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Eric Granholm - One of the best experts on this subject based on the ideXlab platform.

  • sleep deprivation and compensatory Cognitive Effort on a visual information processing task
    Sleep, 2021
    Co-Authors: Molly J Sullan, Sean P A Drummond, Eric Granholm
    Abstract:

    Study objectives Total sleep deprivation (TSD) is often associated with worse performance on tasks of attention and working memory, but some studies show no performance changes. One possibility is that greater compensatory Cognitive Effort is put forth to achieve similar results after TSD. We aimed to better understand the relationship between TSD, Cognitive engagement, and performance outcomes following TSD. Methods Twenty healthy adults completed Cognitive testing following a night of normal sleep and again after ~55 hours of TSD. Participants detected target letters in low (3-item) and high (10-item) load visual letter displays on the span of apprehension task with concurrent pupillometry, a measure of Cognitive Effort. Results We found significantly poorer detection accuracy and marginally longer response times following TSD across both arrays. In both arrays, significantly greater preparatory pupillary responses were found just prior to array onset. There was also a significant session by array interaction for pupillary responses, such that significantly greater dilation was found for the 3-letter array after TSD, while a nonsignificant decline in dilation was found following the 10-letter array after TSD. Conclusions These results suggest a complex relationship between attentional control and Cognitive resource allocation following TSD. Sleep-deprived individuals may allocate more compensatory Cognitive Effort to easier tasks but choose to disengage from more challenging Cognitive tasks that have little perceived reward or probability of success to preserve diminishing Cognitive resources. More work is needed to better delineate the underlying neurological systems involved in these processing load-dependent attentional control mechanisms after TSD.

  • sleep deprivation and compensatory Cognitive Effort on a visual information processing task
    Sleep, 2020
    Co-Authors: Molly J Sullan, Sean P A Drummond, Eric Granholm
    Abstract:

    STUDY OBJECTIVES Total sleep deprivation (TSD) is often associated with worse performance on tasks of attention and working memory, but some studies show no performance changes. One possibility is that greater compensatory Cognitive Effort is put forth to achieve similar results after TSD. We aimed to better understand the relationship between TSD, Cognitive engagement, and performance outcomes following TSD. METHODS 20 healthy adults completed Cognitive testing following a night of normal sleep and again after ~55 hours of TSD. Participants detected target letters in low (3-item) and high (10-item) load visual letter displays on the span of apprehension task with concurrent pupillometry, a measure of Cognitive Effort. RESULTS We found significantly poorer detection accuracy and marginally longer response times following TSD across both arrays. In both arrays, significantly greater preparatory pupillary responses were found just prior to array onset. There was also a significant session by array interaction for pupillary responses, such that significantly greater dilation was found for the 3-letter array after TSD, while a nonsignificant decline in dilation was found following the 10-letter array after TSD. CONCLUSIONS These results suggest a complex relationship between attentional control and Cognitive resource allocation following TSD. Sleep deprived individuals may allocate more compensatory Cognitive Effort to easier tasks but choose to disengage from more challenging Cognitive tasks that have little perceived reward or probability of success to preserve diminishing Cognitive resources. More work is needed to better delineate the underlying neurological systems involved in these processing load-dependent attentional control mechanisms after TSD.

Andrew Westbrook - One of the best experts on this subject based on the ideXlab platform.

  • dopamine promotes Cognitive Effort by biasing the benefits versus costs of Cognitive work
    Science, 2020
    Co-Authors: Andrew Westbrook, R Van Den Bosch, Jessica I Maatta, Lieke Hofmans, Danae Papadopetraki, Roshan Cools, Michael J Frank
    Abstract:

    Stimulants such as methylphenidate are increasingly used for Cognitive enhancement but precise mechanisms are unknown. We found that methylphenidate boosts willingness to expend Cognitive Effort by altering the benefit-to-cost ratio of Cognitive work. Willingness to expend Effort was greater for participants with higher striatal dopamine synthesis capacity, whereas methylphenidate and sulpiride, a selective D2 receptor antagonist, increased Cognitive motivation more for participants with lower synthesis capacity. A sequential sampling model informed by momentary gaze revealed that decisions to expend Effort are related to amplification of benefit-versus-cost information attended early in the decision process, whereas the effect of benefits is strengthened with higher synthesis capacity and by methylphenidate. These findings demonstrate that methylphenidate boosts the perceived benefits versus costs of Cognitive Effort by modulating striatal dopamine signaling.

  • dopamine promotes Cognitive Effort by biasing the benefits versus costs of Cognitive work
    bioRxiv, 2019
    Co-Authors: Andrew Westbrook, R Van Den Bosch, Jessica I Maatta, Lieke Hofmans, Danae Papadopetraki, Roshan Cools, Michael J Frank
    Abstract:

    Stimulants like methylphenidate are increasingly used for Cognitive enhancement, but precise mechanisms are unknown. We found that methylphenidate boosts willingness to expend Cognitive Effort by altering the benefit-to-cost ratio of Cognitive work. Willingness to expend Effort was greater for participants with higher striatal dopamine synthesis capacity, while methylphenidate and sulpiride – a selective D2 receptor antagonist – increased Cognitive motivation more for participants with lower synthesis capacity. A sequential sampling model informed by momentary gaze revealed that decisions to expend Effort are related to amplification of benefit-versus-cost information attended early in the decision process, while the effect of benefits is strengthened with higher synthesis capacity and by methylphenidate. These findings demonstrate that methylphenidate boosts the perceived benefits-versus-costs of Cognitive Effort by modulating striatal dopamine signaling. One Sentence Summary Striatal dopamine increases Cognitive Effort by respectively amplifying and attenuating the subjective benefits and costs of Cognitive control.

  • the subjective value of Cognitive Effort is encoded by a domain general valuation network
    The Journal of Neuroscience, 2019
    Co-Authors: Andrew Westbrook, Bidhan Lamichhane, Todd S Braver
    Abstract:

    Cognitive control is necessary for goal-directed behavior, yet people treat Cognitive control demand as a cost, which discounts the value of rewards in a similar manner as other costs, such as delay or risk. It is unclear, however, whether the subjective value (SV) of Cognitive Effort is encoded in the same putatively domain-general brain valuation network implicated in other cost domains, or instead engages a distinct frontoparietal network, as implied by recent studies. Here, we provide rigorous evidence that the valuation network, with core foci in the ventromedial prefrontal cortex and ventral striatum, also encodes SV during Cognitive Effort-based decision-making in healthy, male and female adult humans. We doubly dissociate this network from frontoparietal regions that are instead recruited as a function of decision difficulty. We show that the domain-general valuation network jointly and independently encodes both reward benefits and Cognitive Effort costs. We also demonstrate that Cognitive Effort SV signals predict choice and are influenced by state and trait motivation, including sensitivity to reward and anticipated task performance. These findings unify Cognitive Effort with other cost domains, and suggest candidate neural mechanisms underlying state and trait variation in willingness to expend Cognitive Effort. SIGNIFICANCE STATEMENT Subjective Effort costs are increasingly understood to diminish Cognitive control over task performance and can thus undermine functioning across health and disease. Yet, we are only beginning to understand how decisions about Cognitive Effort are made. A key question is how subjective values are computed. Recent work suggests that the value of Cognitive Effort might be computed by networks that are distinct from those involved in other domains like intertemporal and risky decision-making, implying distinct mechanisms. Here we demonstrate that the domain-general network also encodes Effort-discounted value, linking Cognitive Effort closely with other domains. Our results thus elucidate key mechanisms supporting decisions about Cognitive Effort, and point to candidate neural targets for intervention in disorders involving impaired Cognitive motivation.

  • the subjective value of Cognitive Effort is encoded by a domain general valuation network
    bioRxiv, 2018
    Co-Authors: Andrew Westbrook, Bidhan Lamichhane, Todd S Braver
    Abstract:

    Summary Cognitive control is necessary for goal-directed behavior, yet people treat control as costly, discounting goal value by Cognitive demands in a similar manner as they would for delayed or risky outcomes. It is unclear, however, whether a putatively domain-general valuation network implicated in other cost domains also encodes the subjective value (SV) of Cognitive Effort. Here, we demonstrate that a valuation network, centered on the ventromedial prefrontal cortex and ventral striatum, also encodes SV during Cognitive Effort-based decision-making. We doubly dissociate this network from a primarily frontoparietal network recruited as a function of decision difficulty. We also find evidence that SV signals predict choice and are influenced by state and trait motivation, including sensitivity to reward and anticipated task performance. These findings unify Cognitive Effort with other cost domains, and inform physiological mechanisms of SV representations underlying the willingness to expend Cognitive Effort.

  • negative symptoms are associated with an increased subjective cost of Cognitive Effort
    Journal of Abnormal Psychology, 2016
    Co-Authors: Adam J Culbreth, Andrew Westbrook
    Abstract:

    Motivational deficits in schizophrenia are proposed to be attributable in part to abnormal Effort-cost computations. Inflated subjective Cognitive Effort costs may explain diminished functioning in schizophrenia to the extent that they drive avoidance of complex decision-making and planning. Although previous data support inflated subjective physical Effort costs for individuals with schizophrenia, evidence on Cognitive Effort is mixed. We exploited the methodological advantages of a recently developed Cognitive Effort-discounting paradigm (Westbrook, Kester, & Braver, 2013) to examine Effort-cost computations in schizophrenia. The paradigm quantifies subjective costs in terms of explicit, continuous discounting of monetary rewards based on parametrically varied demands (levels N of the N-back working memory task), holding objective features of task duration and reward likelihood constant. Both healthy participants (N = 25) and schizophrenia patients (N = 25) showed systematic influences of reward and task demands on choice patterns. Critically, however, participants with schizophrenia discounted rewards more steeply as a function of Effort, indicating that Effort was more costly for this group. Moreover, discounting varied robustly with symptomatology, such that schizophrenia patients with greater clinically rated negative symptom severity discounted rewards more steeply. These findings extend the current literature on abnormal-Effort cost computations in schizophrenia by establishing a clear relationship between the costliness of Cognitive Effort and negative symptoms. (PsycINFO Database Record

Catharine A Winstanley - One of the best experts on this subject based on the ideXlab platform.

  • evaluation of Cognitive Effort in rats is not critically dependent on ventrolateral orbitofrontal cortex
    European Journal of Neuroscience, 2021
    Co-Authors: Mason M Silveira, Sebastian N Wittekindt, Sophie A Ebsary, Catharine A Winstanley
    Abstract:

    Organisms must frequently evaluate the amount of Effort to invest in pursuing future rewards. Despite explicit awareness of the potential benefits of Cognitive work, individuals vary in their willingness to attempt Cognitively demanding tasks, regardless of intellectual ability. Such differences may suggest that the degree to which Cognitive Effort degrades perceived outcome value is a subjective, rather than objective, process, similar to risk and delay discounting. Although numerous studies suggest the orbitofrontal cortex (OFC) is important for allowing subjective value estimates to be updated and/or used in cost/benefit decision-making, the causal role of the OFC in valuations of mental Effort has received scant investigation. We therefore trained 24 female Long-Evans rats on the rodent Cognitive Effort task (rCET) and assessed performance following temporary bilateral inactivation of the ventrolateral OFC (vlOFC). In the rCET, rats decide at trial outset whether to perform an easy or hard attentional challenge, namely to localize a brief visual stimulus to one of five possible locations. The difficulty of the challenge is determined by the stimulus duration (1.0 vs. 0.2s for easy vs. hard trials respectively), and success on hard trials results in double the sugar pellet rewards. Somewhat surprisingly, inactivations of the vlOFC did not affect rats' willingness or ability to exert Cognitive Effort for larger rewards, despite increasing omissions and motor impulsivity on-task. When considered with previous work, it appears the vlOFC plays a minimal role in Cognitive Effort allocation specifically, and in valuations of Effort more generally.

  • investigating serotonergic contributions to Cognitive Effort allocation attention and impulsive action in female rats
    Journal of Psychopharmacology, 2020
    Co-Authors: Mason M Silveira, Sebastian N Wittekindt, Leili Mortazavi, Brett A Hathaway, Catharine A Winstanley
    Abstract:

    Background:Individuals must frequently evaluate whether it is worth allocating Cognitive Effort for desired outcomes. Motivational deficits are a common feature of psychiatric illness such as major...

  • dissociable contributions of dorsal and ventral striatal regions on a rodent cost benefit decision making task requiring Cognitive Effort
    Neuropharmacology, 2018
    Co-Authors: Mason M Silveira, Melanie Tremblay, Catharine A Winstanley
    Abstract:

    Cognitive Effort is a ubiquitous process, yet surprisingly little is known about the brain mechanisms responsible for evaluating it. Here, we utilize the rat Cognitive Effort Task (rCET) to probe the striatum's role in deciding between options that vary in the amount of Cognitive Effort required for success. In the rCET, animals choose to perform either an easy trial, in which the attentional demand is low but the potential reward is small, or a difficult trial which is more attentionally demanding but can yield twice the sugar pellets. Twenty-six male Long Evans rats were trained on the rCET and the effects of pharmacologically inactivating the dorsomedial striatum (DMS) and core region of the nucleus accumbens were determined. Temporary inactivation of the DMS decreased all animals' choice of the high-Effort, high-reward option, impaired attentional accuracy, and robustly increased premature responding without impairing general indices of motor ability. The DMS therefore appears necessary for the integration of Cognitive signals required for optimal performance. In stark contrast, following temporary inactivation of the ventral striatum, subjects were fundamentally unable to perform the task, as reflected by a drastic decrease in the number of trials initiated and an increase in omitted responses. Together, these data suggest the striatum is likely part of a larger cortico-limbic-striatal network whose function is to optimize decisions requiring Cognitive Effort costs, at least in the attentional domain, and that striatal subregions have dissociable roles in the adjudication and application of this form of Cognitive Effort.

  • δ9 tetrahydrocannabinol decreases willingness to exert Cognitive Effort in male rats
    Journal of Psychiatry & Neuroscience, 2017
    Co-Authors: Mason M Silveira, Wendy K Adams, Maria Morena, Matthew N Hill, Catharine A Winstanley
    Abstract:

    BACKGROUND Acceptance of cannabis use is growing. However, prolonged use is associated with diminished psychosocial outcomes, potentially mediated by drug-induced Cognitive impairments. Δ9-Tetrahydrocannabinol (THC) is the main psychoactive ingredient in cannabis, yet other phytocannabinoids in the plant, such as cannabidiol (CBD), have unique properties. Given that CBD can modulate the undesirable effects of THC, therapeutic agents, such as nabiximols, contain higher CBD:THC ratios than illicit marijuana. We tested the hypothesis that THC impairs a relevant Cognitive function for long-term success, namely willingness to exert Cognitive Effort for greater rewards, and that CBD could attenuate such decision-making impairments. METHODS Male Long-Evans rats (n = 29) performing the rat Cognitive Effort task (rCET) received acute THC and CBD, independently and concurrently, in addition to other cannabinoids. Rats chose between 2 options differing in reward magnitude, but also in the Cognitive Effort (attentional load) required to obtain them. RESULTS We found that THC decreased choice of hard trials without impairing the animals' ability to accurately complete them. Strikingly, this impairment was correlated with CB1 receptor density in the medial prefrontal cortex - an area previously implicated in Effortful decision-making. In contrast, CBD did not affect choice. Coadministration of 1:1 CBD:THC matching that in nabiximols modestly attenuated the deleterious effects of THC in "slacker" rats. LIMITATIONS Only male rats were investigated, and the THC/CBD coadministration experiment was carried out in a subset of individuals. CONCLUSION These findings confirm that THC, but not CBD, selectively impairs decision-making involving Cognitive Effort costs. However, coadministration of CBD only partially ameliorates such THC-induced dysfunction.

  • prefrontal cortical inactivations decrease willingness to expend Cognitive Effort on a rodent cost benefit decision making task
    Cerebral Cortex, 2016
    Co-Authors: Jay G Hosking, Paul J Cocker, Catharine A Winstanley
    Abstract:

    Personal success often necessitates expending greater Effort for greater reward but, equally important, also requires judicious use of our limited Cognitive resources (e.g., attention). Previous animal models have shown that the prelimbic (PL) and infralimbic (IL) regions of the prefrontal cortex (PFC) are not involved in (physical) Effort-based choice, whereas human studies have demonstrated PFC contributions to (mental) Effort. Here, we utilize the rat Cognitive Effort Task (rCET) to probe PFC's role in Effort-based decision making. In the rCET, animals can choose either an easy trial, where the attentional demand is low but the reward (sugar) is small or a difficult trial on which both the attentional demand and reward are greater. Temporary inactivation of PL and IL decreased all animals' willingness to expend mental Effort and increased animals' distractibility; PL inactivations more substantially affected performance (i.e., attention), whereas IL inactivations increased motor impulsivity. These data imply that the PFC contributes to attentional resources, and when these resources are diminished, animals shift their choice (via other brain regions) accordingly. Thus, one novel therapeutic approach to deficits in Effort expenditure may be to focus on the resources that such decision making requires, rather than the decision-making process per se.

Molly J Sullan - One of the best experts on this subject based on the ideXlab platform.

  • sleep deprivation and compensatory Cognitive Effort on a visual information processing task
    Sleep, 2021
    Co-Authors: Molly J Sullan, Sean P A Drummond, Eric Granholm
    Abstract:

    Study objectives Total sleep deprivation (TSD) is often associated with worse performance on tasks of attention and working memory, but some studies show no performance changes. One possibility is that greater compensatory Cognitive Effort is put forth to achieve similar results after TSD. We aimed to better understand the relationship between TSD, Cognitive engagement, and performance outcomes following TSD. Methods Twenty healthy adults completed Cognitive testing following a night of normal sleep and again after ~55 hours of TSD. Participants detected target letters in low (3-item) and high (10-item) load visual letter displays on the span of apprehension task with concurrent pupillometry, a measure of Cognitive Effort. Results We found significantly poorer detection accuracy and marginally longer response times following TSD across both arrays. In both arrays, significantly greater preparatory pupillary responses were found just prior to array onset. There was also a significant session by array interaction for pupillary responses, such that significantly greater dilation was found for the 3-letter array after TSD, while a nonsignificant decline in dilation was found following the 10-letter array after TSD. Conclusions These results suggest a complex relationship between attentional control and Cognitive resource allocation following TSD. Sleep-deprived individuals may allocate more compensatory Cognitive Effort to easier tasks but choose to disengage from more challenging Cognitive tasks that have little perceived reward or probability of success to preserve diminishing Cognitive resources. More work is needed to better delineate the underlying neurological systems involved in these processing load-dependent attentional control mechanisms after TSD.

  • sleep deprivation and compensatory Cognitive Effort on a visual information processing task
    Sleep, 2020
    Co-Authors: Molly J Sullan, Sean P A Drummond, Eric Granholm
    Abstract:

    STUDY OBJECTIVES Total sleep deprivation (TSD) is often associated with worse performance on tasks of attention and working memory, but some studies show no performance changes. One possibility is that greater compensatory Cognitive Effort is put forth to achieve similar results after TSD. We aimed to better understand the relationship between TSD, Cognitive engagement, and performance outcomes following TSD. METHODS 20 healthy adults completed Cognitive testing following a night of normal sleep and again after ~55 hours of TSD. Participants detected target letters in low (3-item) and high (10-item) load visual letter displays on the span of apprehension task with concurrent pupillometry, a measure of Cognitive Effort. RESULTS We found significantly poorer detection accuracy and marginally longer response times following TSD across both arrays. In both arrays, significantly greater preparatory pupillary responses were found just prior to array onset. There was also a significant session by array interaction for pupillary responses, such that significantly greater dilation was found for the 3-letter array after TSD, while a nonsignificant decline in dilation was found following the 10-letter array after TSD. CONCLUSIONS These results suggest a complex relationship between attentional control and Cognitive resource allocation following TSD. Sleep deprived individuals may allocate more compensatory Cognitive Effort to easier tasks but choose to disengage from more challenging Cognitive tasks that have little perceived reward or probability of success to preserve diminishing Cognitive resources. More work is needed to better delineate the underlying neurological systems involved in these processing load-dependent attentional control mechanisms after TSD.

Todd S Braver - One of the best experts on this subject based on the ideXlab platform.

  • the subjective value of Cognitive Effort is encoded by a domain general valuation network
    The Journal of Neuroscience, 2019
    Co-Authors: Andrew Westbrook, Bidhan Lamichhane, Todd S Braver
    Abstract:

    Cognitive control is necessary for goal-directed behavior, yet people treat Cognitive control demand as a cost, which discounts the value of rewards in a similar manner as other costs, such as delay or risk. It is unclear, however, whether the subjective value (SV) of Cognitive Effort is encoded in the same putatively domain-general brain valuation network implicated in other cost domains, or instead engages a distinct frontoparietal network, as implied by recent studies. Here, we provide rigorous evidence that the valuation network, with core foci in the ventromedial prefrontal cortex and ventral striatum, also encodes SV during Cognitive Effort-based decision-making in healthy, male and female adult humans. We doubly dissociate this network from frontoparietal regions that are instead recruited as a function of decision difficulty. We show that the domain-general valuation network jointly and independently encodes both reward benefits and Cognitive Effort costs. We also demonstrate that Cognitive Effort SV signals predict choice and are influenced by state and trait motivation, including sensitivity to reward and anticipated task performance. These findings unify Cognitive Effort with other cost domains, and suggest candidate neural mechanisms underlying state and trait variation in willingness to expend Cognitive Effort. SIGNIFICANCE STATEMENT Subjective Effort costs are increasingly understood to diminish Cognitive control over task performance and can thus undermine functioning across health and disease. Yet, we are only beginning to understand how decisions about Cognitive Effort are made. A key question is how subjective values are computed. Recent work suggests that the value of Cognitive Effort might be computed by networks that are distinct from those involved in other domains like intertemporal and risky decision-making, implying distinct mechanisms. Here we demonstrate that the domain-general network also encodes Effort-discounted value, linking Cognitive Effort closely with other domains. Our results thus elucidate key mechanisms supporting decisions about Cognitive Effort, and point to candidate neural targets for intervention in disorders involving impaired Cognitive motivation.

  • the subjective value of Cognitive Effort is encoded by a domain general valuation network
    bioRxiv, 2018
    Co-Authors: Andrew Westbrook, Bidhan Lamichhane, Todd S Braver
    Abstract:

    Summary Cognitive control is necessary for goal-directed behavior, yet people treat control as costly, discounting goal value by Cognitive demands in a similar manner as they would for delayed or risky outcomes. It is unclear, however, whether a putatively domain-general valuation network implicated in other cost domains also encodes the subjective value (SV) of Cognitive Effort. Here, we demonstrate that a valuation network, centered on the ventromedial prefrontal cortex and ventral striatum, also encodes SV during Cognitive Effort-based decision-making. We doubly dissociate this network from a primarily frontoparietal network recruited as a function of decision difficulty. We also find evidence that SV signals predict choice and are influenced by state and trait motivation, including sensitivity to reward and anticipated task performance. These findings unify Cognitive Effort with other cost domains, and inform physiological mechanisms of SV representations underlying the willingness to expend Cognitive Effort.

  • dopamine does double duty in motivating Cognitive Effort
    Neuron, 2016
    Co-Authors: Andrew Westbrook, Todd S Braver
    Abstract:

    Cognitive control is subjectively costly, suggesting that engagement is modulated in relationship to incentive state. Dopamine appears to play key roles. In particular, dopamine may mediate Cognitive Effort by two broad classes of functions: (1) modulating the functional parameters of working memory circuits subserving Effortful cognition, and (2) mediating value-learning and decision-making about Effortful Cognitive action. Here, we tie together these two lines of research, proposing how dopamine serves "double duty", translating incentive information into Cognitive motivation.

  • what is the subjective cost of Cognitive Effort load trait and aging effects revealed by economic preference
    PLOS ONE, 2013
    Co-Authors: Andrew Westbrook, Daria Kester, Todd S Braver
    Abstract:

    It has long been assumed that people treat Cognitive Effort as costly, but also that such Effort costs may vary greatly across individuals. Individual differences in subjective Effort could present a major and pervasive confound in behavioral and neuroscience assessments, by conflating Cognitive ability with Cognitive motivation. Self-report Cognitive Effort scales have been developed, but objective measures are lacking. In this study, we use the behavioral economic approach of revealed preferences to quantify subjective Effort. Specifically, we adapted a well-established discounting paradigm to measure the extent to which Cognitive Effort causes participants to discount monetary rewards. The resulting metrics are sensitive to both within-individual factors, including objective load and reward amount, and between-individual factors, including age and trait Cognitive engagement. We further validate Cognitive Effort discounting by benchmarking it against well-established measures of delay discounting. The results highlight the promise and utility of behavioral economic tools for assessing trait and state influences on Cognitive motivation.