observed a transient enhancement in mean SSVEP amplitude (cued = 0.15 μV; uncued = -0.02 μV) ipsilateral to cues displayed on the 20 Hz flickering background in the window of 170-180 ms post-cue, followed by a reduction (cued = −0.12 μV; uncued = -0.02 μV) in the window of 200-800 ms post-cue.…”

“…It is unclear whether this limitation had an impact on the SSVEP responses, but there were inconsistent findings between hemispheres. Specifically, Li et al (2017) found SSVEPs in one hemisphere, but not the other, and subsequent analyses were performed on only the left posterior occipital electrodes (PO3, PO5, and PO7).…”

What Neuroscientific Studies Tell Us about Inhibition of Return

“…A number of studies have demonstrated that these SSVEP signals are modulated by spatial attention (i.e., the signal is enhanced when attended), e.g., [51,52]. As far as we know, only one study [53] has employed this technique to explore the sensory consequences of an uninformative peripheral cue. This study found a biphasic pattern with enhanced signals from the cued location immediately after the appearance of the cue reversing to suppressed signals beginning about 200 ms later.…”