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Reward saccade

Hyoung F Kim, Hidetoshi Amita, Okihide Hikosaka
The striatum controls behavior in two ways: facilitation and suppression through the direct and indirect pathways, respectively. However, it is still unclear what information is processed in these pathways. To address this question, we studied two pathways originating from the primate caudate tail (CDt). We found that the CDt innervated the caudal-dorsal-lateral part of the substantia nigra pars reticulata (cdlSNr), directly or indirectly through the caudal-ventral part of the globus pallidus externus (cvGPe)...
May 17, 2017: Neuron
Yoshiko Kojima, Robijanto Soetedjo
In this study we tested whether a selective reward could affect the adaptation of saccadic eye movements in monkeys. We induced the adaptation of saccades by displacing the target of a horizontal saccade vertically as the eye moved toward it, thereby creating an apparent vertical dysmetria. The repeated upward target displacement caused the originally horizontal saccade to gradually deviate upward over the course of several hundred trials. We induced this directional adaptation in both right- and leftward saccades in every experiment (n=20)...
May 10, 2017: Neuroscience
Masaharu Yasuda, Okihide Hikosaka
We reach a goal immediately after detecting the target, or later by withholding the immediate action. Each time, we choose one of these actions by suppressing the other. How does the brain control these antagonistic actions? We hypothesized that the output of basal ganglia (BG), substantia nigra pars reticulata (SNr), suppresses antagonistic oculomotor signals by sending strong inhibitory output to superior colliculus (SC). To test this hypothesis, we trained monkeys to perform two kinds of saccade task: Immediate (visually guided) and delayed (visually-withheld but memory-guided) saccade tasks...
2017: Frontiers in Neuroanatomy
Nicholas C Foley, Simon P Kelly, Himanshu Mhatre, Manuel Lopes, Jacqueline Gottlieb
In natural behavior, animals have access to multiple sources of information, but only a few of these sources are relevant for learning and actions. Beyond choosing an appropriate action, making good decisions entails the ability to choose the relevant information, but fundamental questions remain about the brain's information sampling policies. Recent studies described the neural correlates of seeking information about a reward, but it remains unknown whether, and how, neurons encode choices of instrumental information, in contexts in which the information guides subsequent actions...
April 18, 2017: Proceedings of the National Academy of Sciences of the United States of America
Annalisa Tosoni, Giorgia Committeri, Cinzia Calluso, Gaspare Galati
Perceptual discriminations can be strongly biased by the expected reward for a correct decision but the neural mechanisms underlying this influence are still partially unclear. Using functional magnetic resonance imaging (fMRI) during a task requiring to arbitrarily associate a visual stimulus with a specific action, we have recently shown that perceptual decisions are encoded within the same sensory-motor regions responsible for planning and executing specific motor actions. Here we examined whether these regions additionally encode the amount of expected reward for a perceptual decision...
March 6, 2017: European Journal of Neuroscience
Markku Kilpeläinen, Jan Theeuwes
People use eye movements extremely effectively to find objects of interest in a cluttered visual scene. Distracting, task-irrelevant attention capturing regions in the visual field should be avoided as they jeopardize the efficiency of search. In the current study, we used eye tracking to determine whether people are able to avoid making saccades to a predetermined visual area associated with a financial penalty, while making fast and accurate saccades towards stimuli placed near the penalty area. We found that in comparison to the same task without a penalty area, the introduction of a penalty area immediately affected eye movement behaviour: the proportion of saccades to the penalty area was immediately reduced...
2016: PloS One
Ken-Ichi Okada, Yasushi Kobayashi
The pedunculopontine tegmental nucleus (PPTg) in the brainstem plays a role in controlling reinforcement learning and executing conditioned behavior. We previously examined the activity of PPTg neurons in monkeys during a reward-conditioned, visually guided saccade task, and reported that a population of these neurons exhibited tonic responses throughout the task period. These tonic responses might depend on prediction of the upcoming reward, successful execution of the task, or both. Here, we sought to further distinguish these factors and to investigate how each contributes to the tonic neuronal activity of the PPTg...
2016: Frontiers in Systems Neuroscience
Tomoki W Suzuki, Jun Kunimatsu, Masaki Tanaka
Our daily experience of time is strongly influenced by internal states, such as arousal, attention, and mood. However, the underlying neuronal mechanism remains largely unknown. To investigate this, we recorded pupil diameter, which is closely linked to internal factors and neuromodulatory signaling, in monkeys performing the oculomotor version of the time production paradigm. In the self-timed saccade task, animals were required to make a memory-guided saccade during a predetermined time interval following a visual cue...
November 2, 2016: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
Jun Kunimatsu, Masaki Tanaka
The ability to adjust movement timing is essential in daily life. Explorations of the underlying neural mechanisms have reported a gradual increase or decrease in neuronal activity prior to self-timed movements within the cortico-basal ganglia loop. Previous studies in both humans and animals have shown that endogenous dopamine (DA) plays a modulatory role in self-timing. However, the specific site of dopaminergic regulation remains elusive because the systemic application of DA-related substances can directly alter both cortical and subcortical neuronal activities...
September 17, 2016: Neuroscience
Ali Ghazizadeh, Whitney Griggs, Okihide Hikosaka
Among many objects around us, some are more salient than others (i.e., attract our attention automatically). Some objects may be inherently salient (e.g., brighter), while others may become salient by virtue of their ecological relevance through experience. However, the role of ecological experience in automatic attention has not been studied systematically. To address this question, we let subjects (macaque monkeys) view a large number of complex objects (>300), each experienced repeatedly (>5 days) with rewarding, aversive or no outcome association (mere-perceptual exposure)...
2016: Frontiers in Neuroscience
Brónagh McCoy, Jan Theeuwes
The present study examines the extent to which distractors that signal the availability of monetary reward on a given trial affect eye movements. We used a novel eye movement task in which observers had to follow a target around the screen while ignoring distractors presented at varying locations. We examined the effects of reward magnitude and distractor location on a host of oculomotor properties, including saccade latency, amplitude, landing position, curvature, and erroneous saccades towards the distractor...
August 31, 2016: Journal of Neurophysiology
Ali Ghazizadeh, Whitney Griggs, Okihide Hikosaka
For most animals, survival depends on rapid detection of rewarding objects, but search for an object surrounded by many others is known to be difficult and time consuming. However, there is neuronal evidence for robust and rapid differentiation of objects based on their reward history in primates (Hikosaka, Kim, Yasuda, & Yamamoto, 2014). We hypothesized that such robust coding should support efficient search for high-value objects, similar to a pop-out mechanism. To test this hypothesis, we let subjects (n = 4, macaque monkeys) view a large number of complex objects with consistently biased rewards with variable training durations (1, 5, or 30 + days)...
August 1, 2016: Journal of Vision
Céline Paeye, Alexander C Schütz, Karl R Gegenfurtner
We use eye movements to gain information about our visual environment; this information can indirectly be used to affect the environment. Whereas eye movements are affected by explicit rewards such as points or money, it is not clear whether the information gained by finding a hidden target has a similar reward value. Here we tested whether finding a visual target can reinforce eye movements in visual search performed in a noise background, which conforms to natural scene statistics and contains a large number of possible target locations...
August 1, 2016: Journal of Vision
Kinan Muhammed, Sanjay Manohar, Michael Ben Yehuda, Trevor T-J Chong, George Tofaris, Graham Lennox, Marko Bogdanovic, Michele Hu, Masud Husain
Apathy is a debilitating and under-recognized condition that has a significant impact in many neurodegenerative disorders. In Parkinson's disease, it is now known to contribute to worse outcomes and a reduced quality of life for patients and carers, adding to health costs and extending disease burden. However, despite its clinical importance, there remains limited understanding of mechanisms underlying apathy. Here we investigated if insensitivity to reward might be a contributory factor and examined how this relates to severity of clinical symptoms...
October 2016: Brain: a Journal of Neurology
Annegret Meermeier, Svenja Gremmler, Markus Lappe
When we observe a scene, we shift our gaze to different points of interest via saccadic eye movements. Saccades provide high resolution views of objects and are essential for vision. The successful view of an interesting target might constitute a rewarding experience to the oculomotor system. We measured the influence of image content on learning efficiency in saccade control. We compared meaningful pictures to luminance and spatial frequency-matched random noise images in a saccadic adaptation paradigm. In this paradigm a shift of the target during the saccades results in a gradual increase of saccade amplitude...
June 1, 2016: Journal of Vision
Weijie Ye, Shenquan Liu, Xuanliang Liu, Yuguo Yu
Decision-making is a flexible process dependent on the accumulation of various kinds of information; however, the corresponding neural mechanisms are far from clear. We extended a layered model of the frontal eye field to a learning-based model, using computational simulations to explain the cognitive process of choice tasks. The core of this extended model has three aspects: direction-preferred populations that cluster together the neurons with the same orientation preference, rule modules that control different rule-dependent activities, and reward-based synaptic plasticity that modulates connections to flexibly change the decision according to task demands...
September 2016: Neural Networks: the Official Journal of the International Neural Network Society
Chris van der Togt, Liviu Stănişor, Arezoo Pooresmaeili, Larissa Albantakis, Gustavo Deco, Pieter R Roelfsema
How do you make a decision if you do not know the rules of the game? Models of sensory decision-making suggest that choices are slow if evidence is weak, but they may only apply if the subject knows the task rules. Here, we asked how the learning of a new rule influences neuronal activity in the visual (area V1) and frontal cortex (area FEF) of monkeys. We devised a new icon-selection task. On each day, the monkeys saw 2 new icons (small pictures) and learned which one was relevant. We rewarded eye movements to a saccade target connected to the relevant icon with a curve...
August 2016: Cerebral Cortex
Daniel Pearson, Raphaella Osborn, Thomas J Whitford, Michel Failing, Jan Theeuwes, Mike E Le Pelley
Recent research has shown that reward learning can modulate oculomotor and attentional capture by physically salient and task-irrelevant distractor stimuli, even when directing gaze to those stimuli is directly counterproductive to receiving reward. This value-modulated oculomotor capture effect may reflect biased competition in the oculomotor system, such that the relationship between a stimulus feature and reward enhances that feature's representation on an internal priority map. However, it is also possible that this effect is a result of reward reducing the threshold for a saccade to be made to salient items...
October 2016: Attention, Perception & Psychophysics
Joshua I Glaser, Daniel K Wood, Patrick N Lawlor, Pavan Ramkumar, Konrad P Kording, Mark A Segraves
When a saccade is expected to result in a reward, both neural activity in oculomotor areas and the saccade itself (e.g., its vigor and latency) are altered (compared with when no reward is expected). As such, it is unclear whether the correlations of neural activity with reward indicate a representation of reward beyond a movement representation; the modulated neural activity may simply represent the differences in motor output due to expected reward. Here, to distinguish between these possibilities, we trained monkeys to perform a natural scene search task while we recorded from the frontal eye field (FEF)...
August 1, 2016: Journal of Neurophysiology
Nicolas Wattiez, Tymothée Poitou, Sophie Rivaud-Péchoux, Pierre Pouget
The time to initiate a movement can, even implicitly, be influenced by the environment. All primates, including humans, respond faster and with greater accuracy to stimuli that are brighter, louder or associated with larger reward, than to neutral stimuli. Whether this environment also modulates the executive functions which allow ongoing actions to be suppressed remains an issue of debate. In this study, we investigated the implicit learning of spatial selectivity of movement inhibition in humans and macaque monkeys performing a saccade-countermanding task...
July 2016: Experimental Brain Research. Experimentelle Hirnforschung. Expérimentation Cérébrale
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