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Abstract The study of perceptual decision making has made significant progress owing to major contributions from two experimental paradigms: the sequential vibrotactile frequency comparison task for the somatosensory domain requiring working memory, and the random-dot motion task in the visual domain requiring evidence accumulation over time. On the one hand, electrophysiological recordings in nonhuman primates and humans have identified changes in firing rates and power modulations of beta band oscillations with the vibrotactile frequencies held in working memory, as well as with the mental operation required for decision making. On the other hand, firing rates and centro-parietal potentials were found to increase to a fixed level at the time of responding during the random-dot motion task, possibly reflecting an underlying evidence accumulation mechanism until a decision threshold is met. Here, to bridge these two paradigms, we presented two visual random-dot motion stimuli in a sequential comparison task while recording EEG from human volunteers. We identified a modulation of prefrontal beta band power that scaled with the level of dot motion coherence of the first stimulus during a short retention interval. Furthermore, beta power in premotor areas was modulated by participants' choices approximately 700 ms before responses were given via button press. At the same time, dot motion patches of the second stimulus evoked a pattern of broadband centro-parietal signal build-up till responses were made, whose peak varied with trial difficulty. Hence, we show that known modulations of beta power during working memory and decision making extend from the vibrotactile to the visual domain and provide support for the notion of evidence accumulation as an unconfined decision-making mechanism generalizing over distinct decision types. Highlights • Comparing amount of motion between two sequentially presented random dot stimuli. • Prefrontal beta power encodes to-be-remembered amount of motion during retention. • Premotor beta power indexes participants' choices before responding. • Centro-parietal positivity tracks decision, but not evidence for single percepts. • Centro-parietal positivity does not hit a fixed bound when responding. [ABSTRACT FROM AUTHOR]

• NMDA antagonist dizocilpine selectively impaired accuracy on the odor span task. • Drug effects were exacerbated by increases in memory load and distraction. • Both attentional and capacity deficits in schizophrenia are modeled in the task. The rodent odor span task (OST) uses an incrementing non-matching to sample procedure in which a series of odors is presented and selection of the session-novel odor is reinforced. An OST is frequently used to test the effects of neurobiological variables on memory capacity as the number of odors to remember increases during the course of the session. In this regard, one important finding has been that NMDA receptor antagonists selectively impair OST performance at doses that spare accuracy on control tasks. However, in many versions of the odor span task the number of stimuli to remember is confounded with the number of distractor odors presented to the rat on each trial. The present study compared the effects of the NMDA antagonist dizocilpine when the number of choices was held constant at two (one novel odor—S+ and one previously presented distractor odor—S−) and when the number of choice stimuli was permitted to increase up to 10 (one S+ and 9 S−). Dizocilpine impaired OST accuracy at doses that had no effect on a reference memory control task in both 2-choice and 10-choice conditions; however, the dose-response function was shifted to the left in the 10-choice tests. The impairments produced by dizocilpine were exacerbated as the memory load increased in both 2- and 10-choice conditions. These findings support the hypothesis that NMDA antagonism reduces the number of stimuli that rats can remember accurately, but the interaction between the effective DZP dose and the number of distractors shows that drug effects on OST performances may involve attentional factors in addition to memory capacity. The findings also demonstrate that variations in number of OST distractors can be used to alter sensitivity of the task. [ABSTRACT FROM AUTHOR]

• Number of thought probes may effect measurement of mind wandering during a task. • Number of thought probes differentially effect mind wandering based on task demands. • More thought probes result in more mind wandering during a working memory task. • More thought probes result in less mind wandering during a video lecture. • Thought probes interact with attentional control demands, influence mind wandering. Mind wandering is a topic of great interest in many areas, but as with all psychological constructs, the interpretation of experimental results might depend on the way it is measured. A common way of measuring mind wandering in experiments is with self-report thought probes. An important question with this methodology is if the probe itself may be influencing participants' mind wandering. Previous research suggests that multiple thought probes throughout a task may lead to less mind wandering. However, in some studies (e.g., Schubert et al, 2019) the probes occurred during a recorded lecture video and in the others (e.g., Seli et al, 2016) the probes occurred during a sustained attention to response task (SART). What is missing in the current literature is a comparison of the effect the number of thought probes has on mind wandering during a task that requires a greater deal of thought control throughout the task to perform well, such as a complex span task or working memory. As such, in the two experiments presented here we randomly assigned participants to one of four conditions. Conditions contained a minimum of one and a maximum of six probes. In the first experiment, we found that participants who had received fewer probes mind wandered less during an operation span task, supporting our hypothesis. In the second experiment, we found that participants who had received fewer probes mind wandered more during a video lecture. The results suggest that thought probes interact with attentional control demands to influence mind wandering. [ABSTRACT FROM AUTHOR]

Every day millions of women worldwide take oral contraceptives (OCs). Findings of their impact on cognition are inconclusive. It is suggested that OC generation may act as a potential modulating factor driving the inconsistencies among existing studies. The current study investigated whether the androgenic activity of monophasic OCs affects working memory (WM). We compared women using androgenic second generation OCs (OC 2) and anti-androgenic fourth generation OCs (OC 4) in addition to naturally cycling women (NC). Participants performed a visuospatial and verbal WM task. In the visuospatial WM task, participants decided whether an abstract pattern was symmetrical or not, while simultaneously maintaining a sequence of spatial positions of a square appearing in a matrix. In the verbal WM task, participants solved simple arithmetic equations while simultaneously maintaining a sequence of letters. Our results showed that NC women and OC users (OC 2+4) did not differ on central measures in either WM task. However, when the OC generation was considered, OC 2 users were significantly faster in the symmetry decision subtask of the visuospatial WM task compared to OC 4 and NC women. This effect was thereby independent of the ethinylestradiol level in OC users. No differences between groups were found in the various measures of the verbal WM task. Our findings add further evidence that OCs androgenicity impacts selective visuospatial processes. • the impact of oral contraceptives' (OC) androgenicity on working memory (WM) was tested. • androgenic OC 2 users, antiandrogenic OC 4 user, and naturally cycling women were compared. • women performed a visuospatial and verbal WM task. • symmetry processing speed was selectively increased in OC 2 users. • our findings indicate that OC generation affects isolated visuospatial abilities. [ABSTRACT FROM AUTHOR]

[Display omitted] • Sixteen male participants were enrolled in a randomized crossover control study involving three sleep-deprivation sessions. • The study investigated the effect of modafinil on working memory decline caused by sleep deprivation, by studying ERPs. • Modafinil may effectively improve the decline in pronunciation-related working memory after sleep deprivation. We aimed to explore whether modafinil mitigates the working memory decline induced by 36 h of acute total sleep deprivation (36-h TSD). Sixteen healthy male participants were enrolled in a randomized double-blind crossover control study involving three sleep-deprivation sessions. Participants were administered 400 mg of placebo, caffeine, or modafinil during these sessions. Behavior and EEG data were recorded while participants performed pronunciation-related working memory tasks. Behavioral indicators showed that, compared with placebo, modafinil improved the accuracy of pronunciation-related working memory tasks and reduced the response time. Compared with before sleep deprivation, the amplitudes of the event-related potentials (ERPs) increased in the N2 component and decreased in the P3 component after sleep deprivation in the placebo condition. In the caffeine condition, the amplitude of the P3 component decreased, the latency of the N2 component was prolonged, and the N2 amplitude remained unchanged. In the modafinil condition, the P3 latency was shortened, and no significant difference was found in the amplitude of the N2 or P3 ERPs; no significant difference was recorded in the N2 latency. Modafinil (400 mg) effectively ameliorated the decline in pronunciation-related working memory after 36-h TSD, suggesting that it may effectively counteract cognitive decline caused by acute sleep deprivation. [ABSTRACT FROM AUTHOR]

Reward and motivation have positive influences on cognitive-control processes in numerous settings. Models of reward implicate corticostriatal loops and the dopamine (DA) system, with special emphasis on D2 receptors in nucleus accumbens (NAcc). In this study, 11 right-handed males (35-40 years) were scanned with positron emission tomography (PET) in a single [11C]raclopride dynamic scan during rewarded and non-rewarded task switching. Rewarded task switching (relative to baseline task switching) decreased [11C]raclopride binding in NAcc. Decreasing NAcc [11C]raclopride binding was strongly associated with task reaction time measures that reflect individual differences in effort and control strategies. Voxelwise analyses additionally revealed reward-related DA release in anterodorsal caudate, a region previously associated with task-switching. These PET findings provide evidence for striatal DA release during motivated cognitive control, and further suggest that NAcc DA release predicts the task reaction time benefits of reward incentives. [ABSTRACT FROM AUTHOR]

Our perception of time varies with the degree of cognitive engagement in tasks. The perceived passage of time accelerates while working on demanding tasks, whereas time appears to drag during boring situations. Our experiment aimed at investigating whether this relationship is mutual: Can manipulated announcements of elapsed time systematically affect the attentional resources applied to a cognitive task? We measured behavioral performance and the EEG in a whole report working memory paradigm with six items of different colors that each had to be reported after a short delay period. The 32 participants were informed about the current time after each 20 trials, while the clock was running at either 100% (normal), 120% (fast), or 80% (slow) of normal clock speed depending on the experimental block. The mean number of correctly reported colors per trial was significantly increased in the fast as compared to the slow and normal clock conditions. In the EEG, we focused on neural oscillations during working memory encoding and storage. As an electrophysiological correlate of task engagement, frontal theta power during the storage interval was increased in the fast clock condition. Also, the power of frontal theta oscillations predicted the number of correctly reported colors on a single-trial basis. This shows that a covert manipulation of clock speed can lead to an improvement in cognitive performance, presumably mediated by a higher allocation of attentional resources resulting from an adaptation of the subjective passage of time during an experiment. [ABSTRACT FROM AUTHOR]

Freely-moving rodents can solve short-term memory (STM) tasks using "response bridging" strategies, relying on motor patterns instead of mnemonic functions. This limits the interpretational power of results yielded by some STM tasks in rodents. To determine whether head-fixed monkeys can employ parallel non-mnemonic strategies, we measured eye position and velocity of two head-fixed monkeys performing a delayed response reaching and grasping task. We found that eye position during the delay period was correlated with reach direction. Moreover, reach direction as well as grasp object could be predicted from eye kinematics during the delay. Both eye velocity and eye position contributed to the prediction of reach direction. These results show that motor signals carry sufficient information to allow monkeys to solve STM tasks without using any mnemonic functions. Thus, the potential of animals to solve STM tasks using motor patterns is more diverse than previously recognized. [ABSTRACT FROM AUTHOR]

• Effort and discomfort differ between sustained attention and working memory tasks. • Anticipated cognitive effort is greater on a working memory task. • Real-time and remembered cognitive effort are greater on a sustained attention task. • Discomfort is consistently greater on a sustained attention task. • Forecasting error biases may account for changes in subjective effort and discomfort. This study examined individuals' ability to accurately anticipate how cognitively effortful and uncomfortable a task will feel based on a short sample of the task. Participants completed a sustained attention or working memory task. Post-practice, participants rated the effort and discomfort that they anticipated their task would require and engender, respectively. Participants also rated their effort and discomfort during task-administration and the effort and discomfort they recalled feeling after task-administration. Sustained attention task participants anticipated significantly less effort than working memory task participants. Sustained attention task participants felt significantly more effort during the task and remembered feeling more effort than they had anticipated. Working memory task participants felt significantly less effort during the task than they had anticipated. Sustained attention task participants anticipated, experienced, and recalled feeling more discomfort than working memory task participants. Individuals' anticipation of effort required depends on the task and is different from the effort they actually feel during the task and later recall feeling. [ABSTRACT FROM AUTHOR]