scholarly journals The spatial signal in area LIP is not an obligatory correlate of perceptual evidence during informed saccadic choices

2021 ◽  
Author(s):  
Joshua A Seideman ◽  
Terrence R Stanford ◽  
Emilio Salinas

The lateral intraparietal area (LIP) contains spatially selective neurons that are partly responsible for determining where to look next, and are thought to serve a variety of sensory, motor planning, and cognitive control functions within this role1,2,3. Notably, according to numerous studies in monkeys4,5,6,7,8,9,10,11,12, area LIP implements a fundamental perceptual process, the gradual accumulation of sensory evidence in favor of one choice (e.g., look left) over another (look right), which manifests as a slowly developing spatial signal during a motion discrimination task. However, according to recent inactivation experiments13,14, this signal is unnecessary for accurate task performance. Here we reconcile these contradictory findings. We designed an urgent version of the motion discrimination task in which there is no systematic lag between the perceptual evaluation and the motor action reporting it, and such that the evolution of the subject’s choice can be tracked millisecond by millisecond15,16,17,18. We found that while choice accuracy increased steeply with increasing sensory evidence, at the same time, the spatial signal became progressively weaker, as if it hindered performance. In contrast, in a similarly urgent task in which the discriminated stimuli and the choice targets were spatially coincident, the neural signal seemed to facilitate performance. The data suggest that the ramping activity in area LIP traditionally interpreted as evidence accumulation likely corresponds to a slow, post-decision shift of spatial attention from one location (where the motion occurs) to another (where the eyes land).

2019 ◽  
Author(s):  
Joshua A. Seideman ◽  
Emilio Salinas ◽  
Terrence R. Stanford

The lateral intraparietal cortex (LIP) contributes to visuomotor transformations for determining where to look next. However, its spatial selectivity can signify attentional priority, motor planning, perceptual discrimination, or other mechanisms. Resolving how this LIP signal influences a perceptually guided choice requires knowing exactly when such signal arises and when the perceptual evaluation informs behavior. To achieve this, we recorded single-neuron activity while monkeys performed an urgent choice task for which the perceptual evaluation’s progress can be tracked millisecond by millisecond. The evoked presaccadic responses were strong, exhibited modest motor preference, and were only weakly modulated by sensory evidence. This modulation was remarkable, though, in that its time course preceded and paralleled that of behavioral performance (choice accuracy), and it closely resembled the statistical definition of confidence. The results indicate that, as the choice process unfolds, LIP dynamically combines attentional, motor, and perceptual signals, the former being much stronger than the latter.


2019 ◽  
Author(s):  
Nadim A. A. Atiya ◽  
Arkady Zgonnikov ◽  
Martin Schoemann ◽  
Stefan Scherbaum ◽  
Denis O’Hora ◽  
...  

AbstractDecisions are occasionally accompanied by changes-of-mind. While considered a hallmark of cognitive flexibility, the mechanisms underlying changes-of-mind remain elusive. Previous studies on perceptual decision making have focused on changes-of-mind that are primarily driven by the accumulation of additional noisy sensory evidence after the initial decision. In a motion discrimination task, we demonstrate that changes-of-mind can occur even in the absence of additional evidence after the initial decision. Unlike previous studies of changes-of-mind, the majority of changes-of-mind in our experiment occurred in trials with prolonged initial response times. This suggests a distinct mechanism underlying such changes. Using a neural circuit model of decision uncertainty and change-of-mind behaviour, we demonstrate that this phenomenon is associated with top-down signals mediated by an uncertainty-monitoring neural population. Such a mechanism is consistent with recent neurophysiological evidence showing a link between changes-of-mind and elevated top-down neural activity. Our model explains the long response times associated with changes-of-mind through high decision uncertainty levels in such trials, and accounts for the observed motor response trajectories. Overall, our work provides a computational framework that explains changes-of-mind in the absence of new post-decision evidence.Authors SummaryWe used limited availability of sensory evidence during a standard motion discrimination task, and demonstrated that changes-of-mind could occur long after sensory information was no longer available. Unlike previous studies, our experiment further indicated that changes-of-mind were strongly linked to slow response time. We used a reduced version of a previously developed neural computational model of decision uncertainty and change-of-mind to account for these experimental observations. Importantly, our model showed that the replication of these experimental results required a strong link between change-of-mind and high decision uncertainty (i.e. low decision confidence), supporting the notion that change-of-mind are related to decision uncertainty or confidence.


2018 ◽  
Vol 120 (1) ◽  
pp. 239-249 ◽  
Author(s):  
James E. Gehringer ◽  
David J. Arpin ◽  
Elizabeth Heinrichs-Graham ◽  
Tony W. Wilson ◽  
Max J. Kurz

Although it is well appreciated that practicing a motor task updates the associated internal model, it is still unknown how the cortical oscillations linked with the motor action change with practice. The present study investigates the short-term changes (e.g., fast motor learning) in the α- and β-event-related desynchronizations (ERD) associated with the production of a motor action. To this end, we used magnetoencephalography to identify changes in the α- and β-ERD in healthy adults after participants practiced a novel isometric ankle plantarflexion target-matching task. After practicing, the participants matched the targets faster and had improved accuracy, faster force production, and a reduced amount of variability in the force output when trying to match the target. Parallel with the behavioral results, the strength of the β-ERD across the motor-planning and execution stages was reduced after practice in the sensorimotor and occipital cortexes. No pre/postpractice changes were found in the α-ERD during motor planning or execution. Together, these outcomes suggest that fast motor learning is associated with a decrease in β-ERD power. The decreased strength likely reflects a more refined motor plan, a reduction in neural resources needed to perform the task, and/or an enhancement of the processes that are involved in the visuomotor transformations that occur before the onset of the motor action. These results may augment the development of neurologically based practice strategies and/or lead to new practice strategies that increase motor learning. NEW & NOTEWORTHY We aimed to determine the effects of practice on the movement-related cortical oscillatory activity. Following practice, we found that the performance of the ankle plantarflexion target-matching task improved and the power of the β-oscillations decreased in the sensorimotor and occipital cortexes. These novel findings capture the β-oscillatory activity changes in the sensorimotor and occipital cortexes that are coupled with behavioral changes to demonstrate the effects of motor learning.


2005 ◽  
Vol 102 (49) ◽  
pp. 17810-17815 ◽  
Author(s):  
A. Sapir ◽  
G. d'Avossa ◽  
M. McAvoy ◽  
G. L. Shulman ◽  
M. Corbetta

2021 ◽  
Vol 7 (35) ◽  
pp. eabf9815
Author(s):  
Luis M. Franco ◽  
Michael J. Goard

During navigation, animals often use recognition of familiar environmental contexts to guide motor action selection. The retrosplenial cortex (RSC) receives inputs from both visual cortex and subcortical regions required for spatial memory and projects to motor planning regions. However, it is not known whether RSC is important for associating familiar environmental contexts with specific motor actions. We test this possibility by developing a task in which motor trajectories are chosen based on the context. We find that mice exhibit differential predecision activity in RSC and that optogenetic suppression of RSC activity impairs task performance. Individual RSC neurons encode a range of task variables, often multiplexed with distinct temporal profiles. However, the responses are spatiotemporally organized, with task variables represented along a posterior-to-anterior gradient along RSC during the behavioral performance, consistent with histological characterization. These results reveal an anatomically organized retrosplenial cortical circuit for associating environmental contexts with appropriate motor outputs.


2020 ◽  
Author(s):  
Luis M. Franco ◽  
Michael J. Goard

ABSTRACTDuring navigation, animals often use recognition of familiar environmental contexts to guide motor action selection. The retrosplenial cortex (RSC) receives inputs from both visual cortex and subcortical regions required for spatial memory, and projects to motor planning regions. However, it is not known whether RSC is important for associating familiar environmental contexts with specific motor actions. Here, we test this possibility by developing a task in which trajectories are chosen based on the context. We find that mice exhibit differential pre-decision activity in RSC, and that optogenetic suppression of RSC activity impairs task performance. Individual RSC neurons encode a range of task variables, often multiplexed with distinct temporal profiles. However, the responses are spatiotemporally organized, with task variables represented along a posterior-to-anterior gradient along RSC during the behavioral performance, consistent with histological characterization. These results reveal an anatomically-organized retrosplenial cortical circuit for associating environmental contexts to appropriate motor outputs.


2010 ◽  
Vol 7 (9) ◽  
pp. 871-871
Author(s):  
D. McCormick ◽  
P. Mamassian

2019 ◽  
Author(s):  
Chunyu A. Duan ◽  
Yuxin Pan ◽  
Guofen Ma ◽  
Taotao Zhou ◽  
Siyu Zhang ◽  
...  

ABSTRACTSurvival in a dynamic environment requires animals to plan future actions based on past sensory evidence. However, the neural circuit mechanism underlying this crucial brain function, referred to as motor planning, remains unclear. Here, we employ projection-specific imaging and perturbation methods to investigate the direct pathway linking two key nodes in the motor planning network, the secondary motor cortex (M2) and the midbrain superior colliculus (SC), in mice performing a memory-dependent perceptual decision task. We find dynamic coding of choice information in SC-projecting M2 neurons during motor planning and execution, and disruption of this information by inhibiting M2 terminals in SC selectively impaired decision maintenance. Furthermore, cell-type-specific optogenetic circuit mapping shows that M2 terminals modulate both excitatory and inhibitory SC neurons with balanced synaptic strength. Together, our results reveal the dynamic recruitment of the premotor-collicular pathway as a circuit mechanism for motor planning.


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