Limits on Introspection

Which cognitive processes are accessible to conscious report? To study the limits of conscious reportability, we designed a novel method of quantified introspection, in which subjects were asked, after each trial of a standard cognitive task, to estimate the time spent completing the task. We then applied classical mental-chronometry techniques, such as the additive-factors method, to analyze these introspective estimates of response time. We demonstrate that introspective response time can be a sensitive measure, tightly correlated with objective response time in a single-task context. In a psychological-refractory-period task, however, the objective processing delay resulting from interference by a second concurrent task is totally absent from introspective estimates. These results suggest that introspective estimates of time spent on a task tightly correlate with the period of availability of central processing resources.

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Evidence for Graded Central Processing Resources in a Sequential Movement Task

PsycEXTRA Dataset ◽

10.1037/e528942014-184 ◽

2014 ◽

Author(s):

Willem Bastiaan Verwey ◽

Elger Abrahamse ◽

Marit Ruitenberg

Keyword(s):

Central Processing ◽

Sequential Movement ◽

Processing Resources

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Effect of Complexity of the Second Response on Reaction Time to the First Response in the Psychological Refractory Period Paradigm

Perceptual and Motor Skills ◽

10.2466/pms.1987.64.3c.1075 ◽

1987 ◽

Vol 64 (3_suppl) ◽

pp. 1075-1080 ◽

Cited By ~ 2

Author(s):

Craig J. Chamberlin

Keyword(s):

Reaction Time ◽

Refractory Period ◽

Psychological Refractory Period ◽

Parallel Model ◽

Relative Complexity ◽

Central Processing ◽

Psychological Refractory Period Paradigm ◽

First Response ◽

Grouping Effect ◽

Flexible Model

An attempt to distinguish serial from parallel models of central processing was made by manipulating the relative complexity of R2 and observing the effect of this manipulation on RT1 in the Psychological Refractory Period paradigm. 14 subjects performed under two conditions, either a simple or complex R2. Experimental controls were used to prevent a possible grouping effect of responses. The results did not support a parallel model of central processing but did support a serial view. Implications of results, combined with previous findings, for a more flexible model of central processing were discussed.

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Effect of Physical Exhaustion on Cognitive Functioning

Perceptual and Motor Skills ◽

10.2466/pms.1997.84.1.291 ◽

1997 ◽

Vol 84 (1) ◽

pp. 291-298 ◽

Cited By ~ 26

Author(s):

Y-A. Féry ◽

A. Ferry ◽

A. Vom Hofe ◽

M. Rieu

Keyword(s):

Reaction Time ◽

Perceived Exertion ◽

Short Term Memory ◽

Strenuous Exercise ◽

Decision Task ◽

Short Term ◽

Physical Effort ◽

Difficult Decision ◽

Central Processing ◽

Processing Resources

Experiments utilizing reaction time to measure the effects of fatigue on cognition must discern sensitivity of peripheral and central processing to strenuous exercise. The additive factors method enables one to stipulate that if fatigue interacts with subjects' reaction time in a decision task, central processing is affected by fatigue. While pedaling at different intensities, 13 physically-fit men had to perform a series of short-term memory tests. The tests were executed during a constant workload session and a progressive workload session in which subjects pedaled until exhaustion. Subjects provided ratings on Borg's 1970 scale to measure the psychological effects of the physical effort such as perceived exertion. Allocation of processing resources was also measured to determine attentional constraints exerted by the dual-task situation. Analysis showed that decision reaction time was affected only during the exhausting bout of the progressive workload session and for the more difficult decision task. We discuss our results in the context of arousal and the allocation of processing resources.

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New Optimal Solutions for Real-Time Reconfigurable Periodic Asynchronous Operating System Tasks with Minimizations of Response Time

International Journal of System Dynamics Applications ◽

10.4018/ijsda.2012100105 ◽

2012 ◽

Vol 1 (4) ◽

pp. 88-131 ◽

Cited By ~ 2

Author(s):

Hamza Gharsellaoui ◽

Mohamed Khalgui ◽

Samir Ben Ahmed

Keyword(s):

Response Time ◽

Real Time ◽

Scheduling Algorithm ◽

Processing Unit ◽

Software Faults ◽

Worst Case ◽

Agent Based ◽

Central Processing ◽

Technical Solutions ◽

Task Systems

Scheduling tasks is an essential requirement in most real-time and embedded systems, but leads to unwanted central processing unit (CPU) overheads. The authors present a real-time schedulability algorithm for preemptable, asynchronous and periodic reconfigurable task systems with arbitrary relative deadlines, scheduled on a uniprocessor by an optimal scheduling algorithm based on the earliest deadline first (EDF) principles and on the dynamic reconfiguration. A reconfiguration scenario is assumed to be a dynamic automatic operation allowing addition, removal or update of operating system’s (OS) functional asynchronous tasks. When such a scenario is applied to save the system at the occurrence of hardware-software faults, or to improve its performance, some real-time properties can be violated. The authors propose an intelligent agent-based architecture where a software agent is used to satisfy the user requirements and to respect time constraints. The agent dynamically provides precious technical solutions for users when these constraints are not verified, by removing tasks according to predefined heuristic, or by modifying the worst case execution times (WCETs), periods, and deadlines of tasks in order to meet deadlines and to minimize their response time. They implement the agent to support these services which are applied to a Blackberry Bold 9700 and to a Volvo system and present and discuss the results of experiments.

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The Hyperfocusing Hypothesis: A New Account of Cognitive Dysfunction in Schizophrenia

Schizophrenia Bulletin ◽

10.1093/schbul/sbz063 ◽

2019 ◽

Vol 45 (5) ◽

pp. 991-1000 ◽

Cited By ~ 6

Author(s):

Steven J Luck ◽

Britta Hahn ◽

Carly J Leonard ◽

James M Gold

Keyword(s):

Working Memory ◽

Cognitive Processes ◽

Cognitive Deficits ◽

Term Outcome ◽

Long Term Outcome ◽

Good Target ◽

Processing Resources ◽

Nonspecific Factors ◽

New Treatments

Abstract Impairments in basic cognitive processes such as attention and working memory are commonly observed in people with schizophrenia and are predictive of long-term outcome. In this review, we describe a new theory—the hyperfocusing hypothesis—which provides a unified account of many aspects of impaired cognition in schizophrenia. This hypothesis proposes that schizophrenia involves an abnormally narrow but intense focusing of processing resources. This hyperfocusing impairs the ability of people with schizophrenia to distribute attention among multiple locations, decreases the number of representations that can simultaneously be maintained in working memory, and causes attention to be abnormally captured by irrelevant inputs that share features with active representations. Evidence supporting the hyperfocusing hypothesis comes from a variety of laboratory tasks and from both behavioral and electrophysiological measures of processing. In many of these tasks, people with schizophrenia exhibit supranormal effects of task manipulations, which cannot be explained by a generalized cognitive deficit or by nonspecific factors such as reduced motivation or poor task comprehension. In addition, the degree of hyperfocusing in these tasks is often correlated with the degree of impairment in measures of broad cognitive function, which are known to be related to long-term outcome. Thus, the mechanisms underlying hyperfocusing may be a good target for new treatments targeting cognitive deficits in schizophrenia.

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Line of Sight Correction of High-Speed Liquid Crystal Using Overdriving Technology

Electronics ◽

10.3390/electronics9091477 ◽

2020 ◽

Vol 9 (9) ◽

pp. 1477

Author(s):

Hongyang Guo ◽

Qing Li ◽

Yangjie Xu ◽

Yongmei Huang ◽

Shengping Du

Keyword(s):

Liquid Crystal ◽

Response Time ◽

High Speed ◽

Pulse Width Modulation ◽

Response Speed ◽

Line Of Sight ◽

Processing Unit ◽

Driving Voltage ◽

Light Modulator ◽

Central Processing

In the line of sight correction system, the response time of the liquid crystal spatial light modulator under the normal driving voltage is too long to affect system performance. On the issues, an overdriving method based on a Field-Programmable Gate Array (FPGA) is established. The principle of the overdrive is to use a higher voltage difference to achieve a faster response speed of liquid crystal. In this scheme, the overdriving look-up table is used to seek the response time of the quantized phase, and the liquid crystal electrode is driven by Pulse–Width Modulation (PWM). All the processes are performed in FPGA, which releases the central processing unit (CPU) memory and responds faster. Adequate simulations and experiments are introduced to demonstrate the proposed method. The overdriving experiment shows that the rising response time is reduced from 530 ms to 34 ms, and the falling time is from 360 ms to 38 ms under the overdriving voltage. Typical light tracks are imitated to evaluate the performance of the line of sight correction platform. Results show that using the overdrive the −3 dB rejection frequency was increased from 1.1 Hz to 2.6 Hz. The suppression ability of the overdrive is about −20 dB at 0.1 Hz, however the normal-driving suppression ability is only about −13 dB.

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Vestibular Stimulation Modulates Neural Correlates of Own-body Mental Imagery

Journal of Cognitive Neuroscience ◽

10.1162/jocn_a_01496 ◽

2020 ◽

Vol 32 (3) ◽

pp. 484-496 ◽

Cited By ~ 3

Author(s):

Manuel P. Klaus ◽

Gerda C. Wyssen ◽

Sebastian M. Frank ◽

Wilhelm M. Malloni ◽

Mark W. Greenlee ◽

...

Keyword(s):

Cognitive Processes ◽

Parietal Lobe ◽

Cognitive Task ◽

Vestibular Stimulation ◽

Neural Correlates ◽

Inferior Parietal Lobe ◽

Caloric Vestibular Stimulation ◽

Neural Integration ◽

Vestibular Information ◽

Main Effects

There is growing evidence that vestibular information is not only involved in reflexive eye movements and the control of posture but it also plays an important role in higher order cognitive processes. Previous behavioral research has shown that concomitant vestibular stimuli influence performance in tasks that involve imagined self-rotations. These results suggest that imagined and perceived body rotations share common mechanisms. However, the nature and specificity of these effects remain largely unknown. Here, we investigated the neural mechanisms underlying this vestibulocognitive interaction. Participants ( n = 20) solved an imagined self-rotation task during caloric vestibular stimulation. We found robust main effects of caloric vestibular stimulation in the core region of the vestibular network, including the rolandic operculum and insula bilaterally, and of the cognitive task in parietal and frontal regions. Interestingly, we found an interaction of stimulation and task in the left inferior parietal lobe, suggesting that this region represents the modulation of imagined body rotations by vestibular input. This result provides evidence that the inferior parietal lobe plays a crucial role in the neural integration of mental and physical body rotation.

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Drawing links between the autism cognitive profile and imagination: Executive function and processing bias in imaginative drawings by children with and without autism

Autism ◽

10.1177/1362361316668293 ◽

2016 ◽

Vol 22 (2) ◽

pp. 149-160 ◽

Cited By ~ 3

Author(s):

Kayla D Ten Eycke ◽

Ulrich Müller

Keyword(s):

Executive Function ◽

Cognitive Processes ◽

Cognitive Task ◽

Children With Autism ◽

Older Children ◽

Processing Style ◽

Mental Age ◽

Drawing Task ◽

Processing Bias ◽

Global Bias

Little is known about the relation between cognitive processes and imagination and whether this relation differs between neurotypically developing children and children with autism. To address this issue, we administered a cognitive task battery and Karmiloff-Smith’s drawing task, which requires children to draw imaginative people and houses. For children with autism, executive function significantly predicted imaginative drawing. In neurotypically developing controls, executive function and cognitive-perceptual processing style predicted imaginative drawing, but these associations were moderated by mental age. In younger (neurotypically developing) children, better executive function and a local processing bias were associated with imagination; in older children, only a global bias was associated with imagination. These findings suggest that (a) with development there are changes in the type of cognitive processes involved in imagination and (b) children with autism employ a unique cognitive strategy in imaginative drawing.

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