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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

Experimental task and results.A) Subjects viewed RSVP streams of letters. Target 1 (T1) was coloured red, Target 2 (T2) green and the distractors white. T2 could appear at Lag4 or 10. In the prime present trials, a distractor (priming distractor, PD) with the same identity as T2 appeared at Lag2. All stimuli had different identities in the prime absent trials. Subjects were required to report T1 and T2 at the end of each RSVP stream. B) Effects of the priming distractor and Lag on T2/T1 accuracy. Errors bars represent standard error of the mean. C) Scatter plot of relationship between the AB (prime absent) and Lag4 distractor priming magnitude (T2/T1 % correct at Lag 4 in prime present trials – T2/T1 % correct at Lag 4 in prime absent trials). D) Scatter plot of relationship between Lag4 distractor priming magnitude and T1 accuracy (prime absent trials).
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pone-0003330-g001: Experimental task and results.A) Subjects viewed RSVP streams of letters. Target 1 (T1) was coloured red, Target 2 (T2) green and the distractors white. T2 could appear at Lag4 or 10. In the prime present trials, a distractor (priming distractor, PD) with the same identity as T2 appeared at Lag2. All stimuli had different identities in the prime absent trials. Subjects were required to report T1 and T2 at the end of each RSVP stream. B) Effects of the priming distractor and Lag on T2/T1 accuracy. Errors bars represent standard error of the mean. C) Scatter plot of relationship between the AB (prime absent) and Lag4 distractor priming magnitude (T2/T1 % correct at Lag 4 in prime present trials – T2/T1 % correct at Lag 4 in prime absent trials). D) Scatter plot of relationship between Lag4 distractor priming magnitude and T1 accuracy (prime absent trials).

Mentions: RSVP streams contained uppercase letters drawn from the alphabet excluding I, L, O, Q, U and V. T1 was red, T2 green, distractors white and the background grey. T1 appeared at serial position 5 and T2 at Lag4 or Lag10. A fixation square presented for 493 ms preceded all trials, while each stimulus appeared for 93.3 ms, with 17 of these stimuli presented in each trial. For the “prime absent” trials, all stimuli differed, while in the “prime present” trials the second distractor after T1 had the same identity as T2 (priming distractor; Figure 1A). This distractor appeared at the time of maximal blink (Lag2[5]) so that it was unlikely to be consciously perceived. Subjects typed the target identities when visually prompted at the conclusion of each stream. They performed 20 practice trials and 200 test trials, with the presentations of the four trial types randomly intermixed. The experiment was programmed in MATLAB using the Psychophysics toolbox[15], [16].


Distractor inhibition predicts individual differences in the attentional blink.

Dux PE, Marois R - PLoS ONE (2008)

Experimental task and results.A) Subjects viewed RSVP streams of letters. Target 1 (T1) was coloured red, Target 2 (T2) green and the distractors white. T2 could appear at Lag4 or 10. In the prime present trials, a distractor (priming distractor, PD) with the same identity as T2 appeared at Lag2. All stimuli had different identities in the prime absent trials. Subjects were required to report T1 and T2 at the end of each RSVP stream. B) Effects of the priming distractor and Lag on T2/T1 accuracy. Errors bars represent standard error of the mean. C) Scatter plot of relationship between the AB (prime absent) and Lag4 distractor priming magnitude (T2/T1 % correct at Lag 4 in prime present trials – T2/T1 % correct at Lag 4 in prime absent trials). D) Scatter plot of relationship between Lag4 distractor priming magnitude and T1 accuracy (prime absent trials).
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getmorefigures.php?uid=PMC2553194&req=5

pone-0003330-g001: Experimental task and results.A) Subjects viewed RSVP streams of letters. Target 1 (T1) was coloured red, Target 2 (T2) green and the distractors white. T2 could appear at Lag4 or 10. In the prime present trials, a distractor (priming distractor, PD) with the same identity as T2 appeared at Lag2. All stimuli had different identities in the prime absent trials. Subjects were required to report T1 and T2 at the end of each RSVP stream. B) Effects of the priming distractor and Lag on T2/T1 accuracy. Errors bars represent standard error of the mean. C) Scatter plot of relationship between the AB (prime absent) and Lag4 distractor priming magnitude (T2/T1 % correct at Lag 4 in prime present trials – T2/T1 % correct at Lag 4 in prime absent trials). D) Scatter plot of relationship between Lag4 distractor priming magnitude and T1 accuracy (prime absent trials).
Mentions: RSVP streams contained uppercase letters drawn from the alphabet excluding I, L, O, Q, U and V. T1 was red, T2 green, distractors white and the background grey. T1 appeared at serial position 5 and T2 at Lag4 or Lag10. A fixation square presented for 493 ms preceded all trials, while each stimulus appeared for 93.3 ms, with 17 of these stimuli presented in each trial. For the “prime absent” trials, all stimuli differed, while in the “prime present” trials the second distractor after T1 had the same identity as T2 (priming distractor; Figure 1A). This distractor appeared at the time of maximal blink (Lag2[5]) so that it was unlikely to be consciously perceived. Subjects typed the target identities when visually prompted at the conclusion of each stream. They performed 20 practice trials and 200 test trials, with the presentations of the four trial types randomly intermixed. The experiment was programmed in MATLAB using the Psychophysics toolbox[15], [16].

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