Puntiroli, Michael

2019-3-27, Born, Sabine, Puntiroli, Michael, Jordan, Damien, Kerzel, Dirk

Attribute amnesia (Chen & Wyble, 2015, 2016) demonstrates that we may not always be able to spontaneously retrieve a simple attribute of a visual object (e.g., its color) for conscious report, even though the object had just been the target in a visual task. Attribute amnesia has been suggested to reflect a lack of consolidation of the task-irrelevant attribute in visual working memory. Here we tested whether saccadic selection eliminates or attenuates attribute amnesia. Saccade targets have been shown to be preferentially encoded into visual working memory and may therefore be spared. We used simple color pop-out displays, asking participants to indicate the location of the color singleton letter target on each trial either by keypress or by making a saccade toward it. After a couple of trials and unannounced to the participants, we asked for the color and identity of the last target letter on a surprise trial. We found that saccade targets were not spared from attribute amnesia: Participants were as bad in correctly reporting the color in the saccade as in the keypress condition. For letter identity, the effect was attenuated but not abolished when the target was foveated for a short period of time. We argue that the current results do not refute an obligatory coupling between saccadic selection and encoding in visual working memory. However, the encoded information may not necessarily be stored in a manner that is robust enough to persist in the face of a surprise question.

2016-5, Puntiroli, Michael, Kerzel, Dirk, Born, Sabine, Deubel, Heiner, Martin, Szinte

2015, Puntiroli, Michael, Kerzel, Dirk, Born, Sabine

2018-6-1, Puntiroli, Michael, Kerzel, Dirk, Born, Sabine

In the time leading up to a saccade, the saccade target is perceptually enhanced compared to other objects in the visual field. This enhancement is attributed to a shift of spatial attention toward the target. We examined whether the presence of visual objects is critical for the perceptual enhancement at the saccade target to occur. We hypothesized that attention may need an object to focus on in order to be effective. We conducted four experiments using a dual-task design, where participants performed eye movements either to a location demarked by a placeholder or to an empty screen location where no object was displayed. At the same time, they discriminated a probe flashed at the location targeted by the eye movement or at one of two control locations. A strong perceptual advantage at the saccade target location was observed only when placeholders were displayed at the time of probe presentation. The complete absence of placeholders (Experiment 1), the presence of placeholders before but not during probe presentation (Experiment 3), and the presence of objects only around the saccade target (Experiments 3 and 4) led to a strong reduction in the saccade-target benefit. We conclude that placeholders may indeed be necessary to observe presaccadic enhancement at the saccade target. However, this is not because placeholders provide an object to focus attention on, but rather because they produce a masking (or crowding) effect. This detrimental effect is overcome by the presaccadic shift of attention, resulting in heightened perception only at the saccade target object.

2015-8-14, Puntiroli, Michael, Kerzel, Dirk, Born, Sabine

Prior to an eye movement, attention is gradually shifted toward the point where the saccade will land. Our goal was to better understand the allocation of attention in an oculomotor capture paradigm for saccades that go straight to the eye movement target and for saccades that go to a distractor and are followed by corrective saccades to the target (i.e., involuntary saccades). We also sought to test facilitation at the future retinotopic location of target and nontarget objects, with the principal aim of verifying whether the remapping process accounts for the retinal displacement caused by involuntary saccades. Two experiments were run employing a dual-task design, primarily requiring participants to perform saccades toward a target while discriminating an asymmetric cross presented briefly before saccade onset. The results clearly show perceptual facilitation at the target location for goaldirected saccades and at the distractor location when oculomotor capture occurred. Facilitation was observed at a location relating to the remapping of a future saccade landing point, in sequences of oculomotor capture. In contrast, performance remained unaffected at the remapped location of a salient distracting object, which was not looked at. The findings are taken as evidence that presaccadic enhancement occurs prior to involuntary and voluntary saccades alike and that the remapping process also indiscriminatingly accounts for the retinal displacement caused by either.

2014-5, Puntiroli, Michael, Kerzel, Dirk, Born, Sabine

2017-2-1, Puntiroli, Michael, Tandonnet, Christophe, Kerzel, Dirk, Born, Sabine

Hick’s law states that increasing the number of response alternatives increases reaction time. Lawrence and colleagues report an exception to the law, whereby more alternatives lead to shorter saccadic reaction times (SRTs). Usher and McClelland (2001) predict such an anti-Hick’s effect when accuracy is not prioritized in a task, which should result in higher error rates with more response alternatives, and in turn to a shorter right tail of the SRT distribution. In the current study, we aim to replicate the original controversial fndings and we compare them to these predictions by examining error rates and SRT distributions. Two experiments were conducted where participants made rapid eye movements to one of few or many alternatives. In Experiment 1, the saccade target was an onset and participants started either with few or many possible target locations and then alternated between conditions. An anti-Hick’s effect emerged only when participants had started with a small set-size block. In Experiment 2, placeholders were displayed at the possible target locations and independent groups were used. A reliable anti-Hick’s effect in SRTs was observed. However, results did not meet the stated predictions: anticipations and false direction errors were never more frequent when the set size was larger and SRT differences between the two set-size conditions were not more pronounced at the slower end of the distributions. In line with Lawrence and colleagues, we speculate that initial motor preparation, and the subsequent inhibition to counteract a premature response, may induce the anti-Hick’s effect.

2015-5, Puntiroli, Michael, Kerzel, Dirk, Born, Sabine

2013-8, Puntiroli, Michael, Kerzel, Dirk, Born, Sabine