Allocation Of Spatial Attention Research Articles

Sudden onsets reflexively drive spatial attention, but those that predict reward do more

The sudden appearance of an unexpected object elicits the automatic allocation of spatial attention. Even without eye movements, effortless, but transient, improvements in perception occur at the onset location. Much is known about the consequences of such exogenously elicited shifts of covert attention, but most research has used stimuli that carry very little, if any, additional information. In everyday life, attention is captured by sudden onsets that, due to past experience, alert us to more than just their appearance. An abundance of recent work has shed light on the interaction of associative learning and attention, leading to refinements in current models of attentional control; in this study, we tested two hypotheses concerning the efficacy of meaning-imbued onsets, specifically those that predict reward, to drive the reflexive allocation of covert spatial attention and to improve task performance more generally. First, spatially uninformative, abrupt-onset cues that are predictive of reward may elicit the involuntary allocation of attention more effectively than nonreward-predictive onsets; second, the presence of peripheral cues that are predictive of reward, regardless of validity, may impact global attentional processes in a spatially nonspecific manner. We paired monetary reward with one of two luminance-defined, abrupt-onset cues and measured each cue's ability to modulate performance in a visual task. Replicating research with nonmeaning–imbued stimuli, both kinds of abrupt onsets reflexively improved visual perception at attended, relative to unattended, locations. However, when features of the onset predicted the availability of monetary reward, enhancements in perception become less constrained, spreading rapidly to other task-relevant locations.

Microsaccades: Empirical Research and Methodological Advances - Introduction to Part 1 of the Thematic Special Issue.

Microsaccades: Empirical Research and Methodological Advances - Introduction to Part 1 of the Thematic Special Issue.

A computational paradigm for real-time MEG neurofeedback for dynamic allocation of spatial attention

BackgroundNeurofeedback aids volitional control of one’s own brain activity using non-invasive recordings of brain activity. The applications of neurofeedback include improvement of cognitive performance and treatment of various psychiatric and neurological disorders. During real-time magnetoencephalography (rt-MEG), sensor-level or source-localized brain activity is measured and transformed into a visual feedback cue to the subject. Recent real-time fMRI (rt-fMRI) neurofeedback studies have used pattern recognition techniques to decode and train a brain state to link brain activities and cognitive behaviors. Here, we utilize the real-time decoding technique similar to ones employed in rt-fMRI to analyze time-varying rt-MEG signals.ResultsWe developed a novel rt-MEG method, state-based neurofeedback (sb-NFB), to decode a time-varying brain state, a state signal, from which timings are extracted for neurofeedback training. The approach is entirely data-driven: it uses sensor-level oscillatory activity to find relevant features that best separate the targeted brain states. In a psychophysical task of spatial attention switching, we trained five young, healthy subjects using the sb-NFB method to decrease the time necessary for switch spatial attention from one visual hemifield to the other (referred to as switch time). Training resulted in a decrease in switch time with training. We saw that the activity targeted by the training involved proportional changes in alpha and beta-band oscillations, in sensors at the occipital and parietal regions. We also found that the state signal that encodes whether subjects attend to the left or right visual field effectively switches consistently with the task.ConclusionWe demonstrated the use of the sb-NFB method when the subject learns to increase the speed of shifting covert spatial attention from one visual field to the other. The sb-NFB method can target timing features that would otherwise also include extraneous features such as visual detection and motor response in a simple reaction time task.

Neural mechanisms of impaired executive function in untreated colorectal cancer patients.

e24170 Background: Cancer-related cognitive impairment (CRCI) affects 45% of colorectal cancer (CRC) patients prior to treatment. This study aimed to explore the neural mechanisms of CRCI in this severely understudied population by using a combination of neuropsychological and cognitive neurophysiology assessments. Methods: Newly diagnosed Stage I-IV CRC patients were recruited at a Midwestern tertiary medical center. Enrollment criteria included normal or corrected to normal vision and no prior cancer within 3 years. Healthy comparisons were recruited and demographically-matched to Stage III/IV patients scheduled to receive chemotherapy. Participants completed neuropsychological measures of processing speed, psychomotor speed, executive function, and verbal memory at study baseline. We recorded scalp electroencephalography while participants performed a computer-based cognitive task designed to measure control over spatial attention. Two event-related potentials were measured following presentation of a task-irrelevant spatial cue: (1) N2, a neural correlate of stimulus selection emerging approximately 160 milliseconds after stimulus presentation; and (2) N2pc, a neural correlate of spatial attention allocation emerging approximately 200 milliseconds after stimulus presentation. Results: CRC patients were enrolled within 4-8 weeks following surgery for Stage I (11%), II (31%), and III (35%) CRC; Stage IV patients (23%) started chemotherapy without surgery. Patients (n = 26) and controls (n = 14) were matched on age and gender; patients were trending toward lower education than controls (p = .06). Patients performed worse than controls on executive function assessments (Trials B: p = .049; Stroop: p = .025). N2 amplitudes were smaller in patients than controls (p = 0.032. N2pc amplitudes were larger in patients than controls (p = .092). N2 amplitudes were associated with Stroop interference scores (r = 0.50, p = .068). Conclusions: CRC patients demonstrated impaired executive function performance at baseline. Neurophysiological data suggest impairments may emerge from limited neural resources available for stimulus selection and poor control over spatial attention. Correlations between neurophysiological data and executive function performance suggest participants better able to overcome task-irrelevant interference had relatively more neural resources available for stimulus selection. Overall, these results suggest patients may be limited in their ability to focus their attention on caregiver and health care team instructions. Clinical trial information: NCT03683004 .

Behavioral and neuronal study of inhibition of return in barn owls

Inhibition of return (IOR) is the reduction of detection speed and/or detection accuracy of a target in a recently attended location. This phenomenon, which has been discovered and studied thoroughly in humans, is believed to reflect a brain mechanism for controlling the allocation of spatial attention in a manner that enhances efficient search. Findings showing that IOR is robust, apparent at a very early age and seemingly dependent on midbrain activity suggest that IOR is a universal attentional mechanism in vertebrates. However, studies in non-mammalian species are scarce. To explore this hypothesis comparatively, we tested for IOR in barn owls (Tyto alba) using the classical Posner cueing paradigm. Two barn owls were trained to initiate a trial by fixating on the center of a computer screen and then turning their gaze to the location of a target. A short, non-informative cue appeared before the target, either at a location predicting the target (valid) or a location not predicting the target (invalid). In one barn owl, the response times (RT) to the valid targets compared to the invalid targets shifted from facilitation (lower RTs) to inhibition (higher RTs) when increasing the time lag between the cue and the target. The second owl mostly failed to maintain fixation and responded to the cue before the target onset. However, when including in the analysis only the trials in which the owl maintained fixation, an inhibition in the valid trials could be detected. To search for the neural correlates of IOR, we recorded multiunit responses in the optic tectum (OT) of four head-fixed owls passively viewing a cueing paradigm as in the behavioral experiments. At short cue to target lags (<100 ms), neural responses to the target in the receptive field (RF) were usually enhanced if the cue appeared earlier inside the RF (valid) and were suppressed if the cue appeared earlier outside the RF (invalid). This was reversed at longer lags: neural responses were suppressed in the valid conditions and were unaffected in the invalid conditions. The findings support the notion that IOR is a basic mechanism in the evolution of vertebrate behavior and suggest that the effect appears as a result of the interaction between lateral and forward inhibition in the tectal circuitry.

Different neural activations for an approaching friend versus stranger: Linking personal space to numerical cognition.

IntroductionTypically, humans place themselves at a preferred distance from others. This distance is known to characterize human spatial behavior. Here, we focused on neurocognitive conditions that may affect interpersonal distances. The current study investigated whether neurocognitive deficiencies in numerical and spatial knowledge may affect social perception and modulate personal space.MethodIn an event‐related potential (ERP) study, university students with developmental dyscalculia (DD) and typically developing control participants were given a computerized version of the comfortable interpersonal distance task, in which participants were instructed to press the spacebar when they began to feel uncomfortable by the approach of a virtual protagonist.ResultsResults showed that students with deficiencies in numerical and spatial skills (i.e., DD) demonstrated reduced variability in their preferred distance from an approaching friend. Importantly, DD showed decreased amplitude of the N1 wave in the friend condition.ConclusionThese results suggest that people coping with deficiencies in spatial cognition have a less efficient allocation of spatial attention in the service of processing personal distances. Accordingly, the study highlights the fundamental role of spatial neurocognition in organizing social space.

Body Dissatisfaction Enhances Awareness and Facilitates the Consolidation of Body-Related Words During Rapid Serial Visual Presentation.

Attentional biases have received considerable focus in research on cognitive biases and body dissatisfaction (BD). However, most work has focused on spatial allocation of attention. The current two experiments employed a rapid serial visual presentation (RSVP) task to investigate attention bias to body-related words in the temporal domain among young females with high and low BD. During this task, there were two targets presented in the same stimulus stream. The first target was defined as target one (T1) and the second was defined as target 2 (T2). Participants were asked to identify T2 while ignoring T1 in single task mode or identify both targets in the dual task mode. In the current study, Experiment 1 assessed the stimulus-driven attention of body-related stimuli. Participants were required to identify a target of neutral word (T2) as quickly and accurately as possible while ignoring the preceding target (T1) of neutral, fat-, or thin-related words. As expected, we observed spontaneous attentional blink (AB) effects elicited by both fat- and thin-related T1s among participants with high BD, suggesting enhanced awareness of body-related stimuli even when this information does not have to be identified. Such effects did not emerge among participants without BD. Experimental 2 investigated the goal-directed attention of body-related stimuli, during which participants needed to identify both the T1 and neutral T2. Participants with BD showed reduced AB effects after both fat- and thin-related T1, suggesting facilitated consolidation of body-related information in goal-directed attention among participants with BD. These findings have important clinical implications that it provided insight for creating more accurate attention bias modification (ABM) task aiming at reducing and preventing BD among young females.

The influence of traumatic brain injury on the allocation of vertical spatial attention

ABSTRACTObjective: Research on impairments of spatial attention has primarily investigated hemispatial neglect in brain-lesioned patients, revealing decrements in the allocation of attention to right versus left egocentric or allocentric hemispace. Whereas head trauma might injure those parts of the brain that allocate vertical attention, little is known about the influence of trauma on the allocation of visuospatial attention in vertical space. Thus, the goal of this study was to learn if chronic moderate-to-severe traumatic brain injury (m/sTBI) alters the allocation of vertical visuospatial attention as assessed by the Attention Network Task (ANT). The ANT assesses the influence of Posner-type spatial cues and distractors using an Eriksen flanker task.Methods: 12 chronic m/sTBI patients and 12 demographically-matched neurologically-healthy controls (HCs) completed a version of the ANT wherein trials were coded for cue and target locations above and below central visual fixation. Trial-wise reaction times (RT) and accuracy were subjected to mixed-model ANOVAs and planned contrasts.Results: These data were subject to secondary analyses, which revealed that across groups, median RTs were significantly faster when targets occurred above than below the central visual fixation (p < .01); however, only HCs’ error rates differed as a function of target altitude. Unlike controls, m/sTBI survivors did not exhibit the anticipated upward error-rate attentional bias.Conclusions: As alteration of spatial attention can be a major cause of disability, present findings suggest that m/sTBI survivors exhibit this loss of normal upward attentional bias. Future studies are need to learn if these patients might benefit from treatment.

Improved Accuracy on Lateralized Spatial Judgments in Healthy Aging.

Healthy young adults often demonstrate a leftward spatial bias called "pseudoneglect" which often diminishes with aging. One hypothesis for this phenomenon is an age-related deterioration in right hemisphere functions (right hemi-aging). If true, then a greater rightward bias should be evident on all spatial attention tasks regardless of content. Another hypothesis is a decrease in asymmetrical hemispheric activation with age (HAROLD). If true, older participants may show reduced bias in all spatial tasks, regardless of leftward or rightward biasing of specific spatial content. Seventy right-handed healthy participants, 33 younger (21-40) and 37 older (60-78), were asked to bisect solid and character-letter lines as well as to perform left and right trisections of solid lines. Both groups deviated toward the left on solid line bisections and left trisections. Both groups deviated toward the right on right trisections and character line bisections. In all tasks, the older participants were more accurate than the younger participants. The finding that older participants were more accurate than younger participants across all bisection and trisection conditions suggests a decrease in the asymmetrical hemispheric activation of these specialized networks important in the allocation of contralateral spatial attention or spatial action intention.

Microsaccades and covert attention: Evidence from a continuous, divided attention task.

A substantial question in understanding expert behavior is isolating where experts look, and which aspects of their environment they process. While tracking the position of gaze provides some insight into this process, our ability to attend covertly to regions of space other than the current point of fixation, severely limits the diagnostic power of such data. Over the past decade, evidence has emerged suggesting that microscopic eye movements present during periods of fixation may be linked to the spatial distribution of covert attention, potentially offering a powerful tool for studying expert behavior. To date, the majority of studies in this field have tested the link under the constraints of a trial by trial, forced-response task. In the current study we sought to examine the effect when participants performed a continuous, divided-attention task, with the hope of bridging the gap to a range of more ecological, real-world tasks. We report various aspects of the eye movement and response data including (i) the relationship between microsaccades and drift correction, (ii) response behavior in brief time periods immediately following a microsaccade, (iii) response behavior briefly preceding a microsaccade. Analysis failed to reveal a link between task accuracy and the direction of a microsaccade. Most striking however, we found evidence for a timelocked relationship between the side of space responded to and the direction of the most recent microsaccade. The paper hence provides preliminary evidence that microsaccades may indeed be used to track the ongoing allocation of spatial attention.

The spatial allocation of attention in an interactive environment

Inattentional blindness methods allow for an unobtrusive measure of the spatial distribution of attention; because subjects do not expect the critical object, they have no reason to devote attention to task-irrelevant regions in anticipation of it. We used inattentional blindness to examine the spatial allocation of attention in an interactive game in which subjects navigated through a dynamic environment and avoided hazards. Subjects were most likely to notice unexpected objects in the areas with the greatest risk of contact with a hazard, and less likely to notice equally proximal objects in inaccessible areas of the display or areas in which hazards no longer posed a threat. These results suggest that both the content of the environment and how a subject can interact with it influence the spatial allocation of attention.

Investigating the role of exogenous cueing on selection history formation.

An abundance of recent empirical data suggest that repeatedly allocating visual attention to task-relevant and/or reward-predicting features in the visual world engenders an attentional bias for these frequently attended stimuli, even when they become task irrelevant and no longer predict reward. In short, attentional selection in the past hinders voluntary control of attention in the present. But do such enduring attentional biases rely on a history of voluntary, goal-directed attentional selection, or can they be generated through involuntary, effortless attentional allocation? An abrupt visual onset triggers such a reflexive allocation of covert spatial attention to its location in the visual field, automatically modulating numerous aspects of visual perception. In this Registered Report, we asked whether a selection history that has been reflexively and involuntarily derived (i.e., through abrupt-onset cueing) also interferes with goal-directed attentional control, even in the complete absence of exogenous cues. To build spatially distinct histories of exogenous selection, we presented abrupt-onset cues twice as often at one of two task locations, and as expected, these cues reflexively modulated visual processing: task accuracy increased, and response times (RTs) decreased, when the cue appeared near the target's location, relative to that of the distractor. Upon removal of these cues, however, we found no evidence that exogenous selection history modulated task performance: task accuracy and RTs at the previously most-cued and previously least-cued sides were statistically indistinguishable. Thus, unlike voluntarily directed attention, involuntary attentional allocation may not be sufficient to engender historically contingent selection biases.

Filtering performance in visual working memory is improved by reducing early spatial attention to the distractors.

We investigated the underlying processes that enable improving filtering irrelevant items from entering visual working memory (WM). To this end, participants performed a bilateral change-detection task in which either targets or targets along with distractors (i.e., the filtering condition) appeared in the memory array while ERPs were recorded. In the cue-present condition, we provided a spatial cue coupled with a temporal cue regarding where and when the distractors would appear. On some of the filtering trials, after the offset of the memory array, task-irrelevant probes were briefly flashed either at the locations of the targets or at the locations of the distractors. This enabled measuring whether reactivating the filtering settings resulted in reducing spatial attentional resources to the distractors, allocating additional spatial attentional resources to the targets, or both, as was measured by the P1/N1 amplitude. Results revealed that, relative to the cue-absent condition, in the cue-present condition the P1/N1 amplitude was reduced for probes at the distractors and was similar for probes at the targets. In addition, the reduction in the P1/N1 amplitude was accompanied by a reduced filtering cost in accuracy performance in the cue-present condition relative to the cue-absent condition. These findings suggest that reactivating the distractor filtering settings improved filtering performance in visual WM by reducing the allocation of spatial attention to the distractors already at early processing stages, and not by allocating additional spatial attentional resources to the targets.

Phase shifts in high-beta- and low-gamma-band local field potentials predict the focus of visual spatial attention.

The local field potential (LFP) contains rich information about activity in local neuronal populations. However, it has been challenging to establish direct links between LFP modulations and task-relevant behavior or cognitive processes, such as attention. We sought to determine whether LFP amplitude or phase modulations are predictive of the allocation of visual spatial attention. LFPs were recorded simultaneously in multiple early visual brain structures of alert macaque monkeys performing attention-demanding detection and discrimination tasks. Attention directed toward the receptive field of recorded neurons generated systematically larger phase shifts in high-beta- and low-gamma-frequency LFPs compared with LFP phase shifts on trials in which attention was directed away from the receptive field. This attention-mediated temporal advance corresponded to ~10 ms. LFP phase shifts also correlated with reaction times when monkeys were engaged in the tasks. Importantly, attentional modulation of LFP phase was consistent across monkeys, tasks, visual brain structures, and cortical layers. In contrast, attentional modulation of LFP amplitude varied across frequency bands, visual structures/layers, and tasks. Because LFP phase shifts were robust, consistent, and predictive of spatial attention, they could serve as a reliable marker for attention signals in the brain. NEW & NOTEWORTHY Local field potentials (LFPs) reflect the activity of spatially localized populations of neurons. Whether alterations in LFP activity are indicative of cognitive processes, such as attention, is unclear. We found that shifts in the phase of LFPs measured in multiple visual brain areas reliably predicted the focus of spatial attention. LFP phase shifts could therefore serve as a marker for behaviorally relevant attention signals in the brain.

The Influence of Focused and Sustained Spatial Attention on the Allocation of Spatial Attention.

The objective of this study was to evaluate the impact of directed and sustained attention on the allocation of visuospatial attention. Healthy people often have left lateral and upward vertical spatial attentional biases. However, it is not known whether there will be an increase in bias toward the attended portion of the stimulus when volitional spatial attention is allocated to a portion of a stimulus, whether there are asymmetrical spatial alterations of these biases, and how sustained attention influences these biases. We assessed spatial bias in 36 healthy, right-handed participants using a variant of horizontal and vertical line bisections. Participants were asked to focus on one or the other end of vertical or horizontal lines or entire vertical or horizontal lines, and then to bisect the line either immediately or after a 20 second delay. We found a significant main effect of attentional focus and an interaction between attentional focus and prolonged viewing with delayed bisection. Focusing on a certain portion of the line resulting in a significant deviation toward the attended portion and prolonged viewing of the line prior to bisection significantly enhanced the degree of deviation toward the attended portion. The enhanced bias with directed and sustained attention may be useful modifications of the line bisection test, particularly in clinical populations. Thus, future studies should determine whether prolonged viewing with delayed bisection and spatially focused attention reveals attentional biases in patients with hemispheric lesions who perform normally on the traditional line bisection test. (JINS, 2019, 25, 65-71).

Directing Voluntary Temporal Attention Increases Fixational Stability.

Our visual input is constantly changing, but not all moments are equally relevant. Visual temporal attention, the prioritization of visual information at specific points in time, increases perceptual sensitivity at behaviorally relevant times. The dynamic processes underlying this increase are unclear. During fixation, humans make small eye movements called microsaccades, and inhibiting microsaccades improves perception of brief stimuli. Here, we investigated whether temporal attention changes the pattern of microsaccades in anticipation of brief stimuli. Human observers (female and male) judged stimuli presented within a short sequence. Observers were given either an informative precue to attend to one of the stimuli, which was likely to be probed, or an uninformative (neutral) precue. We found strong microsaccadic inhibition before the stimulus sequence, likely due to its predictable onset. Critically, this anticipatory inhibition was stronger when the first target in the sequence (T1) was precued (task-relevant) than when the precue was uninformative. Moreover, the timing of the last microsaccade before T1 and the first microsaccade after T1 shifted such that both occurred earlier when T1 was precued than when the precue was uninformative. Finally, the timing of the nearest pre- and post-T1 microsaccades affected task performance. Directing voluntary temporal attention therefore affects microsaccades, helping to stabilize fixation at the most relevant moments over and above the effect of predictability. Just as saccading to a relevant stimulus can be an overt correlate of the allocation of spatial attention, precisely timed gaze stabilization can be an overt correlate of the allocation of temporal attention.SIGNIFICANCE STATEMENT We pay attention at moments in time when a relevant event is likely to occur. Such temporal attention improves our visual perception, but how it does so is not well understood. Here, we discovered a new behavioral correlate of voluntary, or goal-directed, temporal attention. We found that the pattern of small fixational eye movements called microsaccades changes around behaviorally relevant moments in a way that stabilizes the position of the eyes. Microsaccades during a brief visual stimulus can impair perception of that stimulus. Therefore, such fixation stabilization may contribute to the improvement of visual perception at attended times. This link suggests that, in addition to cortical areas, subcortical areas mediating eye movements may be recruited with temporal attention.

Changes in the size of attentional focus modulate the apparent object’s size

Previous research has shown that the allocation of spatial attention at a small region of space increases the apparent size of the adjacent spatial area. In four experiments reported here, we systematically induced either small or large foci of attention and examined how this affects the perceived object’s size. We observed that an increase in the size of the attentional focus consistently decreased the apparent object’s size. This outcome provides new insights into how attention alters appearance.

Age-Related Changes in the Allocation of Vertical Attention.

Healthy individuals often have a leftward and upward attentional spatial bias; however, there is a reduction of this leftward bias with aging. The right hemisphere mediates leftward spatial attention and age-related reduction of right hemispheric activity may account for this reduced leftward bias. The right hemisphere also appears to be responsible for upward bias, and this upward bias might reduce with aging. Alternatively, whereas the dorsal visual stream allocates attention downward, the ventral stream allocates attention upward. Since with aging there is a greater atrophy of the dorsal than ventral stream, older participants may reveal a greater upward bias. The main purpose of this study was to learn if aging influences the vertical allocation of spatial attention. Twenty-six young (17 males; mean age 44.62±2.57 years) and 25 healthy elderly (13 males; mean age 72.04±.98 years), right-handed adults performed line bisections using 24 vertical lines (24 cm long and 2 mm thick) aligned with their midsagittal plane. Older adults had a significantly greater upward bias than did younger adults. Normal upward attentional bias increases with aging, possibly due to an age-related reduction of the dorsal attentional stream that is responsible for the allocation of downward attention. (JINS, 2018, 24, 1121-1124).

Hand Position and Response Assignment Modulate the Activation of the Valence-Space Conceptual Metaphor.

Conceptual metaphor is ubiquitous in language and thought, as we usually reason and talk about abstract concepts in terms of more concrete ones via metaphorical mappings that are hypothesized to arise from our embodied experience. One pervasive example is the conceptual projection of valence onto space, which flexibly recruits the vertical and lateral spatial frames to gain structure (e.g., good is up-bad is down and good is right-bad is left). In the current study, we used a valence judgment task to explore the role that exogenous bodily cues (namely response hand positions) play in the allocation of spatial attention and the modulation of conceptual congruency effects. Experiment 1 showed that congruency effects along the vertical axis are weakened when task conditions (i.e., the use of vertical visual cues, on the one hand, and the horizontal alignment of responses, on the other) draw attention to both the vertical and lateral axes making them simultaneously salient. Experiment 2 evidenced that the vertical alignment of participants' hands while responding to the task-regardless of the location of their dominant hand-facilitates the judgment of positive and negative-valence words, as long as participants respond in a metaphor-congruent manner (i.e., up responses are good and down responses are bad). Overall, these results support the claim that source domain representations are dynamically activated in response to the context and that bodily states are an integral part of that context.

Implicitly-learned spatial attention is unimpaired in patients with Parkinson's disease

Extensive research has examined how current goals influence spatial attention. Yet the allocation of spatial attention is also guided by previous experience, which may induce consistent spatial preferences when a visual search target is frequently found in one region of space. Here, we examined the role of the dopaminergic system in acquiring and maintaining location probability learning. We tested Parkinson's patients and age-matched controls in a difficult visual search task in two sessions. In Session 1, unbeknownst to the participants, the target appeared most often in one quadrant in an early, training phase of the experiment. The target was randomly located in a later, testing phase. Both Parkinson's patients and controls acquired an attentional preference toward the high-probability quadrant during training that persisted in the testing phase. Learning yielded a large reduction in response time (345 ms) in Parkinson's patients, and this effect was highly significant. In Session 2, administered several days later, the target's high-probability quadrant changed. Both groups acquired a new preference for Session 2's high-probability quadrant, demonstrating reversal learning. These findings contrast with previously observed deficits in PD in acquiring probabilistic learning and contextual cueing. This result suggests that not all habit-like behaviors depend on the basal ganglia and the dopaminergic system. Instead, preservation of location probability learning may compensate for other types of attentional deficits in PD.