Alisha Siebold | University of Trento (original) (raw)

Papers by Alisha Siebold

Research paper thumbnail of Social salience does not transfer to oculomotor visual search

Research paper thumbnail of Testing the Idea of Privileged Awareness of Self-Relevant Information

Journal of Experimental Psychology: Human Perception and Performance, 2016

Self-relevant information is prioritized in processing. Some have suggested the mechanism driving... more Self-relevant information is prioritized in processing. Some have suggested the mechanism driving this advantage is akin to the automatic prioritization of physically salient stimuli in information processing (Humphreys & Sui, 2015). Here we investigate whether self-relevant information is prioritized for awareness under continuous flash suppression (CFS), as has been found for physical salience. Gabor patches with different orientations were first associated with the labels You or Other. Participants were more accurate in matching the self-relevant association, replicating previous findings of self-prioritization. However, breakthrough into awareness from CFS did not differ between self- and other-associated Gabors. These findings demonstrate that self-relevant information has no privileged access to awareness. Rather than modulating the initial visual processes that precede and lead to awareness, the advantage of self-relevant information may better be characterized as prioritization at later processing stages. (PsycINFO Database Record

Research paper thumbnail of Large Pupils Predict Goal-Driven Eye Movements

Journal of Experimental Psychology: General, 2015

Here we report that large pupils predict fixations of the eye on low-salient, inconspicuous

Research paper thumbnail of Reinstating salience effects over time: the influence of stimulus changes on visual selection behavior over a sequence of eye movements

Attention, perception & psychophysics, 2014

Recently, we showed that salience affects initial saccades only in a static stimulus environment;... more Recently, we showed that salience affects initial saccades only in a static stimulus environment; subsequent saccades were unaffected by salience but, instead, were directed in line with task requirements (Siebold, van Zoest, & Donk, PLoS ONE 6(9): e23552, 2011). Yet multiple studies have shown that people tend to fixate salient regions more often than nonsalient ones when they are looking at images--in particular, when salience is defined by dynamic changes. The goal of the present study was to investigate how oculomotor selection beyond an initial saccade is affected by salience as derived from changing, as opposed to static, stimuli. Observers were presented with displays containing two fixation dots, one target, one distractor, and multiple background elements. They were instructed to fixate on one of the fixation dots and make a speeded eye movement to the target, either directly or preceded by an initial eye movement to the other fixation dot. In Experiment 1, target and distr...

Research paper thumbnail of Large Pupils Predict Goal-Driven Eye Movements

Journal of Experimental Psychology: General, 2015

Here we report that large pupils predict fixations of the eye on low-salient, inconspicuous

Research paper thumbnail of On the importance of relative salience: comparing overt selection behavior of single versus simultaneously presented stimuli

PloS one, 2014

The goal of the current study was to investigate time-dependent effects of the number of targets ... more The goal of the current study was to investigate time-dependent effects of the number of targets presented and its interaction with stimulus salience on oculomotor selection performance. To this end, observers were asked to make a speeded eye movement to a target orientation singleton embedded in a homogeneous background of vertically oriented lines. In Experiment 1, either one or two physically identical targets were presented, whereas in Experiment 2 an additional orientation-based salience manipulation was performed. The results showed that the probability of a singleton being available for selection is reduced in the presence of an identical singleton (Experiment 1) and that this effect is modulated by the salience of the other singleton (Experiment 2). While the absolute orientation contrast of a target relative to the background contributed to the probability that it is available for selection, the crucial factor affecting selection was the relative salience between singletons...

Research paper thumbnail of In defense of the salience map: Salience rather than visibility determines selection

Journal of Experimental Psychology: Human Perception and Performance, 2013

In order to test these two models, we performed an experiment in which participants were instruct... more In order to test these two models, we performed an experiment in which participants were instructed to make a speeded eye movement to any of two orientation singletons presented among a homogeneous set of vertically oriented background lines. One singleton, the fixed singleton, remained identical across conditions, whereas the other singleton, the variable singleton, varied such that its orientation contrast relative to the background lines was either smaller or larger than that of the fixed singleton. The results showed that the proportion of eye movements directed toward the fixed singleton varied substantially depending on the orientation contrast of the variable singleton. A model assuming selection behavior to be determined by relative salience provided a better fit to the individual data than the absolute processing speed model. These findings suggest that relative salience rather than the visibility of an element is crucial in determining temporal variations in oculomotor selection behavior and that an explanation of visual selection behavior is insufficient without the concept of a salience map.

Research paper thumbnail of Oculomotor Evidence for Top-Down Control following the Initial Saccade

PLoS ONE, 2011

The goal of the current study was to investigate how salience-driven and goal-driven processes un... more The goal of the current study was to investigate how salience-driven and goal-driven processes unfold during visual search over multiple eye movements. Eye movements were recorded while observers searched for a target, which was located on (Experiment 1) or defined as (Experiment 2) a specific orientation singleton. This singleton could either be the most, medium, or least salient element in the display. Results were analyzed as a function of response time separately for initial and second eye movements. Irrespective of the search task, initial saccades elicited shortly after the onset of the search display were primarily salience-driven whereas initial saccades elicited after approximately 250 ms were completely unaffected by salience. Initial saccades were increasingly guided in line with task requirements with increasing response times. Second saccades were completely unaffected by salience and were consistently goal-driven, irrespective of response time. These results suggest that stimulus-salience affects the visual system only briefly after a visual image enters the brain and has no effect thereafter.

Research paper thumbnail of Social salience does not transfer to oculomotor visual search

Research paper thumbnail of Testing the Idea of Privileged Awareness of Self-Relevant Information

Journal of Experimental Psychology: Human Perception and Performance, 2016

Self-relevant information is prioritized in processing. Some have suggested the mechanism driving... more Self-relevant information is prioritized in processing. Some have suggested the mechanism driving this advantage is akin to the automatic prioritization of physically salient stimuli in information processing (Humphreys & Sui, 2015). Here we investigate whether self-relevant information is prioritized for awareness under continuous flash suppression (CFS), as has been found for physical salience. Gabor patches with different orientations were first associated with the labels You or Other. Participants were more accurate in matching the self-relevant association, replicating previous findings of self-prioritization. However, breakthrough into awareness from CFS did not differ between self- and other-associated Gabors. These findings demonstrate that self-relevant information has no privileged access to awareness. Rather than modulating the initial visual processes that precede and lead to awareness, the advantage of self-relevant information may better be characterized as prioritization at later processing stages. (PsycINFO Database Record

Research paper thumbnail of Large Pupils Predict Goal-Driven Eye Movements

Journal of Experimental Psychology: General, 2015

Here we report that large pupils predict fixations of the eye on low-salient, inconspicuous

Research paper thumbnail of Reinstating salience effects over time: the influence of stimulus changes on visual selection behavior over a sequence of eye movements

Attention, perception & psychophysics, 2014

Recently, we showed that salience affects initial saccades only in a static stimulus environment;... more Recently, we showed that salience affects initial saccades only in a static stimulus environment; subsequent saccades were unaffected by salience but, instead, were directed in line with task requirements (Siebold, van Zoest, & Donk, PLoS ONE 6(9): e23552, 2011). Yet multiple studies have shown that people tend to fixate salient regions more often than nonsalient ones when they are looking at images--in particular, when salience is defined by dynamic changes. The goal of the present study was to investigate how oculomotor selection beyond an initial saccade is affected by salience as derived from changing, as opposed to static, stimuli. Observers were presented with displays containing two fixation dots, one target, one distractor, and multiple background elements. They were instructed to fixate on one of the fixation dots and make a speeded eye movement to the target, either directly or preceded by an initial eye movement to the other fixation dot. In Experiment 1, target and distr...

Research paper thumbnail of Large Pupils Predict Goal-Driven Eye Movements

Journal of Experimental Psychology: General, 2015

Here we report that large pupils predict fixations of the eye on low-salient, inconspicuous

Research paper thumbnail of On the importance of relative salience: comparing overt selection behavior of single versus simultaneously presented stimuli

PloS one, 2014

The goal of the current study was to investigate time-dependent effects of the number of targets ... more The goal of the current study was to investigate time-dependent effects of the number of targets presented and its interaction with stimulus salience on oculomotor selection performance. To this end, observers were asked to make a speeded eye movement to a target orientation singleton embedded in a homogeneous background of vertically oriented lines. In Experiment 1, either one or two physically identical targets were presented, whereas in Experiment 2 an additional orientation-based salience manipulation was performed. The results showed that the probability of a singleton being available for selection is reduced in the presence of an identical singleton (Experiment 1) and that this effect is modulated by the salience of the other singleton (Experiment 2). While the absolute orientation contrast of a target relative to the background contributed to the probability that it is available for selection, the crucial factor affecting selection was the relative salience between singletons...

Research paper thumbnail of In defense of the salience map: Salience rather than visibility determines selection

Journal of Experimental Psychology: Human Perception and Performance, 2013

In order to test these two models, we performed an experiment in which participants were instruct... more In order to test these two models, we performed an experiment in which participants were instructed to make a speeded eye movement to any of two orientation singletons presented among a homogeneous set of vertically oriented background lines. One singleton, the fixed singleton, remained identical across conditions, whereas the other singleton, the variable singleton, varied such that its orientation contrast relative to the background lines was either smaller or larger than that of the fixed singleton. The results showed that the proportion of eye movements directed toward the fixed singleton varied substantially depending on the orientation contrast of the variable singleton. A model assuming selection behavior to be determined by relative salience provided a better fit to the individual data than the absolute processing speed model. These findings suggest that relative salience rather than the visibility of an element is crucial in determining temporal variations in oculomotor selection behavior and that an explanation of visual selection behavior is insufficient without the concept of a salience map.

Research paper thumbnail of Oculomotor Evidence for Top-Down Control following the Initial Saccade

PLoS ONE, 2011

The goal of the current study was to investigate how salience-driven and goal-driven processes un... more The goal of the current study was to investigate how salience-driven and goal-driven processes unfold during visual search over multiple eye movements. Eye movements were recorded while observers searched for a target, which was located on (Experiment 1) or defined as (Experiment 2) a specific orientation singleton. This singleton could either be the most, medium, or least salient element in the display. Results were analyzed as a function of response time separately for initial and second eye movements. Irrespective of the search task, initial saccades elicited shortly after the onset of the search display were primarily salience-driven whereas initial saccades elicited after approximately 250 ms were completely unaffected by salience. Initial saccades were increasingly guided in line with task requirements with increasing response times. Second saccades were completely unaffected by salience and were consistently goal-driven, irrespective of response time. These results suggest that stimulus-salience affects the visual system only briefly after a visual image enters the brain and has no effect thereafter.