Measures Of Perceptual Speed Research Articles

Processing speed can monitor stimulant-medication effects in adults with attention deficit disorder with hyperactivity

Background: Treatment responses to methylphenidate by adults with ADHD are generally monitored against DSM-IV/DSM-V symptomatology, rating scales or interviews during reviews.Aims: To evaluate the use of single- and dual-dimension processing-speed and efficiency measures to monitor the effects of pharmacological treatment with methylphenidate after a short period off medication.Methods: A Quick Test of Cognitive Speed (AQT) monitored the effects of immediate-release methylphenidate in 40 previously diagnosed and medicated adults with ADHD. Processing speed was evaluated with prior prescription medication, without medication after a 2-day period off ADHD medication, and with low-dose (10/20 mg) and high-dose (20/40 mg) methylphenidate hydrochloride (Medikinet IR).Results: Thirty-three participants responded to the experimental treatments. One-way ANOVA with post-hoc analysis (Scheffe) indicated significant main effects for single dimension colour and form and dual-dimension colour–form naming. Post-hoc analysis indicated statistical differences between the no- and high-dose medication conditions for colour and form, measures of perceptual speed. For colour–form naming, a measure of cognitive speed, there was a significant difference between no- and low-dose medication and between no- and high-dose medications, but not between low- and high-dose medications.Conclusions: Results indicated that the AQT tests effectively monitored incremental effects of the methylphenidate dose on processing speed after a 2-day period off medication. Thus, perceptual (colour and form) and cognitive speed (two-dimensional colour–form naming) and processing efficiency (lowered shift costs) increased measurably with high-dose medication. These preliminary findings warrant validation with added measures of associated behavioural and cognitive changes.

Effects of consuming an iron‐biofortified bean on behavioral and electrophysiological measures of attention

Iron deficiency (ID) can produce deficits in cognition and brain dynamics, and repletion may reverse these changes. We conducted a double‐blind efficacy study involving healthy female students (n = 239) screened for low iron status. Participants were randomized to groups that consumed either a high‐iron‐biofortified (BB) or a normal‐iron bean (CN) for 20 weeks. A subsample (n = 53) performed cognitive tasks while concurrent EEG was acquired at baseline (BL), endline (EL), and at one of eight random time‐points in between. Cognitive tasks included (a) a measure of perceptual speed (simple reaction time, SRT); (b) a test of inhibitory control (go/no‐go, GNG); and (c) an assessment of three aspects of attention (attentional network task, ANT). Small but significant improvements from BL to EL were observed for hemoglobin, ferritin, and total body iron, with larger improvements for the BB vs CN group. Behaviorally, there were no improvements in the SRT, possibly reflecting a floor‐effect. Significant condition (BB, CN) x time interactions were obtained for the behavioral measures from the GNG and ANT. The EEG data revealed significant differential increases for the BB vs CN group in the amplitudes of two components (N1 and P2), and normalized spectral power in two frequency ranges (alpha and gamma) that index aspects of attention in all three tasks. The results suggest that consuming BB may benefit behavior and brain function.

The Shortened Visuospatial Questionnaire for Children: A Useful Tool to Identify Students With Low Visuospatial Abilities

The current research was aimed mainly at exploring the reliability of a short-screening tool developed to self-evaluate visuospatial abilities in children. We presented 290 Italian third, fourth, and fifth graders with the 16-item Shortened Visuospatial questionnaire and several objective measures of intellectual efficiency, such as Raven's Coloured Progressive Matrices test, and verbal meaning, spatial relations, and perceptual speed measures based on the Primary Mental Abilities Battery. At the same time, a corresponding 18-item Shortened Visuospatial questionnaire was administered to teachers. Results show a sufficient connection between the visuospatial index of the Shortened Visuospatial questionnaire for children, its counterpart developed for teachers, and objective measures of intellectual efficiency. Finally, Raven's Coloured Progressive Matrices score accurately predicted the visuospatial index of the Shortened Visuospatial questionnaire completed by children. In conclusion, the Shortened Visuospatial questionnaire is a rapid and reliable tool for the early screening of visuospatial deficits.

Education Desegregation and Cognitive Change in African American Older Adults.

The present study examined the relationship between desegregated schooling and cognitive change in a sample of 420 community-dwelling African American elders (mean age = 68.6; SD = 9.1). Participants were recruited for the Baltimore Study of Black Aging - Patterns of Cognitive Aging. Cognitive measures from six domains of function were administered at baseline and follow-up 33 months later. Repeated measures multivariate analysis of covariance was conducted; the between subjects factors were schooling type and age cohort, and the within subjects factor was time. Analyses controlled for age, years of education, and sex, and follow-up univariate analyses were used to determine which individual cognitive scores drove the multivariate effects. There were significant multivariate within-group, between-group, and interaction effects (p < .05). Univariate analyses indicated that the desegregated schooling group scored significantly better on Language and Perceptual Speed (p < .01), and the youngest age cohort (50- to 59-year-olds) performed better on measures of Perceptual Speed. There were no significant univariate interactions between schooling group or age cohort and cognitive change over time. Overall, these findings suggest a slight advantage of desegregated schooling for cognitive performance, but no advantage of desegregated schooling on the rate of cognitive change over time in this sample.

Changes in perceptual speed and white matter microstructure in the corticospinal tract are associated in very old age

The integrity of the brain's white matter is important for neural processing and displays age-related differences, but the contribution of changes in white matter to cognitive aging is unclear. We used latent change modeling to investigate this issue in a sample of very old adults (aged 81–103years) assessed twice with a retest interval of 2.3years. Using diffusion-tensor imaging, we probed white matter microstructure by quantifying mean fractional anisotropy and mean diffusivity of six major white matter tracts. Measures of perceptual speed, episodic memory, letter fluency, category fluency, and semantic memory were collected. Across time, alterations of white matter microstructure in the corticospinal tract were associated with decreases of perceptual speed. This association remained significant after statistically controlling for changes in white matter microstructure in the entire brain, in the other demarcated tracts, and in the other cognitive abilities. Changes in brain volume also did not account for the association. We conclude that white matter microstructure is a potent correlate of changes in sensorimotor aspects of behavior in very old age, but that it is unclear whether its impact extends to higher-order cognition.

Cognitive Functioning and Sex Steroid Hormone Gene Polymorphisms in Women at Midlife

Single nucleotide polymorphism (SNP) genotype frequencies were examined to determine whether variation in 6 estrogen-related genes was associated with differences in cognitive functioning in women at midlife. DNA from a multiracial/multiethnic sample of 875 African American, Caucasian, Chinese, and Japanese women aged 45 to 56 years participating in the Study of Women’s Health Across the Nation (SWAN) was genotyped. Gene markers from the sex steroid hormone pathway were linked to measures of cognitive functioning including the Digit Span Backward Test (DSB), a measure of working memory; the Symbol Digit Modalities Test (SDMT), a measure of perceptual speed; and the East Boston Memory Test (EBMT), a measure of episodic memory. Statistical models were fit using logistic regression and general linear models to estimate the strength of association of estrogen-related polymorphisms with DSB, SDMT, and EBMT scores. On the EBMT, African American women and Caucasian women with ESR1 rs9340799 GG genotypes had about 1.5 to 2.0 times greater odds of remembering story elements on the EBMT-immediate recall test. Caucasian women with ESR1 rs2234693 CC genotypes had 1.3 to 1.5 times greater odds of remembering story elements on the EBMT-delayed recall test. Chinese women with 17HSD rs615942 GG genotypes, 17HSD rs592389 TT genotypes, and 17HSD rs2830 GG genotypes had about 1.7 times greater odds of remembering story elements on the EBMT-immediate recall test. African American women with CYP 19 rs936306 CC genotypes had about 0.25 to 0.40 lower odds of remembering story elements on the EBMT-immediate recall test, whereas Chinese women with CYP 19 rs936306 CC genotypes had about 2.3 times greater odds of remembering story elements on both the EBMT-immediate and -delayed recall tests. On the DSB, African American women with CYP 19 rs749292 GG genotype had a higher mean score. On the SDMT, Japanese women with ESR1 rs728524 GG genotypes had a higher mean score. On the 3 tests of cognitive functioning, there was 1 significant finding for CYP1A1 and none for the CYP1B1 or ESR2 SNPs. We conclude that selected genes involved in estrogen synthesis and metabolism may be associated with performance differences on cognitive function tests. Also, the relevant estrogen-related polymorphisms may vary by race/ethnicity.

Depressive symptoms, quality of life, and neuropsychological performance in HIV/AIDS: The impact of gender and injection drug use

Limited attention has been paid to the potential impact of gender and injection drug use (IDU) on mood, quality of life, and neuropsychological performance in human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS). Several studies that describe the natural history of HIV/AIDS in terms of mental health and neuropsychological ability have focused solely on men or have excluded injection drug users. Women and injection drug users are two groups for whom the incidence of HIV infection is increasing. Additionally, the National Academy of Sciences recently recommended that studies concerned with health-related research include males and females, and that researchers analyze their data for gender differences. The goals of the current study were to investigate possible relationships between HIV and IDU status and depressive symptoms, quality of life, and neuropsychological performance in women and men matched for age, race, and education. Overall, women reported more depressive symptoms than men, and this gender difference was most evident in women who were both infected with HIV and who were also injection drug users. Women and HIV-infected individuals reported the poorest quality of life scores. Women outperformed men on a measure of verbal memory and HIV(-) participants outperformed HIV(+) participants on a measure of perceptual speed. Finally, gender and HIV status interacted such that uninfected women performed the best, and infected men performed the worst, on a test of verbal memory. A better understanding of how men and women with different drug use profiles respond to HIV/AIDS may substantially improve survival, as well as aspects of daily functioning, of affected individuals. Thus, further study and development of treatment protocols targeted at including women and IDU are needed.

IT, IQ and perceptual speed

Abstract Although it is now beyond dispute that measures of inspection time (IT) are significantly correlated with IQ scores, the basis of this association is less clear. One suggestion is that IT provides a measure of the biological basis of g. Another is that IT is simply associated with a factor of perceptual speed (Gs in the Horn–Cattell model), which is, of course, also associated with other IQ measures. Sixty-seven sixth-form students performed an IT task and were also given tests of vocabulary, abstract reasoning and perceptual speed. Forty-three also completed a test of spatial ability. IT correlated significantly only with measures of perceptual speed (0.43) and abstract reasoning (0.29) but the partial correlation between IT and reasoning was only 0.15 when perceptual speed was taken into account.

Cognitive, perceptual-speed, and psychomotor determinants of individual differences during skill acquisition.

The authors describe a series of experiments that explore 3 major ability determinants of individual differences in skill acquisition in the context of prior theory (e.g., P.L. Ackerman, 1988) and subsequent empirical and theoretical research. Experiment 1 assessed the predictability of individual differences in asymptotic skill levels on the Kanfer-Ackerman Air Traffic Controller (ATC) task. Experiment 2 provided an exploration of the construct space underlying perceptual-speed abilities. Experiment 3 concerned an evaluation of theoretical predictions for individual differences in performance over skill development in a complex air traffic control simulation task (TRACON) and the ATC task, with an extensive battery of general and perceptual-speed measures, along with a newly developed PC-based suite of psychomotor ability measures. Evidence addressing the predictability of individual differences in performance at early, intermediate, and asymptotic levels of practice is presented.

Shared age-related influences on cognitive and noncognitive variables.

Analyses of new data and of previously published data were conducted to examine the degree to which age-related variance was shared across cognitive and noncognitive variables and to investigate possible alterations in the composition of a factor common to all variables as a function of age. The results indicated that measures of visual acuity, grip strength, and blood pressure shared age-related variance with measures of perceptual speed, episodic memory, spatial visualization, and inductive reasoning. However, although the cognitive variables shared similar amounts of variance in age-restricted and age-partialed analyses, the variance shared between cognitive and noncognitive variables was substantially reduced after controlling the influence of age.

Challenging the “law of diminishing returns”

The law of diminishing returns ( Spearman, 1927) states that the size of the average correlation between cognitive tasks tends to be relatively small in high-ability groups and relatively high in low-ability groups. Studies supporting this finding have tended to contrast very low-ability subjects (IQ < 78) with subjects from higher ability ranges and to use tests that have poor discriminatory power among the higher ability levels. In the first study described in this article, tasks that provide good discrimination among the higher ability levels were used. A sample of high-ability ( N = 25) and of low-ability ( N = 20) 15-year-old boys completed four single tests, two with low and two with high g saturations, and two competing tasks formed from these single tests. The results indicated that, contrary to the predictions of the law of diminishing returns, the amount of common variance was greater in the high-ability group. It is suggested that the law of diminishing returns does not take into account the factor of task difficulty and that there are situations in which the exact reverse of this law holds. A second study again compared correlations obtained with extreme groups ( N = 28 and N = 29), this time on measures of perceptual speed, which are easy for all ability levels. Results indicated that correlations among the perceptual speed measures were the same for both groups. In neither of these studies was there any support for the law, which seems to be dependent on the very high correlations obtained from samples at the extreme lower end of the ability continuum.

Air force officer qualifying test validity for predicting pilot training performance

The AFOQT was validated for the prediction of pilot training criteria. Subjects were 7,563 men and women selected for pilot training on the basis of educational attainment and AFOQT scores. Criterion variables included daily flight training grades, check flight grades in subsonic and transonic aircraft, and overall academic performance in the 53 week pilot training course. Test validities were presented as observed, corrected for multivariate range restriction, and corrected for multivariate range restriction and unreliability. The Aviation Information and Instrument Comprehension tests, measures of job knowledge, were most predictive of daily and check flights in the initial subsonic jet aircraft. This reflects the relative greater importance of prior job knowledge early in training. The Scale Reading test, a measure of perceptual speed, was most predictive for daily and check flights in the advanced transonic training aircraft. The Arithmetic Reasoning test, a good measure of general cognitive ability, was most predictive of aeronautics in ground school. The development of an improved pilot selection composite is suggested by the results of the validity analyses.

Age-related differences in adults' spatial task performance: Influences of task complexity and perceptual speed

Abstract It was predicted that the magnitude of age differences in performance of a figure comparison task would increase as a function of task complexity, which was manipulated by varying the angular disparity between figural stimuli to be compared and by varying the number of line segments comprising those stimuli. It was further reasoned that if the anticipated effect was due primarily to age-related decline in perceptual speed, then a measure of perceptual speed would account for the majority of age-related variance in task performance. Findings supported the age-complexity hypothesis, but included the effect of sex and response criteria. Despite the fact that perceptual speed was a significant predictor of task performance for men, it did not account for a great deal of age-related variance in women's performance. Other results indicated that (a) subjects' performance in responding to “same” and “different” stimulus pairs varied as a function of angular disparity between figures, and (b) sex differen...

The nature of the influence of speed on adult age differences in cognition.

Two studies were conducted to determine the relations among age, motor speed, perceptual speed, and 3 measures of cognitive performance: study time, decision time, and decision accuracy. Each study involved over 240 adults between I 8 and over 80 years of age who all performed a battery of tests, including computer-administered tests of memory, reasoning, and spatial ability. The results indicated that (a) increased age was associated with lower accuracy as well as with longer study time and decision time and (b) some ofthe relations between age and decision accuracy and between age and decision time appear to be mediated by a slower rate ofexecuting cognitive operations. Considerable evidence now exists indicating that a large proportion ofthe age-related variance in many different cognitive variables is shared with a measure of perceptual speed. Among the most pertinent results are the findings that the age-related diffbrences in various measures of cognitive functioning are greatly reduced when statistical control procedures are used to adjust for differences in perceptual speed. As an illustration of this phenomenon, Thble I in Salthouse (1993b) contains 44 comparisons across a wide range of cognitive variables. Age was associated with a mean of l6.2Vo of the total variance in the variables, but after the variance associated with measures of perceptual speed was held constant, age was associated with only 3.6Vo ofthe variance in the cognitive variables.

Speed mediation of adult age differences in cognition.

Previous research has established that a large proportion of the adult age-related variance in various measures offluid or process cognition is reduced when statistical control procedures such as hierarchical regression are used to eliminate variation in measures ofperceptual speed. This finding was confirmed in the present study and was extended to include paired-associate and free-recall measures of memory in addition to measures of reasoning and spatial abilities. Most of the speed mediation was associated with speed measures requiring cognitive operations such as comparison or substitution instead of merely motor responses such as copying symbols or drawing lines. These results suggest that the rate of performing elementary cognitive operations is an important proximal mediator ofthe adult age differences in several types ofcognitive tasks. Inspired largely by ideas of Birren (e.g., 1955,1965,1974), Salthouse 0985a) proposed that the adult age differences in certain measures of cognitive functioning might be partially mediated by age-related reductions in the speed ofexecuting relevant mental operations. The evidence available at that time was rather weak, because no published studies had been explicitly designed to investigate this hypothesis. Most of the data relevant to the hypothesis were obtained by locating published articles reporting correlations among age, a measure of processing speed, and a measure of cognition (or studies by Salthouse containing the relevant data), and then computing partial correlations between age and the cognitive measure after partialing out the measure of speed. Only a few data sets with the necessary information could be identified, and the samples were often small and usually involved two extreme age groups rather than a continuous range of ages. Furthermore, in all cases the relevant constructs were assessed with a single measure rather than with potentially more reliable and valid multiple measures. Despite these limitations, the hypothesis received some support because statistical control of the measure ofspeed frequently resulted in an appreciable reduction in the magnitude of the relation between age and the measure of cognition.

One‐Month Repeatability of Emotional Responses to Alcohol

Thirty-four subjects in the Colorado Alcohol Research on Twins and Adoptees (CARTA) were brought back between 30 to 60 days after their initial testing to be retested on all the CARTA procedures. As before, subjects were given a dose of ethanol (0.8 g/kg) calculated to bring their blood alcohol concentration (BAC) to near 0.10 g/dl. Additional doses were given at the end of each of the next 2 hr to maintain their BAC near peak for approximately 3 hr. During both testings, subjects' self-reports of their emotional responses and perceived intoxication following alcohol dosing were only minimally correlated with their alcohol metabolism parameters and reported average level of alcohol use. Repeatabilities (test-retest correlations) for subjects' self-reports of positive affect and of intoxication following alcohol dosing were consistently high, in contrast to earlier reports of minimal repeatabilities for alcohol metabolism and responses to alcohol on physiological, motor coordination, reaction time, and perceptual speed measures. Tester ratings of the subjects' levels of intoxication were also moderately stable between the two testings.

PERCEPTUAL SPEED AND BEHAVIORAL PROFICIENCY.

Perceptual speed in specific sensory modalities should lead to efficiency in behaviors governed by these modalities. To test this hypothesis, correlations were computed between measures of perceptual speed and scores on a modified Stroop test. Those correlations relevant to the hypothesis were all significant and in the expected direction. The pattern of results is thus reasonably consonant with the hypothesis. Reserpine, which might be expected to affect the above relationships, was ineffective.