Fractionated Reaction Times and Movement Times of Down Syndrome and Other Adults with Mental Retardation

1991 ◽  
Vol 8 (3) ◽  
pp. 221-233 ◽  
Author(s):  
Walter E. Davis ◽  
William A. Sparrow ◽  
Terry Ward
Keyword(s):  
Down Syndrome ◽  
Mental Retardation ◽  
Reaction Time ◽  
Time Delay ◽  
Movement Time ◽  
Reaction Times ◽  
Elbow Extension ◽  
Total Reaction ◽  
Time Motor ◽  
Total Reaction Time

A fractionation technique was employed to determine the locus of reaction time delay in Down syndrome (DS) and other adult subjects with mental retardation (MH). Twenty-three subjects (8 nondisabled, 8 MH, and 7 DS) responded to a light, sound, and combination light/sound signal. Dependent measures of premotor time, motor time, total reaction time, and movement time were obtained during a 20° elbow extension movement and were analyzed separately. As expected, both MH and DS subjects were slower and more variable in their responses than the subjects without disabilities. In turn, DS subjects were significantly slower but not more variable than the MH subjects. There were no significant differences between the DS and MH subjects on movement times. Evidence for both a specific (premotor) and a generalized (both premotor and motor) locus of delay was found. Some difference in signal effect was also found for the DS subjects.

Determination Of Reaction Time Changes Per Time Unit In Clot Assays

1981 ◽  
Author(s):  
Lj Popović
Keyword(s):  
Reaction Time ◽  
Standard Sample ◽  
Reaction Times ◽  
Test Sample ◽  
Total Reaction ◽  
The Difference ◽  
Time Changes ◽  
Total Reaction Time

Changes in reaction time of clot assays are usually expressed only in time units, which fails to indicate the extent of the increase or decrease of the reaction time of the tested specimens against that of the basic sample. Reaction time increases of, e.g. , 6 seconds in tested samples, compared to basic sample reaction times of 12 and 24 seconds respectively, signify an increase twice as large in the first as in the second instance.Changes in reaction time of clot assays can be expressed as the increment or decrement of the reaction time per time unit. This amount of increase or decrease (positive or negative alteration of reaction time, T a ) can be expressed as the quotient of the difference between the reaction times of the tested (T x ) and basic (To) samples and of the basic sample, e.g. in seconds per second, T a =T x -To/To. A test sample reaction time 6 seconds longer than basic sample reaction times of 12 and 2k seconds would mean an increase of 0.5 and 0.25 seconds per second, respectively.Reaction time changes of tested samples against that of the standard sample (T std ) can be calculated in a similar way, T a =T x -T std /T std .It can be assumed that this parameter reflects the intensity of the increase or decrease of reaction time per time unit. The quotient of the tested and basic samples can be considered as the coefficient of the increase or decrease of the total reaction time (CT=T x /To).

Simple Reaction Times and Timing of Serial Reactions of Adolescents with Mental Retardation, Autism, and down Syndrome

1995 ◽  
Vol 81 (3) ◽  
pp. 739-745 ◽  
Author(s):  
Nobuyuki Inui ◽  
Masah Yamanishi ◽  
Shinji Tada
Keyword(s):  
College Students ◽  
Down Syndrome ◽  
Mental Retardation ◽  
Reaction Time ◽  
Reaction Times ◽  
Mentally Retarded ◽  
Tracking Task ◽  
The Other ◽  
Simple Reaction ◽  
Adolescents With Autism

The purpose of this study was to examine the serial information processing in adolescents with mental retardation, autism, and Down syndrome by using a serially patterned tracking task. Analyses indicated that 7 adolescents with mental retardation, 8 with autism, and 3 with Down syndrome had significantly slower and more variable simple reaction times than did 10 college students. Also, the autistic adolescents had significantly faster mean simple reaction time than those with Down syndrome. On a task of tracking serial light stimulation, mentally retarded adolescents had significantly faster reaction time than college students. The autistic subjects excessively had faster anticipatory reaction times than did the subjects in the other three groups. On the other hand, adolescents with Down syndrome had markedly slower and more variable reaction times than did adolescents with non-Down-syndrome mental retardation. As for motor organization of keystrokes on the tracking task, mentally retarded adolescents responded with six movements, in which these individuals pressed a series of keys 1, 2, 3, 4, 5, and 6, as a chunk, as exhibited by college students. Adolescents with autism and Down syndrome, however, did not produce this movement-output chunking.

Reaction Times for Simple Shape Discriminations Requiring One or Both Visual Cortices

1967 ◽  
Vol 19 (1) ◽  
pp. 70-72 ◽  
Author(s):  
G. S. Brindley ◽  
R. H. S. Carpenter ◽  
D. N. Rushton
Keyword(s):  
Reaction Time ◽  
Reaction Times ◽  
Shape Discrimination ◽  
Simple Shape ◽  
Total Reaction ◽  
Visual Cortices ◽  
The Difference ◽  
Total Reaction Time

Reaction times for a simple two-choice shape discrimination requiring either one or both visual cortices were measured. In a total reaction time of around 400 millisec. the difference found was 3.0 ± 2.6 millisec. If subjects were weighted according to number of observations, and — 1.34 ± 1.68 millisec. if they were weighted according to reciprocals of variances of differences of means; that is, it was not significant.

Effects of Midline Crossing on Reaction Time and Movement Time with Adolescents Classified as Mildly Mentally Retarded

1993 ◽  
Vol 10 (3) ◽  
pp. 269-280 ◽  
Author(s):  
Bobby L. Eason ◽  
Paul R. Surburg
Keyword(s):  
Factor Analysis ◽  
Mental Retardation ◽  
Reaction Time ◽  
Sensory Integration ◽  
Movement Time ◽  
Assessment Process ◽  
Mild Mental Retardation ◽  
Midline Crossing ◽  
Performance Deterioration ◽  
Temporal Assessment

Students with mild mental retardation (MMR) often demonstrate reluctance, confusion, or performance deterioration when required to perform tasks that require looking, reaching, or stepping across the body’s midline. Sensory integration theorists contend that midline crossing is a predictor of bilateral integration. However, in factor analysis studies, very little variance is accounted for by midline crossing data. The present study viewed midline crossing as a function of information processing and utilized a temporal assessment process rather than the usual spatial assessment process. Results indicated that subjects classified as MMR experienced slower choice reaction time (CRT) and movement time (MT) for stimuli placed across the body’s midline. However, higher functioning subjects with MMR performed equally well on CRT for ipsilateral and crosslateral tasks. The data provide evidence for a developmental hypothesis as an explanation for midline crossing problems.

scholarly journals Total Reaction Time Performance of Individuals with Autism after a Virtual Reality Task

2015 ◽  
Vol 02 (05) ◽  
Author(s):  
Dafne Herrero ◽  
Tânia Brusque Crocetta ◽  
Thais Massetti ◽  
Íbis Ariana Pena de Moraes ◽  
Isabela Lopes Trevizan ◽  
...  
Keyword(s):  
Virtual Reality ◽  
Reaction Time ◽  
Total Reaction ◽  
Time Performance ◽  
Reaction Time Performance ◽  
Total Reaction Time

scholarly journals Reactions under increased pressure: The reactivity of functionally substituted 3-oxo-2-arylhydrazones toward active methylene reagents in Q-tube

2021 ◽  
Vol 12 (2) ◽  
pp. 154-158
Author(s):  
Douaa Salman AlMarzouq
Keyword(s):  
High Pressure ◽  
Reaction Time ◽  
Reaction Times ◽  
Acid Ethyl Ester ◽  
One Pot ◽  
Two Component ◽  
Percentage Yield ◽  
Active Methylene ◽  
Total Reaction Time ◽  
Increased Pressure

A one-pot two-component reaction of 3-oxo-2-arylhydrazones with active methylene nitriles under high pressure in a Q-tube safe reactor was reported. Comparison between conventional and Q-tube safe reactor-assisted synthesis of organic compounds was done by comparing total reaction time and percentage yield. The results show that the compound 5-cyano-6-oxo-1,4-diphenyl-1,6-dihydro-pyridazine-3-carboxylic acid ethyl ester (3) was synthesized within 2 h in a yield of 97%. In addition, the pyrazolo[3,4-c]pyridines 5b and 5c were obtained in yields of 93 and 95% within 1 h reaction time, respectively. The obtained results suggest that Q-tube safe reactor-assisted syntheses were led to higher product yields within very short reaction times.

Rolling balance board of adjustable geometry as a tool to assess balancing skill and to estimate reaction time delay

2021 ◽  
Vol 18 (176) ◽  
Author(s):  
Csenge A. Molnar ◽  
Ambrus Zelei ◽  
Tamas Insperger
Keyword(s):  
Reaction Time ◽  
Time Delay ◽  
Feedback Control ◽  
Mechanical Model ◽  
Human Subjects ◽  
Reaction Times ◽  
Physical Parameters ◽  
Stabilizing Feedback Control ◽  
Model Subject ◽  
Balance Board

The relation between balancing performance and reaction time is investigated for human subjects balancing on rolling balance board of adjustable physical parameters: adjustable rolling radius R and adjustable board elevation h . A well-defined measure of balancing performance is whether a subject can or cannot balance on balance board with a given geometry ( R , h ). The balancing ability is linked to the stabilizability of the underlying two-degree-of-freedom mechanical model subject to a delayed proportional–derivative feedback control. Although different sensory perceptions involve different reaction times at different hierarchical feedback loops, their effect is modelled as a single lumped reaction time delay. Stabilizability is investigated in terms of the time delay in the mechanical model: if the delay is larger than a critical value (critical delay), then no stabilizing feedback control exists. Series of balancing trials by 15 human subjects show that it is more difficult to balance on balance board configuration associated with smaller critical delay, than on balance boards associated with larger critical delay. Experiments verify the feature of the mechanical model that a change in the rolling radius R results in larger change in the difficulty of the task than the same change in the board elevation h does. The rolling balance board characterized by the two well-defined parameters R and h can therefore be a useful device to assess human balancing skill and to estimate the corresponding lumped reaction time delay.

A Model of Human Reaction Time to Dangerous Robot Arm Movements

1987 ◽  
Vol 31 (2) ◽  
pp. 191-195 ◽  
Author(s):  
Martin G. Helander ◽  
Mark H. Karwan ◽  
John Etherton
Keyword(s):  
Decision Making ◽  
Reaction Time ◽  
Motor Response ◽  
Arm Movements ◽  
Robot Arm ◽  
Total Reaction ◽  
Human Reaction ◽  
Arm Motion ◽  
Human Reaction Time ◽  
Total Reaction Time

An increasing number of studies indicate that robots are the most hazardous equipment in industry. The very virtue that makes them attractive for industrial work, the programmable arm, is the cause of accidents since the arm motion is often difficult to perceive. The present paper presents a model of human reaction time and emergency behavior. The total reaction time is the sum of three elements: perception, decision making and motor response. Each of these three elements are modeled using concepts such as perceptual discriminability and single detection theory. Finally the results of an experiment is presented where the human reaction time is modeled as a function of robot arm speed.

scholarly journals Optimization of the qPCR temperature profile is essential for efficient and rapid detection of Sars-CoV-2

2021 ◽  
Author(s):  
Pál Salamon ◽  
Emese Bálint ◽  
Gyöngyi Tar ◽  
Beáta Albert
Keyword(s):  
Reaction Time ◽  
Binding Site ◽  
Temperature Profile ◽  
Rapid Detection ◽  
Target Gene ◽  
Target Product ◽  
Detection Time ◽  
Specific Detection ◽  
Total Reaction ◽  
Total Reaction Time

Abstract qPCR protocols should specify shorter annealing and extension times to optimize the efficacy of the target product. These specific times must be long enough for the complexes to form at the correct binding site, but if these times are too long, it can result in unspecified products. Our results show that reducing the reaction time during the second cycle can increase the specificity of the resulting product and thus reduce the total reaction time. The overall temperature profile, optimized for the target gene, shortens the detection time, allowing faster and more specific detection of the presence of the Sars-CoV-2.

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