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Further evidence against a momentum explanation for IOR.

Harris JW, Cowper-Smith CD, Klein RM, Westwood DA - PLoS ONE (2015)

Bottom Line: This observation can be explained as a result of inhibition at the attended location (IOR), or as facilitation at the location opposite the cue (opposite facilitation effect or OFE).Past research has demonstrated that IOR is observed reliably, whereas OFE is observed only occasionally.The present series of four experiments allows us to determine whether or not OFE can be explained by eye movements as suggested by previous authors.

View Article: PubMed Central - PubMed

Affiliation: Division of Kinesiology, School of Health and Human Performance, Faculty of Health Professions, Dalhousie University, Halifax, NS, Canada.

ABSTRACT
Reaction times to targets presented in the same location as a preceding cue are greater than those to targets presented opposite the cued location. This observation can be explained as a result of inhibition at the attended location (IOR), or as facilitation at the location opposite the cue (opposite facilitation effect or OFE). Past research has demonstrated that IOR is observed reliably, whereas OFE is observed only occasionally. The present series of four experiments allows us to determine whether or not OFE can be explained by eye movements as suggested by previous authors. Participants' eye movements were monitored as they were presented with an array of four placeholders aligned with the four cardinal axes. Exogenous cues and targets were presented successively. Participants (N=37) completed either: i.) cue-manual and cue-saccade experiments, ignoring the cue and then responding with a keypress or saccade, respectively, or ii.) manual-manual and saccade-saccade experiments, responding to both the cue and the target with a keypress or saccade respectively. Results demonstrated a reliable IOR effect in each of the four experiments (reaction time greater for same versus adjacent and opposite cue-target trials). None of the four experiments demonstrated evidence of an OFE (reaction times were not significantly lower for opposite versus adjacent cue-target trials). These results are inconsistent with a momentum-based account of cue-target task performance, and furthermore suggest that the OFE cannot be attributed to occasional eye movements to the cue and/or target in previous studies.

No MeSH data available.


Related in: MedlinePlus

Sequence of events in each experiment (a). See text for explanation. Conditions for Experiments 1–4 (b). See text for explanation.
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pone.0123666.g002: Sequence of events in each experiment (a). See text for explanation. Conditions for Experiments 1–4 (b). See text for explanation.

Mentions: Each trial began with the presentation of a small circle at the centre of the screen to perform a drift correction procedure. Participants were required to fixate this central circle and press spacebar to initiate the trial. If the participant’s gaze was not located within 10.68 degrees of visual angle of the centre circle, a tone was presented, indicating that the participant should realign their gaze with the centre circle and press spacebar. This process continued until an acceptable calibration had been achieved. Participants were then presented with the four-placeholder array for 500 ms. Participants were instructed to maintain gaze at centre. Next, one of the four peripheral placeholders was bolded (to double its original line width) for 300 ms (Cue) after which it was restored to its usual line width for 200 ms (thus bringing the total duration of the “Cue” phase to 500 ms, as indicated in Fig 2A). In cue-manual (E3) and cue-saccade (E1) experiments, participants were required to ignore the cue and maintain gaze at centre. In manual-manual (E4) and saccade-saccade (E2) experiments, participants were required to respond to the cue by making manual detection (i.e., press a single key to acknowledge the onset of the stimulus) or saccadic responses (i.e., look at the cue), respectively.


Further evidence against a momentum explanation for IOR.

Harris JW, Cowper-Smith CD, Klein RM, Westwood DA - PLoS ONE (2015)

Sequence of events in each experiment (a). See text for explanation. Conditions for Experiments 1–4 (b). See text for explanation.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4400106&req=5

pone.0123666.g002: Sequence of events in each experiment (a). See text for explanation. Conditions for Experiments 1–4 (b). See text for explanation.
Mentions: Each trial began with the presentation of a small circle at the centre of the screen to perform a drift correction procedure. Participants were required to fixate this central circle and press spacebar to initiate the trial. If the participant’s gaze was not located within 10.68 degrees of visual angle of the centre circle, a tone was presented, indicating that the participant should realign their gaze with the centre circle and press spacebar. This process continued until an acceptable calibration had been achieved. Participants were then presented with the four-placeholder array for 500 ms. Participants were instructed to maintain gaze at centre. Next, one of the four peripheral placeholders was bolded (to double its original line width) for 300 ms (Cue) after which it was restored to its usual line width for 200 ms (thus bringing the total duration of the “Cue” phase to 500 ms, as indicated in Fig 2A). In cue-manual (E3) and cue-saccade (E1) experiments, participants were required to ignore the cue and maintain gaze at centre. In manual-manual (E4) and saccade-saccade (E2) experiments, participants were required to respond to the cue by making manual detection (i.e., press a single key to acknowledge the onset of the stimulus) or saccadic responses (i.e., look at the cue), respectively.

Bottom Line: This observation can be explained as a result of inhibition at the attended location (IOR), or as facilitation at the location opposite the cue (opposite facilitation effect or OFE).Past research has demonstrated that IOR is observed reliably, whereas OFE is observed only occasionally.The present series of four experiments allows us to determine whether or not OFE can be explained by eye movements as suggested by previous authors.

View Article: PubMed Central - PubMed

Affiliation: Division of Kinesiology, School of Health and Human Performance, Faculty of Health Professions, Dalhousie University, Halifax, NS, Canada.

ABSTRACT
Reaction times to targets presented in the same location as a preceding cue are greater than those to targets presented opposite the cued location. This observation can be explained as a result of inhibition at the attended location (IOR), or as facilitation at the location opposite the cue (opposite facilitation effect or OFE). Past research has demonstrated that IOR is observed reliably, whereas OFE is observed only occasionally. The present series of four experiments allows us to determine whether or not OFE can be explained by eye movements as suggested by previous authors. Participants' eye movements were monitored as they were presented with an array of four placeholders aligned with the four cardinal axes. Exogenous cues and targets were presented successively. Participants (N=37) completed either: i.) cue-manual and cue-saccade experiments, ignoring the cue and then responding with a keypress or saccade, respectively, or ii.) manual-manual and saccade-saccade experiments, responding to both the cue and the target with a keypress or saccade respectively. Results demonstrated a reliable IOR effect in each of the four experiments (reaction time greater for same versus adjacent and opposite cue-target trials). None of the four experiments demonstrated evidence of an OFE (reaction times were not significantly lower for opposite versus adjacent cue-target trials). These results are inconsistent with a momentum-based account of cue-target task performance, and furthermore suggest that the OFE cannot be attributed to occasional eye movements to the cue and/or target in previous studies.

No MeSH data available.


Related in: MedlinePlus