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Word frequency and the attentional blink: the effects of target difficulty on retrieval and consolidation processes.

Wierda SM, Taatgen NA, van Rijn H, Martens S - PLoS ONE (2013)

Bottom Line: The opposite effect was found for T2.Our results were replicated in a subsequent ERP study.However, it was successfully accounted for by the threaded-cognition model, thus providing an explanation in terms of attentional control.

View Article: PubMed Central - PubMed

Affiliation: Neuroimaging Center, University of Groningen, Groningen, The Netherlands ; Department of Neuroscience, University Medical Center Groningen, Groningen, The Netherlands.

ABSTRACT

Background: When a second target (T2) is presented in close succession of a first target (T1) within a stream of non-targets, people often fail to detect T2-a deficit known as the attentional blink (AB). Two types of theories can be distinguished that have tried to account for this phenomenon. Whereas attentional-control theories suggest that protection of consolidation processes induces the AB, limited-resource theories claim that the AB is caused by a lack of resources. According to the latter type of theories, increasing difficulty of one or both targets should increase the magnitude of the AB. Similarly, attentional-control theories predict that a difficult T1 increases the AB due to prolonged processing. However, the prediction for T2 is not as straightforward. Prolonged processing of T2 could cause conflicts and increase the AB. However, if consolidation of T2 is postponed without loss of identity, the AB might be attenuated.

Methodology/principal findings: Participants performed an AB task that consisted of a stream of distractor non-words and two target words. Difficulty of T1 and T2 was manipulated by varying word-frequency. Overall performance for high-frequency words was better than for low-frequency words. When T1 was highly frequent, the AB was reduced. The opposite effect was found for T2. When T2 was highly frequent, performance during the AB period was relatively worse than for a low-frequency T2. A threaded-cognition model of the AB was presented that simulated the observed pattern of behavior by taking changes in the time-course of retrieval and consolidation processes into account. Our results were replicated in a subsequent ERP study.

Conclusions/significance: The finding that a difficult low-frequency T2 reduces the magnitude of the AB is at odds with limited-resource accounts of the AB. However, it was successfully accounted for by the threaded-cognition model, thus providing an explanation in terms of attentional control.

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Related in: MedlinePlus

Grand averages for the ERPs of high-frequency and low-frequency words at lag 2 (A), 7 (B), and 8 (C).The ERPs are time-locked on target onset. Only correct trials were analyzed.
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pone-0073415-g008: Grand averages for the ERPs of high-frequency and low-frequency words at lag 2 (A), 7 (B), and 8 (C).The ERPs are time-locked on target onset. Only correct trials were analyzed.

Mentions: The EEG data was rereferenced to the mastoid electrodes. In order to remove noise, the data was filtered using a high-pass filter with a cutoff frequency of 1 Hz (24 dB/oct) and a low-pass filter with a cutoff frequency of 40 Hz (24 dB/oct). As we were interested in the activity at the parietal sites, data were then pooled over the parietal electrodes CPz, P1, P2, POz, and Pz. Next, the data were divided in T2-timelocked segments of one second (−200 ms to 800 ms). The 200 ms before onset of T2 served as baseline activity. Segments containing eye-blinks were excluded from analysis. Also, if the difference in voltage between the minimum and maximum data-point in a segments exceeded 100 µVolt, the segment was excluded. The final exclusion criterion was when the difference between two successive data-points exceeded 50 µVolt. In total, three segments were excluded. The grand averages for lag 2, 7, and 8 are shown in Figure 8a, Figure8b, Figure 8c, respectively.


Word frequency and the attentional blink: the effects of target difficulty on retrieval and consolidation processes.

Wierda SM, Taatgen NA, van Rijn H, Martens S - PLoS ONE (2013)

Grand averages for the ERPs of high-frequency and low-frequency words at lag 2 (A), 7 (B), and 8 (C).The ERPs are time-locked on target onset. Only correct trials were analyzed.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3760916&req=5

pone-0073415-g008: Grand averages for the ERPs of high-frequency and low-frequency words at lag 2 (A), 7 (B), and 8 (C).The ERPs are time-locked on target onset. Only correct trials were analyzed.
Mentions: The EEG data was rereferenced to the mastoid electrodes. In order to remove noise, the data was filtered using a high-pass filter with a cutoff frequency of 1 Hz (24 dB/oct) and a low-pass filter with a cutoff frequency of 40 Hz (24 dB/oct). As we were interested in the activity at the parietal sites, data were then pooled over the parietal electrodes CPz, P1, P2, POz, and Pz. Next, the data were divided in T2-timelocked segments of one second (−200 ms to 800 ms). The 200 ms before onset of T2 served as baseline activity. Segments containing eye-blinks were excluded from analysis. Also, if the difference in voltage between the minimum and maximum data-point in a segments exceeded 100 µVolt, the segment was excluded. The final exclusion criterion was when the difference between two successive data-points exceeded 50 µVolt. In total, three segments were excluded. The grand averages for lag 2, 7, and 8 are shown in Figure 8a, Figure8b, Figure 8c, respectively.

Bottom Line: The opposite effect was found for T2.Our results were replicated in a subsequent ERP study.However, it was successfully accounted for by the threaded-cognition model, thus providing an explanation in terms of attentional control.

View Article: PubMed Central - PubMed

Affiliation: Neuroimaging Center, University of Groningen, Groningen, The Netherlands ; Department of Neuroscience, University Medical Center Groningen, Groningen, The Netherlands.

ABSTRACT

Background: When a second target (T2) is presented in close succession of a first target (T1) within a stream of non-targets, people often fail to detect T2-a deficit known as the attentional blink (AB). Two types of theories can be distinguished that have tried to account for this phenomenon. Whereas attentional-control theories suggest that protection of consolidation processes induces the AB, limited-resource theories claim that the AB is caused by a lack of resources. According to the latter type of theories, increasing difficulty of one or both targets should increase the magnitude of the AB. Similarly, attentional-control theories predict that a difficult T1 increases the AB due to prolonged processing. However, the prediction for T2 is not as straightforward. Prolonged processing of T2 could cause conflicts and increase the AB. However, if consolidation of T2 is postponed without loss of identity, the AB might be attenuated.

Methodology/principal findings: Participants performed an AB task that consisted of a stream of distractor non-words and two target words. Difficulty of T1 and T2 was manipulated by varying word-frequency. Overall performance for high-frequency words was better than for low-frequency words. When T1 was highly frequent, the AB was reduced. The opposite effect was found for T2. When T2 was highly frequent, performance during the AB period was relatively worse than for a low-frequency T2. A threaded-cognition model of the AB was presented that simulated the observed pattern of behavior by taking changes in the time-course of retrieval and consolidation processes into account. Our results were replicated in a subsequent ERP study.

Conclusions/significance: The finding that a difficult low-frequency T2 reduces the magnitude of the AB is at odds with limited-resource accounts of the AB. However, it was successfully accounted for by the threaded-cognition model, thus providing an explanation in terms of attentional control.

Show MeSH
Related in: MedlinePlus