Limits...
Effects of reducing the number of candidate tasks in voluntary task switching.

Kleinsorge T, Scheil J - Front Psychol (2015)

Bottom Line: Recently, Demanet and Liefooghe (2014; Experiment 3) reported an experiment on voluntary task switching (VTS) in which the number of candidate tasks to choose from was reduced from 4 to 2 before participants indicated their task choice.This procedure is highly similar to a procedure recently employed by Kleinsorge and Scheil (2013) in a study of cued task switching which yielded evidence for a selective facilitation of task switches by a reduction of the number of tasks to two.In order to examine whether a similar effect would also be observed with VTS, we conceptually replicated the experiment of Demanet and Liefooghe (2014) with an additional control condition in which the number of tasks was not reduced.

View Article: PubMed Central - PubMed

Affiliation: Leibniz Research Centre for Working Environment and Human Factors Dortmund, Germany.

ABSTRACT
Recently, Demanet and Liefooghe (2014; Experiment 3) reported an experiment on voluntary task switching (VTS) in which the number of candidate tasks to choose from was reduced from 4 to 2 before participants indicated their task choice. This procedure was intended to prevent participants from choosing a task in advance of the presentation of a prompt to do so. This procedure is highly similar to a procedure recently employed by Kleinsorge and Scheil (2013) in a study of cued task switching which yielded evidence for a selective facilitation of task switches by a reduction of the number of tasks to two. In order to examine whether a similar effect would also be observed with VTS, we conceptually replicated the experiment of Demanet and Liefooghe (2014) with an additional control condition in which the number of tasks was not reduced. In this experiment, no evidence for a facilitation of task switching could be observed, pointing to a functional divergence between explicit task cues and the internally generated cues involved in VTS. In addition, we observed evidence for a selective advantage of forced switch trials over repetition-possible trials that was largely independent of the duration of the preparation interval. This effect was accompanied by a massive increase of task indication times in conditions with a reduced number of tasks, suggesting that this manipulation resulted in a pronounced change in the way participants performed voluntary task switches.

No MeSH data available.


(A) Schematic illustration of the displays used in a single trial (in chronological order). Asterisk indicates fixation mark. (B) Schematic illustration of the procedure of single trials.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4285012&req=5

Figure 1: (A) Schematic illustration of the displays used in a single trial (in chronological order). Asterisk indicates fixation mark. (B) Schematic illustration of the procedure of single trials.

Mentions: Each trial began with a fixation mark presented for the length of the ERPI. After that, the German names of the four tasks (“Größe” for magnitude, “Gerade” for parity, “Schrift” for font, “Farbe” for color) were visible on the screen until participants made a task indication response by pressing one of four keys (a, s, d, or f, see above) with their left hand. If all four tasks could be chosen, all tasks names were presented in white. In case of a task restriction, the two candidate tasks were presented in white, while the two tasks that could not be chosen were written in gray (cf. Figure 1A). There was no time restriction for task indication responses. In case of disallowed task choices in restricted blocks, participants received error feedback (“This task cannot be selected in this trial!”). After a task had been chosen, a second fixation mark was presented for the duration of the IRSI. After that, the imperative stimulus was presented and remained on the screen until the participant’s response or until 2,500 ms had elapsed (cf. Figure 1B for an illustration of the single trial procedure). In case of RTs higher than the RT deadline of 2,500 ms, RT feedback (‘too slow’) was presented for additional 1,000 ms; in case of an error, error feedback was presented for additional 1,000 ms.


Effects of reducing the number of candidate tasks in voluntary task switching.

Kleinsorge T, Scheil J - Front Psychol (2015)

(A) Schematic illustration of the displays used in a single trial (in chronological order). Asterisk indicates fixation mark. (B) Schematic illustration of the procedure of single trials.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4285012&req=5

Figure 1: (A) Schematic illustration of the displays used in a single trial (in chronological order). Asterisk indicates fixation mark. (B) Schematic illustration of the procedure of single trials.
Mentions: Each trial began with a fixation mark presented for the length of the ERPI. After that, the German names of the four tasks (“Größe” for magnitude, “Gerade” for parity, “Schrift” for font, “Farbe” for color) were visible on the screen until participants made a task indication response by pressing one of four keys (a, s, d, or f, see above) with their left hand. If all four tasks could be chosen, all tasks names were presented in white. In case of a task restriction, the two candidate tasks were presented in white, while the two tasks that could not be chosen were written in gray (cf. Figure 1A). There was no time restriction for task indication responses. In case of disallowed task choices in restricted blocks, participants received error feedback (“This task cannot be selected in this trial!”). After a task had been chosen, a second fixation mark was presented for the duration of the IRSI. After that, the imperative stimulus was presented and remained on the screen until the participant’s response or until 2,500 ms had elapsed (cf. Figure 1B for an illustration of the single trial procedure). In case of RTs higher than the RT deadline of 2,500 ms, RT feedback (‘too slow’) was presented for additional 1,000 ms; in case of an error, error feedback was presented for additional 1,000 ms.

Bottom Line: Recently, Demanet and Liefooghe (2014; Experiment 3) reported an experiment on voluntary task switching (VTS) in which the number of candidate tasks to choose from was reduced from 4 to 2 before participants indicated their task choice.This procedure is highly similar to a procedure recently employed by Kleinsorge and Scheil (2013) in a study of cued task switching which yielded evidence for a selective facilitation of task switches by a reduction of the number of tasks to two.In order to examine whether a similar effect would also be observed with VTS, we conceptually replicated the experiment of Demanet and Liefooghe (2014) with an additional control condition in which the number of tasks was not reduced.

View Article: PubMed Central - PubMed

Affiliation: Leibniz Research Centre for Working Environment and Human Factors Dortmund, Germany.

ABSTRACT
Recently, Demanet and Liefooghe (2014; Experiment 3) reported an experiment on voluntary task switching (VTS) in which the number of candidate tasks to choose from was reduced from 4 to 2 before participants indicated their task choice. This procedure was intended to prevent participants from choosing a task in advance of the presentation of a prompt to do so. This procedure is highly similar to a procedure recently employed by Kleinsorge and Scheil (2013) in a study of cued task switching which yielded evidence for a selective facilitation of task switches by a reduction of the number of tasks to two. In order to examine whether a similar effect would also be observed with VTS, we conceptually replicated the experiment of Demanet and Liefooghe (2014) with an additional control condition in which the number of tasks was not reduced. In this experiment, no evidence for a facilitation of task switching could be observed, pointing to a functional divergence between explicit task cues and the internally generated cues involved in VTS. In addition, we observed evidence for a selective advantage of forced switch trials over repetition-possible trials that was largely independent of the duration of the preparation interval. This effect was accompanied by a massive increase of task indication times in conditions with a reduced number of tasks, suggesting that this manipulation resulted in a pronounced change in the way participants performed voluntary task switches.

No MeSH data available.