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Distractor inhibition predicts individual differences in the attentional blink.

Dux PE, Marois R - PLoS ONE (2008)

Bottom Line: Individual subjects' magnitude of T2 priming from this distractor was found to be negatively correlated with their T1 accuracy and positively related to their AB magnitude.In particular, subjects with attenuated ABs showed negative priming (i.e., worse T2 performance when the priming distractor appeared in the RSVP stream compared to when it was absent), whereas those with large ABs displayed positive priming (i.e., better T2 performance when the priming distractor appeared in the RSVP stream compared to when it was absent).Thus, a subject's ability to suppress distractors, as assessed by T2 priming magnitude, predicted both their T1 performance and AB magnitude.

View Article: PubMed Central - PubMed

Affiliation: Department of Psychology, Vanderbilt Vision Research Center, Center for Integrative and Cognitive Neurosciences, Vanderbilt University, Nashville, TN, USA. paul.dux@vanderbilt.edu

ABSTRACT

Background: The attentional blink (AB) refers to humans' impaired ability to detect the second of two targets (T2) in a rapid serial visual presentation (RSVP) stream of distractors if it appears within 200-600 ms of the first target (T1). Here we examined whether humans' ability to inhibit distractors in the RSVP stream is a key determinant of individual differences in T1 performance and AB magnitude.

Methodology/principal findings: We presented subjects with RSVP streams (93.3 ms/item) of letters containing white distractors, a red T1 and a green T2. Subjects' ability to suppress distractors was assessed by determining the extent to which their second target performance was primed by a preceding distractor that shared the same identity as T2. Individual subjects' magnitude of T2 priming from this distractor was found to be negatively correlated with their T1 accuracy and positively related to their AB magnitude. In particular, subjects with attenuated ABs showed negative priming (i.e., worse T2 performance when the priming distractor appeared in the RSVP stream compared to when it was absent), whereas those with large ABs displayed positive priming (i.e., better T2 performance when the priming distractor appeared in the RSVP stream compared to when it was absent). Thus, a subject's ability to suppress distractors, as assessed by T2 priming magnitude, predicted both their T1 performance and AB magnitude.

Conclusions/significance: These results confirm that distractor suppression plays a key role in RSVP target selection and support the hypothesis that the AB results, at least in part, from a failure of distractor inhibition.

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Related in: MedlinePlus

Priming magnitude in subjects with large and small ABs.Lag4 and Lag10 priming magnitude (T2/T1 % correct at Lag4/10 in prime present trials – T2/T1 % correct at Lag4/10 in prime absent trials) in the low (15 subs with the lowest AB magnitude: Low AB Mag) and high (15 subs with the highest AB magnitude: High AB Mag) AB magnitude groups. Errors bars represent standard error of the mean.
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pone-0003330-g002: Priming magnitude in subjects with large and small ABs.Lag4 and Lag10 priming magnitude (T2/T1 % correct at Lag4/10 in prime present trials – T2/T1 % correct at Lag4/10 in prime absent trials) in the low (15 subs with the lowest AB magnitude: Low AB Mag) and high (15 subs with the highest AB magnitude: High AB Mag) AB magnitude groups. Errors bars represent standard error of the mean.

Mentions: In a final analysis, we sought to confirm that subjects who exhibited reduced ABs did so because of distractor suppression rather than simply a failure to excite the distractor representations (i. e., they did not process the distractor stimuli). As previously discussed, if subjects actively inhibit distractors than the presence of the prime should impair T2 performance as this target's representation will be more difficult to reactivate once suppressed. Conversely, if subjects do not process distractors then there should be little to no effect of the prime on T2 performance, as the priming distractor will not activate this target's representation. To test this, we sorted our subjects based on the size of their AB in the prime absent condition, and compared the priming magnitude in those subjects with the smallest ABs (AB magnitude < = 30%, mean AB magnitude = 19%, n = 15) to those with the largest ABs (AB magnitude >46%, mean AB magnitude = 54.1%, n = 15). These two groups significantly differed in terms of AB magnitude, t(28) = 14.1, p<.001. Figure 2 shows that for subjects with large ABs the priming distractor led to superior T2/T1 performance at Lag4, t(14) = 5.1, p<.001, but not at Lag10 (p = .59). By contrast, for the subjects with reduced ABs the priming distractor significantly impaired T2/T1 accuracy at Lag4, t(14) = −2.1, p = .05, but not at Lag10 (p = .96). In addition, there was no effect of the prime at either Lag4 or Lag10 (ps>.25) in the remaining subjects with intermediate AB magnitude (mean AB magnitude = 38.6%, n = 18). Thus, it appears that subjects with reduced ABs, do indeed inhibit distractors. This is further support for the hypothesis that a failure of distractor inhibition contributes to the AB.


Distractor inhibition predicts individual differences in the attentional blink.

Dux PE, Marois R - PLoS ONE (2008)

Priming magnitude in subjects with large and small ABs.Lag4 and Lag10 priming magnitude (T2/T1 % correct at Lag4/10 in prime present trials – T2/T1 % correct at Lag4/10 in prime absent trials) in the low (15 subs with the lowest AB magnitude: Low AB Mag) and high (15 subs with the highest AB magnitude: High AB Mag) AB magnitude groups. Errors bars represent standard error of the mean.
© Copyright Policy
Related In: Results  -  Collection

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getmorefigures.php?uid=PMC2553194&req=5

pone-0003330-g002: Priming magnitude in subjects with large and small ABs.Lag4 and Lag10 priming magnitude (T2/T1 % correct at Lag4/10 in prime present trials – T2/T1 % correct at Lag4/10 in prime absent trials) in the low (15 subs with the lowest AB magnitude: Low AB Mag) and high (15 subs with the highest AB magnitude: High AB Mag) AB magnitude groups. Errors bars represent standard error of the mean.
Mentions: In a final analysis, we sought to confirm that subjects who exhibited reduced ABs did so because of distractor suppression rather than simply a failure to excite the distractor representations (i. e., they did not process the distractor stimuli). As previously discussed, if subjects actively inhibit distractors than the presence of the prime should impair T2 performance as this target's representation will be more difficult to reactivate once suppressed. Conversely, if subjects do not process distractors then there should be little to no effect of the prime on T2 performance, as the priming distractor will not activate this target's representation. To test this, we sorted our subjects based on the size of their AB in the prime absent condition, and compared the priming magnitude in those subjects with the smallest ABs (AB magnitude < = 30%, mean AB magnitude = 19%, n = 15) to those with the largest ABs (AB magnitude >46%, mean AB magnitude = 54.1%, n = 15). These two groups significantly differed in terms of AB magnitude, t(28) = 14.1, p<.001. Figure 2 shows that for subjects with large ABs the priming distractor led to superior T2/T1 performance at Lag4, t(14) = 5.1, p<.001, but not at Lag10 (p = .59). By contrast, for the subjects with reduced ABs the priming distractor significantly impaired T2/T1 accuracy at Lag4, t(14) = −2.1, p = .05, but not at Lag10 (p = .96). In addition, there was no effect of the prime at either Lag4 or Lag10 (ps>.25) in the remaining subjects with intermediate AB magnitude (mean AB magnitude = 38.6%, n = 18). Thus, it appears that subjects with reduced ABs, do indeed inhibit distractors. This is further support for the hypothesis that a failure of distractor inhibition contributes to the AB.

Bottom Line: Individual subjects' magnitude of T2 priming from this distractor was found to be negatively correlated with their T1 accuracy and positively related to their AB magnitude.In particular, subjects with attenuated ABs showed negative priming (i.e., worse T2 performance when the priming distractor appeared in the RSVP stream compared to when it was absent), whereas those with large ABs displayed positive priming (i.e., better T2 performance when the priming distractor appeared in the RSVP stream compared to when it was absent).Thus, a subject's ability to suppress distractors, as assessed by T2 priming magnitude, predicted both their T1 performance and AB magnitude.

View Article: PubMed Central - PubMed

Affiliation: Department of Psychology, Vanderbilt Vision Research Center, Center for Integrative and Cognitive Neurosciences, Vanderbilt University, Nashville, TN, USA. paul.dux@vanderbilt.edu

ABSTRACT

Background: The attentional blink (AB) refers to humans' impaired ability to detect the second of two targets (T2) in a rapid serial visual presentation (RSVP) stream of distractors if it appears within 200-600 ms of the first target (T1). Here we examined whether humans' ability to inhibit distractors in the RSVP stream is a key determinant of individual differences in T1 performance and AB magnitude.

Methodology/principal findings: We presented subjects with RSVP streams (93.3 ms/item) of letters containing white distractors, a red T1 and a green T2. Subjects' ability to suppress distractors was assessed by determining the extent to which their second target performance was primed by a preceding distractor that shared the same identity as T2. Individual subjects' magnitude of T2 priming from this distractor was found to be negatively correlated with their T1 accuracy and positively related to their AB magnitude. In particular, subjects with attenuated ABs showed negative priming (i.e., worse T2 performance when the priming distractor appeared in the RSVP stream compared to when it was absent), whereas those with large ABs displayed positive priming (i.e., better T2 performance when the priming distractor appeared in the RSVP stream compared to when it was absent). Thus, a subject's ability to suppress distractors, as assessed by T2 priming magnitude, predicted both their T1 performance and AB magnitude.

Conclusions/significance: These results confirm that distractor suppression plays a key role in RSVP target selection and support the hypothesis that the AB results, at least in part, from a failure of distractor inhibition.

Show MeSH
Related in: MedlinePlus