Simple Cognitive Tasks Research Articles

Process in Evaluation Index of Intellectual Productivity Based on Work Concentration

 Abstract—The authors have proposed a concentration time ratio (CTR) as a new evaluation index of intellectual productivity, which had been difficult to be quantitatively evaluated, with a concept of concentration on intellectual work. When quantitatively evaluating intellectual productivity with simple cognitive task method, the result is often affected by learning effect. In order to evaluate how office environment affects the CTR when an office environment is changed, a subject experiment was conducted in which the illumination condition of the room was changed. As the result, the performances of cognitive tasks were affected by the learning effect, however it was found that the index was affected not by the learning effect but by changing the illumination conditions.

3-Sweep

We introduce an interactive technique for manipulating simple 3D shapes based on extracting them from a single photograph. Such extraction requires understanding of the components of the shape, their projections, and relations. These simple cognitive tasks for humans are particularly difficult for automatic algorithms. Thus, our approach combines the cognitive abilities of humans with the computational accuracy of the machine to solve this problem. Our technique provides the user the means to quickly create editable 3D parts---human assistance implicitly segments a complex object into its components, and positions them in space. In our interface, three strokes are used to generate a 3D component that snaps to the shape's outline in the photograph, where each stroke defines one dimension of the component. The computer reshapes the component to fit the image of the object in the photograph as well as to satisfy various inferred geometric constraints imposed by its global 3D structure. We show that with this intelligent interactive modeling tool, the daunting task of object extraction is made simple. Once the 3D object has been extracted, it can be quickly edited and placed back into photos or 3D scenes, permitting object-driven photo editing tasks which are impossible to perform in image-space. We show several examples and present a user study illustrating the usefulness of our technique.

Change in brain neural activation during stress due to a continued simple cognitive task

Change in brain neural activation during stress due to a continued simple cognitive task

Warmth of familiarity and chill of error: Affective consequences of recognition decisions

The present research aimed to assess the effect of recognition decision on subsequent affective evaluations of recognised and non-recognised objects. Consistent with the proposed account of post-decisional preferences, results showed that the effect of recognition on preferences depends upon objective familiarity. If stimuli are recognised, liking ratings are positively associated with exposure frequency; if stimuli are not recognised, this link is either absent (Experiment 1) or negative (Experiments 2 and 3). This interaction between familiarity and recognition exists even when recognition accuracy is at chance level and the “mere exposure” effect is absent. Finally, data obtained from repeated measurements of preferences and using manipulations of task order confirm that recognition decisions have a causal influence on preferences. The findings suggest that affective evaluation can provide fine-grained access to the efficacy of cognitive processing even in simple cognitive tasks.

The influence of power law distributions on long-range trial dependency of response times

Empirical response time distributions from simple cognitive tasks are typically unimodal and positively skewed. In contrast, variance based scaling analyses, which have been used to study long-range dependency via the Hurst exponent, H>0.5, assume Gaussian response time distributions. This article presents a general method which can identify long-range trial dependency for response time series with power law distributions. The method fits an α-stable distribution to the response time series which satisfies a general version of the central limit theorem and consequently, an α-stable extension (Hq=0>1/α) of long-range dependency. The method was used to reanalyze 96 response time series from three existing data sets which included simple reaction time, word naming, choice decision, and interval estimation tasks. The results showed that all response time distributions were appropriately modelled by an α-stable distribution. Furthermore, the response time series from the simple response and word naming tasks were not long-range dependent when the α-stable definition Hq=0>1/α was used in place of the Gaussian response time distribution definition Hq=2>0.5. The deviation between the two definitions of long-range dependency was shown to be caused by divergence of the variance for response time distributions with power-law decaying tails. The study concludes that the new α-stable definition, Hq=0>1/α, of the long-range trial dependency should be used in the research of response time series instead of the Gaussian definition, Hq=2>0.5.

On the time course of synchronization patterns of neuronal discharges in the human brain during cognitive tasks.

Using intracerebral EEG recordings in a large cohort of human subjects, we investigate the time course of neural cross-talk during a simple cognitive task. Our results show that human brain dynamics undergo a characteristic sequence of synchronization patterns across different frequency bands following a visual oddball stimulus. In particular, an initial global reorganization in the delta and theta bands (2–8 Hz) is followed by gamma (20–95 Hz) and then beta band (12–20 Hz) synchrony.

Updates and Evidence Concerning Concussion in the Physically Active Population

Updates and Evidence Concerning Concussion in the Physically Active Population

Socially triggered negative affect impairs performance in simple cognitive tasks

The aim of this research was to investigate the influence of a social-evaluative context on simple cognitive tasks. While another person present in the room evaluated photographs of beautiful women or landscapes by beauty/attractiveness, female participants had to perform a combination of digit-categorization and spatial-compatibility task. There, before every trial, one of the women or landscape pictures was presented. Results showed selective performance impairments: the numerical distance effects increased on trials that followed women pictures but only, if another person concurrently evaluated these women pictures. In a second experiment, using the affective priming paradigm, the authors show that female pictures have a more negative connotation when they are concurrently evaluated by another person (social-evaluative context) than when they are not evaluated (neutral context). Together, these results suggest that the social-evaluative context triggers mild negative affective reactions to women pictures which then impair performance in an unrelated task.

Episodic context binding in task switching: Evidence from amnesia

The purpose of the present study was to investigate whether amnesic patients show a bivalency effect. The bivalency effect refers to the performance slowing that occurs when switching tasks and bivalent stimuli appear occasionally among univalent stimuli. According to the episodic context binding account, bivalent stimuli create a conflict-loaded context that is re-activated on subsequent trials and thus it is assumed that it depends on memory binding processes. Given the profound memory deficit in amnesia, we hypothesized that the bivalency effect would be largely reduced in amnesic patients. We tested sixteen severely amnesic patients and a control group with a paradigm requiring predictable alternations between three simple cognitive tasks, with bivalent stimuli occasionally occurring on one of these tasks. The results showed the typical bivalency effect for the control group, that is, a generalized slowing for each task. In contrast, for amnesic patients, only a short-lived slowing was present on the task that followed immediately after a bivalent stimulus, indicating that the binding between tasks and context was impaired in amnesic patients.

A Neurophysicist's view to the evolving brain based on neural physiological measurements; diagnosis, development, and accelerated cognitive processing

We present a novel platform to facilitate the growth of applied quantum information processing for neural circuitry, neural stimulation, and cognitive engineering. Cognitive computation has historically been studied by rich metaphors of language constructs, computational models for information processing, and semantic interpretations. Cortical interactions at the cellular and sub cellular level have been established for various cognitive tasks by behavioral and computational neuroscientists. This has enabled us to explore cognitive circuitry given a mathematical and psychophysical basis for information processing and neural decision making. We invite original works in applied physics, computing, and information theory pertaining to neural choice specifically with the intent of developing non-linear mathematical models and theory for neural computation. Various modalities have emerged for physiological processing of neural signals with the premise of measuring electrical or magnetic activity for cortical source localization for simple cognitive tasks. Primary amongst these are EEG and MEG that measure electrical current and magnetic field strengths relative to ambient environments of signal to noise ratios. We propose to extend the physiological measurement paradigm toward creating computational and physics-based building blocks for neural information processing and cognitive function. The goals are dual, to apply our learning of neural measurements and observations toward a constructional cortical framework and improve on current neural processing model for cognitive enhancement, rehabilitation, and cognitive evolution. Efforts are orchestrated toward mathematically sound arguments and quantum information theoretic frameworks to explain neural information processing and cognitive circuitry. Theories such as the Hebbian rule for learning, “Cells that wire together fire together,” are famous for their considerations in foundational cognitive neuroscience and address simplistic rules for cognitive behavior. We intend to create computational models for learning and neurodevelopment toward explaining complex cognitive decisions and improving cognitive function with emerging brain computing interfaces. We invite quantum simulation models for neural computing toward strides in computational neuroscience. Special preference would be given to strong foundations in mathematical neuroscience for objectifying cognitive function as relates to human brain.

Does Herd Behaviour Arise Easier Under Time Pressure? Experimental Approach

In this paper I explain individual propensity to herding behaviour and its relationship to time-pressure by conducting a laboratory experiment. I let subjects perform a simple cognitive task with the possibility to herd under different levels of time pressure. In the main treatments, subjects had a chance to revise their decision after seeing decisions of others, which I take as an indicator of herding behaviour. The main findings are that the propensity to herd was not significantly influenced by different levels of time pressure, although there could be an indirect effect through other variables, such as the time subjects spent revising the decision. Heart-rate significantly increased over the baseline during the performance of a task and its correlation to the subjectively stated level of stress was positive but very weak, which suggests that time pressure may not automatically induce stress but increase effort instead.

White matter correlates of cognitive domains in normal aging with diffusion tensor imaging

The ability to perform complex as well as simple cognitive tasks engages a network of brain regions that is mediated by the white matter fiber bundles connecting them. Different cognitive tasks employ distinctive white matter fiber bundles. The temporal lobe and its projections subserve a variety of key functions known to deteriorate during aging. In a cohort of 52 healthy subjects (ages 25–82 years), we performed voxel-wise regression analysis correlating performance in higher-order cognitive domains (executive function, information processing speed, and memory) with white matter integrity, as measured by diffusion tensor imaging (DTI) fiber tracking in the temporal lobe projections [uncinate fasciculus (UF), fornix, cingulum, inferior longitudinal fasciculus (ILF), and superior longitudinal fasciculus (SLF)]. The fiber tracts were spatially registered and statistical parametric maps were produced to spatially localize the significant correlations. Results showed that performance in the executive function domain is correlated with DTI parameters in the left SLF and right UF; performance in the information processing speed domain is correlated with fractional anisotropy (FA) in the left cingulum, left fornix, right and left ILF and SLF; and the memory domain shows significant correlations with DTI parameters in the right fornix, right cingulum, left ILF, left SLF and right UF. These findings suggest that DTI tractography enables anatomical definition of region of interest (ROI) for correlation of behavioral parameters with diffusion indices, and functionality can be correlated with white matter integrity.

Neurophysiological pharmacodynamic measures of groups and individuals extended from simple cognitive tasks to more “lifelike” activities

ObjectiveExtend a method to track neurophysiological pharmacodynamics during repetitive cognitive testing to a more complex “lifelike” task. MethodsAlcohol was used as an exemplar psychoactive substance. An equation, derived in an exploratory analysis to detect alcohol’s EEGs effects during repetitive cognitive testing, was validated in a Confirmatory Study on a new group whose EEGs after alcohol and placebo were recorded during working memory testing and while operating an automobile driving simulator. ResultsThe equation recognized alcohol by combining five times beta plus theta power. It worked well (p<.0001) when applied to both tasks in the confirmatory group. The maximum EEG effect occurred 2–2.5h after drinking (>1h after peak BAC) and remained at 90% at 3.5–4h (BAC<50% of peak). Individuals varied in the magnitude and timing of the EEG effect. ConclusionThe equation tracked the EEG response to alcohol in the Confirmatory Study during both repetitive cognitive testing and a more complex “lifelike” task. The EEG metric was more sensitive to alcohol than several autonomic physiological measures, task performance measures or self-reports. SignificanceUsing EEG as a biomarker to track neurophysiological pharmacodynamics during complex “lifelike” activities may prove useful for assessing how drugs affect integrated brain functioning.

Cognitive and affective Theory of Mind in mild to moderate Alzheimer's disease

Theory of Mind (ToM) allows one's own and others' cognitive and emotional mental states to be inferred. Although many patients with Alzheimer's disease (AD) display impaired social functioning as their disease progresses, very few studies have investigated ToM in AD. Those that have done so suggest that patients' ToM deficits are the consequence of other cognitive impairments. The aim of this study was thus to investigate changes in both the cognitive and the affective dimensions of ToM in AD, using tasks designed to circumvent the patients' comprehension difficulties. Sixteen mild to moderate AD patients and 15 healthy controls matched on age, sex and education level underwent cognitive (preference judgment and first- and second-order false belief) and affective (Reading the Mind in the Eyes) ToM assessments. Comprehension of false belief stories was verified and an additional neuropsychological examination was undergone. We observed impaired performances by AD patients on all the ToM tasks. While working memory and executive functioning impairments contributed to the deterioration in the more complex aspects of cognitive ToM abilities as highlighted by a correlation analysis, we failed to observe any comprehension difficulties in patients who performed poorly on simple cognitive ToM tasks, which suggests that AD truly affects cognitive ToM.

Combating Vigilance Decrements in a Sustained Attention Task: Lack of Support for the Utility of a Cognitive Intervention Secondary Task

Results from previous studies (St. John &amp; Risser, 2007, 2009) indicate the addition of a simple cognitive secondary task may mitigate vigilance decrements for a sustained attention task involving target acquisition. The effectiveness of the cognitive task increased when its onset was triggered by physiological indicators of inattention. The current study examined the generalizability of this methodology with a few modifications. A no intervention condition was added to provide a baseline and a short perceptual vigilance task (AVT) was added to examine the construct validity of the experimental task (ET). Finally, instead of using physiological indicators to trigger the intervention, a schedule was used that resembled that of the physiological intervention. Although vigilance decrements were observed for both the AVT and ET, only a weak relationship was observed between the two tasks. ET performance was not affected by the cognitive intervention. The weak relationship between the AVT and ET scores suggests that they are not measuring the same constructs. Further, the failure to replicate previous findings casts doubts on the robustness of the cognitive intervention for mitigating performance decrements on real-world tasks, especially when its onset is not linked with physiological indicators of inattention.

Response time analysis in cognitive tasks with increasing difficulty

In the present study, speeded tasks with differing assumed difficulties of the trials are regarded as a special class of simple cognitive tasks. Exploratory latent growth modeling with data-driven shape of a growth curve and nonlinear structured latent curve modeling with predetermined monotonically increasing functions were used to analyze individual response-time change with an increase in task difficulty and to investigate latent response-time growth variables in relation to cognitive ability. A task that required participants to state the number of dots in a set was used as an example of a simple cognitive task with increasing difficulty; the response latencies obtained in this task and the magnitude of RT-IQ correlations changed depending on the complexity of the trial.Consistent with theoretical predictions, the individual speed of baseline performance was only weakly negatively correlated with each of the three measures of cognitive ability used in the study. The rate of change in response times with increasing task difficulty, estimated as a generalized growth parameter in the exploratory latent growth model, was significantly negatively related to cognitive ability. Response times of less intelligent individuals increased more rapidly in the task with increasing difficulty than the response times of highly intelligent individuals. Within the nonlinear structured latent curve modeling, the growth of response times with an increase in task difficulty was best described by a function that approached an oblique asymptote after an initial interval of convexity. A slope of this oblique asymptote was significantly negatively related to cognitive ability; for less intelligent individuals, the asymptote of response-time change was steeper than that for more intelligent individuals. In addition, a parameter that determined the shape of response-time growth trajectories on the interval of convexity was related to one of the three measures of cognitive ability.

Haploinsufficiency of the E3 ubiquitin ligase C-terminus of heat shock cognate 70 interacting protein (CHIP) produces specific behavioral impairments.

The multifunctional E3 ubiquitin ligase CHIP is an essential interacting partner of HSP70, which together promote the proteasomal degradation of client proteins. Acute CHIP overexpression provides neuroprotection against neurotoxic mitochondrial stress, glucocorticoids, and accumulation of toxic amyloid fragments, as well as genetic mutations in other E3 ligases, which have been shown to result in familial Parkinson's disease. These studies have created a great deal of interest in understanding CHIP activity, expression and modulation. While CHIP knockout mice have the potential to provide essential insights into the molecular control of cell fate and survival, the animals have been difficult to characterize in vivo due to severe phenotypic and behavioral dysfunction, which have thus far been poorly characterized. Therefore, in the present study we conducted a battery of neurobehavioral and physiological assays of adult CHIP heterozygotic (HET) mutant mice to provide a better understanding of the functional consequence of CHIP deficiency. We found that CHIP HET mice had normal body and brain weight, body temperature, muscle tone and breathing patterns, but do have a significant elevation in baseline heart rate. Meanwhile basic behavioral screens of sensory, motor, emotional and cognitive functions were normative. We observed no alterations in performance in the elevated plus maze, light-dark preference and tail suspension assays, or two simple cognitive tasks: novel object recognition and spontaneous alternation in a Y maze. Significant deficits were found, however, when CHIP HET mice performed wire hang, inverted screen, wire maneuver, and open field tasks. Taken together, our data indicate a clear subset of behaviors that are altered at baseline in CHIP deficient animals, which will further guide whole animal studies of the effects of CHIP dysregulation on cardiac function, brain circuitry and function, and responsiveness to environmental and cellular stress.

Neural correlates of the difference between working memory speed and simple sensorimotor speed: an fMRI study.

The difference between the speed of simple cognitive processes and the speed of complex cognitive processes has various psychological correlates. However, the neural correlates of this difference have not yet been investigated. In this study, we focused on working memory (WM) for typical complex cognitive processes. Functional magnetic resonance imaging data were acquired during the performance of an N-back task, which is a measure of WM for typical complex cognitive processes. In our N-back task, task speed and memory load were varied to identify the neural correlates responsible for the difference between the speed of simple cognitive processes (estimated from the 0-back task) and the speed of WM. Our findings showed that this difference was characterized by the increased activation in the right dorsolateral prefrontal cortex (DLPFC) and the increased functional interaction between the right DLPFC and right superior parietal lobe. Furthermore, the local gray matter volume of the right DLPFC was correlated with participants' accuracy during fast WM tasks, which in turn correlated with a psychometric measure of participants' intelligence. Our findings indicate that the right DLPFC and its related network are responsible for the execution of the fast cognitive processes involved in WM. Identified neural bases may underlie the psychometric differences between the speed with which subjects perform simple cognitive tasks and the speed with which subjects perform more complex cognitive tasks, and explain the previous traditional psychological findings.

Brain responses in evaluating feedback stimuli with a social dimension

Previous studies on outcome evaluation and performance monitoring using gambling or simple cognitive tasks have identified two event-related potential (ERP) components that are particularly relevant to the neural responses to decision outcome. The feedback-related negativity (FRN), typically occurring 200–300 ms post-onset of feedback stimuli, encodes mainly the valence of outcome while the P300, which is the most positive peak between 200–600 ms, is related to various aspects of outcome evaluation. This study investigated the extent to which neural correlates of outcome evaluation involving perceptually complex feedback stimuli (i.e., female faces) are similar to those elicited by simple feedback. We asked participants to judge the attractiveness of blurred faces and then showed them unblurred faces as implicit feedback. The FRN effect can be identified in the ERP waveforms, albeit in a delayed 300–380 ms time window, with faces inconsistent with the initial judgment eliciting more negative-going responses than faces consistent with the judgment. However, the ERP waveforms did not show the typical pattern of P300 responses. With the principal component analysis (PCA), a clear pattern of P300 effects were revealed, with the P300 being more positive to faces consistent with the initial judgment than to faces inconsistent with the judgment, and more positive to attractive faces than to unattractive ones. The effect of feedback consistency did not interact with the effect of attractiveness in either the FRN or P300 component. These findings suggest that brain responses involved in processing complex feedback stimuli with a social dimension are generally similar to those involved in processing simple feedback stimuli in gambling or cognitive tasks, although appropriate means of data analysis are needed to reveal the typical ERP effects that may have been masked by sophisticated cognitive (and emotional) processes for complex stimuli.

Hyperthermic effects on behavior

This review focuses upon the past 8 years of research on hyperthermic effects on behavior. Heat stress and heat stoke become severe conditions when body temperatures exceed 40°C as this can lead to delirium, convulsions, coma, and death. The animal literature indicates that hyperthermia can increase glutamatergic and decrease GABAergic neurotransmission. Interestingly, µ-opiate receptor antagonists can attenuate the morphological and biochemical changes in brain, as well as, ameliorate some behavioral deficits induced by heart stress. In humans, heat stress can produce detrimental effects on motor and cognitive performance. Since most cognitive tasks require a motor response, some cognitive deficiencies may be attributed to decreased motor performance. Although hyperthermia may exert more deleterious effects on complex than simple cognitive tasks, systematic studies are needed to examine the effects of different levels and durations of hyperthermia (irrespective of dehydration) on cognition. Additionally, body temperatures should be carefully monitored where controls are run for baseline or brief exposures to a hyperthermic environment.Acute radiofrequency exposure can disrupt behavior when body temperatures increase >1°C with whole body SAR between 3.2–8.4 W/kg and time-averaged power densities at 8–140 mW/cm2. Effects of lower levels of radiation are conflicting and some experiments fail to replicate even with the original investigators. This suggests either that brief exposure to the radiation is at a threshold where some individuals are affected while others are not, or that these levels are innocuous. Nevertheless, thermal changes appear to account for almost all of the behavioral effects reported.