Motor error evaluation appears to be a hierarchically organized process subserved by 2 distinct s... more Motor error evaluation appears to be a hierarchically organized process subserved by 2 distinct systems: a higher level system within medial-frontal cortex responsible for movement outcome evaluation (high-level error evaluation) and a lower level posterior system(s) responsible for the mediation of within-movement errors (low-level error evaluation). While a growing body of evidence suggests that a reinforcement learning system within medial-frontal cortex plays a crucial role in the evaluation of high-level errors made during discrete reaching movements and continuous motor tracking, the role of this system in postural control is currently unclear. Participants learned a postural control task via a feedback-driven trial-and-error shaping process. In line with previous findings, electroencephalographic recordings revealed that feedback about movement outcomes elicited a feedback error-related negativity: a component of the human event-related brain potential associated with high-level outcome evaluation within medial-frontal cortex. Thus, the data provide evidence that a high-level error-evaluation system within medial-frontal cortex plays a key role in learning to control our body posture.
The neural systems that afford our ability to evaluate rewards and punishments are impacted by a ... more The neural systems that afford our ability to evaluate rewards and punishments are impacted by a variety of external factors. Here, we demonstrate that increased cognitive load reduces the functional efficacy of a reward processing system within the human medial-frontal cortex. In our paradigm, two groups of participants used performance feedback to estimate the exact duration of one second while electroencephalographic (EEG) data was recorded. Prior to performing the time estimation task, both groups were instructed to keep their eyes still and avoid blinking in line with well established EEG protocol. However, during performance of the time-estimation task, one of the two groups was provided with trial-to-trial-feedback about their performance on the time-estimation task and their eye movements to induce a higher level of cognitive load relative to participants in the other group who were solely provided with feedback about the accuracy of their temporal estimates. In line with pr...
The Quarterly Journal of Experimental Psychology, 2015
Perceived ownership has been shown to impact a variety of cognitive processes: attention, memory,... more Perceived ownership has been shown to impact a variety of cognitive processes: attention, memory, and-more recently-reward processing. In the present experiment we examined whether or not perceived ownership would interact with the construct of value-the relative worth of an object. Participants completed a simple gambling game in which they gambled either for themselves or for another while electroencephalographic data were recorded. In a key manipulation, gambles for oneself or for another were for either small or large rewards. We tested the hypothesis that value affects the neural response to self-gamble outcomes, but not other-gamble outcomes. Our experimental data revealed that while participants learned the correct response option for both self and other gambles, the reward positivity evoked by wins was impacted by value only when gambling for oneself. Importantly, our findings provide additional evidence for a self-ownership bias in cognitive processing and further demonstrate the insensitivity of the medial-frontal reward system to gambles for another.
Proceedings of the 2011 annual conference extended abstracts on Human factors in computing systems - CHI EA '11, 2011
What Does A Body Know? is a concert work for Digital Ventriloquized Actor (DiVA) and sound clips.... more What Does A Body Know? is a concert work for Digital Ventriloquized Actor (DiVA) and sound clips. A DiVA is a real time gesture-controlled formant-based speech synthesizer using a Cyberglove®, touchglove, and Polhemus Tracker® as the main interfaces. When used in conjunction with the performer's own voice solos and "duets" can be performed in real time.
Motor error evaluation appears to be a hierarchically organized process subserved by 2 distinct s... more Motor error evaluation appears to be a hierarchically organized process subserved by 2 distinct systems: a higher level system within medial-frontal cortex responsible for movement outcome evaluation (high-level error evaluation) and a lower level posterior system(s) responsible for the mediation of within-movement errors (low-level error evaluation). While a growing body of evidence suggests that a reinforcement learning system within medial-frontal cortex plays a crucial role in the evaluation of high-level errors made during discrete reaching movements and continuous motor tracking, the role of this system in postural control is currently unclear. Participants learned a postural control task via a feedback-driven trial-and-error shaping process. In line with previous findings, electroencephalographic recordings revealed that feedback about movement outcomes elicited a feedback error-related negativity: a component of the human event-related brain potential associated with high-level outcome evaluation within medial-frontal cortex. Thus, the data provide evidence that a high-level error-evaluation system within medial-frontal cortex plays a key role in learning to control our body posture.
To maximize reward, we are faced with the dilemma of having to balance the exploration of new res... more To maximize reward, we are faced with the dilemma of having to balance the exploration of new response options and the exploitation of previous choices. Here, we sought to determine if the event-related brain potential (ERP) in the P300 time range is sensitive to decisions to explore or exploit within the context of a sequential risk-taking task. Specifically, the task we used required participants to continually explore their options-whether they should "push their luck" and keep gambling or "take the money and run" and collect their winnings. Our behavioral analysis yielded two distinct distributions of response times: a larger group of short-decision times and a smaller group of long-decision times. Interestingly, these data suggest that participants adopted one of two modes of control on any given trial: a mode where they quickly decided to keep gambling (i.e. exploit), and a mode where they deliberated whether to the take the money they had already won or continue gambling (i.e. explore). Importantly, we found that the amplitude of the ERP in the P300 time range was larger for explorative decisions than for exploitative decisions and, further, was correlated with decision time. Our results are consistent with a recent theoretical account that links changes in ERP amplitude in the P300 time range with phasic activity of the locus coeruleus-norepinephrine system and decisions to engage in exploratory behavior.
Motor error evaluation appears to be a hierarchically organized process subserved by 2 distinct s... more Motor error evaluation appears to be a hierarchically organized process subserved by 2 distinct systems: a higher level system within medial-frontal cortex responsible for movement outcome evaluation (high-level error evaluation) and a lower level posterior system(s) responsible for the mediation of within-movement errors (low-level error evaluation). While a growing body of evidence suggests that a reinforcement learning system within medial-frontal cortex plays a crucial role in the evaluation of high-level errors made during discrete reaching movements and continuous motor tracking, the role of this system in postural control is currently unclear. Participants learned a postural control task via a feedback-driven trial-and-error shaping process. In line with previous findings, electroencephalographic recordings revealed that feedback about movement outcomes elicited a feedback error-related negativity: a component of the human event-related brain potential associated with high-level outcome evaluation within medial-frontal cortex. Thus, the data provide evidence that a high-level error-evaluation system within medial-frontal cortex plays a key role in learning to control our body posture.
The neural systems that afford our ability to evaluate rewards and punishments are impacted by a ... more The neural systems that afford our ability to evaluate rewards and punishments are impacted by a variety of external factors. Here, we demonstrate that increased cognitive load reduces the functional efficacy of a reward processing system within the human medial-frontal cortex. In our paradigm, two groups of participants used performance feedback to estimate the exact duration of one second while electroencephalographic (EEG) data was recorded. Prior to performing the time estimation task, both groups were instructed to keep their eyes still and avoid blinking in line with well established EEG protocol. However, during performance of the time-estimation task, one of the two groups was provided with trial-to-trial-feedback about their performance on the time-estimation task and their eye movements to induce a higher level of cognitive load relative to participants in the other group who were solely provided with feedback about the accuracy of their temporal estimates. In line with pr...
The Quarterly Journal of Experimental Psychology, 2015
Perceived ownership has been shown to impact a variety of cognitive processes: attention, memory,... more Perceived ownership has been shown to impact a variety of cognitive processes: attention, memory, and-more recently-reward processing. In the present experiment we examined whether or not perceived ownership would interact with the construct of value-the relative worth of an object. Participants completed a simple gambling game in which they gambled either for themselves or for another while electroencephalographic data were recorded. In a key manipulation, gambles for oneself or for another were for either small or large rewards. We tested the hypothesis that value affects the neural response to self-gamble outcomes, but not other-gamble outcomes. Our experimental data revealed that while participants learned the correct response option for both self and other gambles, the reward positivity evoked by wins was impacted by value only when gambling for oneself. Importantly, our findings provide additional evidence for a self-ownership bias in cognitive processing and further demonstrate the insensitivity of the medial-frontal reward system to gambles for another.
Proceedings of the 2011 annual conference extended abstracts on Human factors in computing systems - CHI EA '11, 2011
What Does A Body Know? is a concert work for Digital Ventriloquized Actor (DiVA) and sound clips.... more What Does A Body Know? is a concert work for Digital Ventriloquized Actor (DiVA) and sound clips. A DiVA is a real time gesture-controlled formant-based speech synthesizer using a Cyberglove®, touchglove, and Polhemus Tracker® as the main interfaces. When used in conjunction with the performer's own voice solos and "duets" can be performed in real time.
Motor error evaluation appears to be a hierarchically organized process subserved by 2 distinct s... more Motor error evaluation appears to be a hierarchically organized process subserved by 2 distinct systems: a higher level system within medial-frontal cortex responsible for movement outcome evaluation (high-level error evaluation) and a lower level posterior system(s) responsible for the mediation of within-movement errors (low-level error evaluation). While a growing body of evidence suggests that a reinforcement learning system within medial-frontal cortex plays a crucial role in the evaluation of high-level errors made during discrete reaching movements and continuous motor tracking, the role of this system in postural control is currently unclear. Participants learned a postural control task via a feedback-driven trial-and-error shaping process. In line with previous findings, electroencephalographic recordings revealed that feedback about movement outcomes elicited a feedback error-related negativity: a component of the human event-related brain potential associated with high-level outcome evaluation within medial-frontal cortex. Thus, the data provide evidence that a high-level error-evaluation system within medial-frontal cortex plays a key role in learning to control our body posture.
To maximize reward, we are faced with the dilemma of having to balance the exploration of new res... more To maximize reward, we are faced with the dilemma of having to balance the exploration of new response options and the exploitation of previous choices. Here, we sought to determine if the event-related brain potential (ERP) in the P300 time range is sensitive to decisions to explore or exploit within the context of a sequential risk-taking task. Specifically, the task we used required participants to continually explore their options-whether they should "push their luck" and keep gambling or "take the money and run" and collect their winnings. Our behavioral analysis yielded two distinct distributions of response times: a larger group of short-decision times and a smaller group of long-decision times. Interestingly, these data suggest that participants adopted one of two modes of control on any given trial: a mode where they quickly decided to keep gambling (i.e. exploit), and a mode where they deliberated whether to the take the money they had already won or continue gambling (i.e. explore). Importantly, we found that the amplitude of the ERP in the P300 time range was larger for explorative decisions than for exploitative decisions and, further, was correlated with decision time. Our results are consistent with a recent theoretical account that links changes in ERP amplitude in the P300 time range with phasic activity of the locus coeruleus-norepinephrine system and decisions to engage in exploratory behavior.
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