The disengagement of visual attention in the gap paradigm across adolescence
The disengagement of visual attention in the gap paradigm across adolescence
S. Van der Stigchel 0 1 2
R. S. Hessels 0 1 2
J. C. van Elst 0 1 2
C. Kemner 0 1 2
0 Brain Centre Rudolf Magnus, University Medical Center , Utrecht , The Netherlands
1 Developmental Psychology, Utrecht University , Utrecht , The Netherlands
2 Department of Experimental Psychology, Helmholtz Institute, Utrecht University , Heidelberglaan 1, 3584 CS Utrecht , The Netherlands
3 S. Van der Stigchel
Attentional disengagement is important for successful interaction with our environment. The efficiency of attentional disengagement is commonly assessed using the gap paradigm. There is, however, a sharp contrast between the number of studies applying the gap paradigm to clinical populations and the knowledge about the underlying developmental trajectory of the gap effect. The aim of the present study was, therefore, to investigate attentional disengagement in a group of children aged 9-15. Besides the typically deployed gap and the overlap conditions, we also added a baseline condition in which the fixation point was removed at the moment that the target appeared. This allowed us to reveal the appropriate experimental conditions to unravel possible developmental differences. Correlational analyses showed that the size of the gap effect became smaller with increasing age, but only for the difference between the gap and the overlap conditions. This shows that there is a gradual increase in the capacity to disengage visual attention with increasing age, but that this effect only becomes apparent when the gap and the overlap conditions are compared. The gradual decrease of the gap effect with increasing age provides additional evidence that the attentional system becomes more efficient with increasing age and that this is a gradual process.
Gap effect; Eye movements; Development; Attentional disengagement
Introduction
Because we can only execute one eye movement at a time,
there is a continuous decision process to determine to which
location the next eye movement will be executed. Research
has shown that there are different stages of this decision
process that show a developmental trajectory. In the present
study, we will focus on the disengagement of visual
attention. Because of the obligatory link between attention and
eye movements
(Rizzolatti et al. 1994)
, the disengagement
of attention from the current fixation location is necessary
in order to program the next saccade. The efficiency of this
disengagement can be measured using the gap paradigm, in
which participants have the task to execute a saccade from
a central fixation point to a peripheral target. By removing
the fixation point before the onset of the target, the
participant can already disengage from the fixation point before the
target appears. This early disengagement results in a
reduction in saccade latency compared to when the fixation point
remains present
(the so called “gap effect”, Saslow 1967)
.
This robust reduction in latency is independent of advance
knowledge of the location of the saccade target (Walker et al.
1995).
There is now ample evidence that the size of the gap
effect is larger for children compared to adults
(Cohen and
Ross 1977, 1978; Klein 2001)
, meaning that it takes children
longer to disengage attention than adults. This result shows
that the attentional system becomes more efficient during
childhood. Attentional disengagement is important for
successful interaction with our environment, such as being safe
in traffic or during child–parent interactions. Because of the
importance of attentional disengagement, the gap effect has
been studied in various clinical populations, such as children
with autism spectrum disorder
(Fischer et al. 2014;
Goldberg et al. 2002; Landry and Bryson 2004; van der Geest
et al. 2001)
and children with ADHD
(Cairney et al. 2001;
Munoz et al. 2003)
. Especially for studies on children with
autism spectrum disorder, the results have been
inconclusive, with some studies showing a smaller gap effect (van
der Geest et al. 2001), other studies reporting a larger gap
effect
(Landry and Bryson 2004)
, and other studies showing
no modulation of the gap effect in children with autism
spectrum disorder compared to controls
(Goldberg et al. 2002)
.
The inconsistent clinical results discussed above
emphasize the need for more knowledge about the mechanisms
underlying the gap effect. There is namely a sharp contrast
between the number of studies applying the gap paradigm to
clinical populations and the knowledge about the
developmental trajectory of the gap effect. Although the differences
between children and adults in the size of the gap effect are
well established
(Cohen and Ross 1977, 1978; Klein 2001)
,
findings regarding the exact developmental trajectory of the
gap effect during development have been largely
inconsistent. Whereas some studies observed no correlation between
age and the gap effect in particip (...truncated)