Brinley Plot Research Articles

Specific but not general declines in attention and executive function with aging: Converging cross-sectional and longitudinal evidence across the adult lifespan.

Attention and executive function (EF) are vulnerable to aging. However, whether all these functions generally decline with aging is not known. Furthermore, most evidence is based on cross-sectional data and fewer follow-up data are available in the literature. Longitudinal follow-up studies are necessary to characterize individualized and precise changes in cognitive function. Additionally, relatively few aging studies have included middle-aged adults to examine age-related differences in attention and EF. Therefore, this study aims to examine whether general or specific attention and EF decline with aging from adulthood to old age by combining cross-sectional and longitudinal follow-up approaches. This study recruited 253 participants aged 20 to 78 years. passing a prescreening procedure (see main text for detail) for the baseline session, and 123 of them were invited to return 1 ~ 2 years after their first visit to participate in the follow-up session. The participants completed a series of attention and EF tasks at both the baseline and follow-up sessions, which measured alerting, orienting, conflict control, stopping, memory updating, and switching abilities. We applied linear and nonlinear regression models to evaluate the cross-sectional age effect on attention and EF and employed a modified Brinley plot to inspect follow-up performance against baseline in attention and EF. The results of cross-sectional data showed that older adults exhibited decreased efficiency in alerting, stopping, and memory updating but paradoxically increased efficiency in conflict control and switching abilities and no changes in orienting efficiency with age. However, the results of longitudinal data showed that only alerting and memory updating continued to show decreased efficiency. Furthermore, conflict control and switching showed increased efficiency with aging, whereas the orienting network, and stopping no longer showed decreased efficiency. Thus, converging the cross-sectional and longitudinal data showed that the alerting and memory updating function exhibited the most robust deficit with age (cross-sectional) and aging (longitudinal). Alerting and memory updating abilities are crucial survival skills for human beings. Therefore, developing methods to prevent and improve an individual's alertness and working memory ability is an important practical issue in aging research.

The effect of age on task switching: updated and extended meta-analyses.

Cognitive flexibility is one of the crucial abilities for human survival. As people get older, whether their flexibility ability will be affected is one of the core research topics in aging research. Researchers have developed a task-switch paradigm in laboratories to mimic daily-life shifting task-set scenarios. However, the empirical evidence is equivocal. Considering every single study may have a biased sample; therefore, we hoped to combine smaller studies, making them into one extensive investigation, which may help show an actual effect. In the current study, we used two meta-analysis techniques, the Brinley plot (along with the State-trace plot) and conventional meta-analysis, to re-evaluate whether healthy aging influences cognitive flexibility. The results of the Brinley plot analysis showed no evidence of switch-specific age-related impairment as indexed by the local switch cost. Yet, older adults performed more slowly than younger adults across task conditions. The conventional meta-analysis further showed that the currently available findings were heterogenous and exhibited publication bias. Therefore, this study suggests that researchers should interpret their results cautiously while using a task-switching paradigm to address older adults' shifting abilities. More parametric variables must be considered and developed in a task-switching paradigm to enhance its sensitivity and reveal older adults' actual shifting ability.

A proposal for the assessment of replication of effects in single-case experimental designs.

In science in general and in the context of single‐case experimental designs, replication of the effects of the intervention within and/or across participants or experiments is crucial for establishing causality and for assessing the generality of the intervention effect. Specific developments and proposals for assessing whether an effect has been replicated or not (or to what extent) are scarce, in the general context of behavioral sciences, and practically null in the single‐case experimental designs context. We propose an extension of the modified Brinley plot for assessing how many of the effects replicate. To make this assessment possible, a definition of replication is suggested, on the basis of expert judgment, rather than on statistical criteria. The definition of replication and its graphical representation are justified, presenting their strengths and limitations, and illustrated with real data. A user‐friendly software is made available for obtaining automatically the graphical representation.

What Can Brinley Plots Tell Us About Cognitive Aging? Exploring Simulated Data and Modified Brinley Plots.

Cognitive aging researchers have been challenged with demonstrating age-related effects above and beyond global slowing ever since Cerella raised this issue in 1990. As the literature has made clear, this has indeed proved to be a difficult task and continues to plague the field. One way that researchers have attempted to test for disproportionate age differences across task conditions is by using Brinley plots, or plotting the mean response latencies of older adults against the mean latencies for younger adults. The simplicity and large proportion of variance accounted for by these models has led to the widespread use of Brinley plots over the years. However, as systematically tested here through eight cases of simulated data, it is clear that the Brinley technique is not well suited to either identify or display the underlying structure of datasets examining age-related differences in attentional control. Some of the problems with conventional Brinley plots can be resolved by using a modified Brinley plot that includes study-specific slopes linking trial types and a no-age-difference reference line. Multilevel models find all of the relevant effects, especially if applied to trial-level data, and have the advantage of incorporating study-level moderators that might account for slope heterogeneity. Ultimately, we encourage fellow cognitive aging researchers to access the code and data for this project on OSF (https://osf.io/zxus8/) and employ the use of multilevel models over Brinley plots.

Assessing Consistency in Single-Case Data Features Using Modified Brinley Plots.

The current text deals with the assessment of consistency of data features from experimentally similar phases and consistency of effects in single-case experimental designs. Although consistency is frequently mentioned as a critical feature, few quantifications have been proposed so far: namely, under the acronyms CONDAP (consistency of data patterns in similar phases) and CONEFF (consistency of effects). Whereas CONDAP allows assessing the consistency of data patterns, the proposals made here focus on the consistency of data features such as level, trend, and variability, as represented by summary measures (mean, ordinary least squares slope, and standard deviation, respectively). The assessment of consistency of effect is also made in terms of these three data features, while also including the study of the consistency of an immediate effect (if expected). The summary measures are represented as points on a modified Brinley plot and their similarity is assessed via quantifications of distance. Both absolute and relative measures of consistency are proposed: the former expressed in the same measurement units as the outcome variable and the latter as a percentage. Illustrations with real data sets (multiple baseline, ABAB, and alternating treatments designs) show the wide applicability of the proposals. We developed a user-friendly website to offer both the graphical representations and the quantifications.

Speed of Processing Time Slowing in Eating Disorders

ABSTRACTWe applied Brinley (1965) plot analysis to the eating disorders field. Across 23 studies and 165 experimental conditions [experienced by a total of 773 eating disorder (ED) participants, including anorexia nervosa (AN), binge eating (BE), bulimia nervosa (BN), and eating disorders not otherwise specified (EDNOS) and 995 controls], the best-fit regression equation was Y (ED) = 1.08 X (CONTROL) – 31. This equation accounted for 98.2% of the variance. Thus, the ED subjects were only 1.08 times slower than the control subjects, suggesting little processing speed slowing in ED. We also examined simple reaction time [SRT; Y (ED) = .91 X (CONTROL) + 63; variance accounted for = 93.6%] and choice reaction time (CRT; Y (ED) = 1.12X (CONTROL) – 43, variance accounted for = 99.7%). These slopes are significantly different. ED subjects are more impacted when the task involves a decision component (CRT) than when it does not (SRT).

Combining Movement Kinematics, Efficiency Functions, and Brinley Plots to Study Age-Related Slowing of Sensorimotor Processes: Insights from Fitts’ Task

Background: Measurement of changes in human information-processing capacities underlying slowing of sensorimotor processes is an important challenge for aging research. Methods exist to estimate the magnitude of slowing and variability coefficients, but attempts to apply them in motor tasks have been scarce. In the present experiment we combined movement kinematic analysis, efficiency functions and Brinley plot to assess age-related slowing and variability of sensorimotor processes in a discrete Fitts’ aiming task. Objectives: (1) Quantifying slowing and variability for the different sensorimotor processes involved in aiming movements, and (2) determining whether changes occurred continuously over time by comparing different age groups. Methods: 29 participants (24–90 years) divided into four age groups were tested. Target size manipulation resulted in three levels of difficulty. Total movement time, durations of the first and secondary movement phases and related variability were analyzed. Fitts and Brinley regression functions were calculated on the basis of the different movement variables. Results: Only older participants were slower than the three younger age groups. For this group, age-difficulty effect was observed for total movement times, but analyses showed that only the secondary movement phase slowed multiplicatively. Additive and proportional increases in variability were also observed in older participants for the first and secondary movement phases, respectively. For the secondary movement phase, estimated slowing coefficients were comparable to those reported in cognitive literature. In addition, Brinley analyses showed that variability increased more than movement time in the secondary movement phase. Discussion: Combination of the different methods of analysis allowed a precise assessment of the locus of slowing and variability of sensorimotor processes in the different movement phases. Results showed that significant changes in both slowing and variability of the different processes occurred late in life. Our findings also suggest that slowing could result from age-induced increase in noise produced by the neural system. Finally, the present results raise the question of whether age-related slowing and increase in variability observed in both cognitive and sensorimotor domains share common causes in the central nervous system.

Review of Arthur R. Jensen (2006)--Clocking the mind: Mental chronometry and individual differences.

Mental chronometry, as Arthur Jensen stresses, is study of reaction time (RT) in its various guises, contexts, and applications. As with respect to much of experimental psychology (cognitive and other), there is a venerable past here lying in background, providing a wide-ranging context in which to embed our current (that is, our 40-odd year) preoccupation with as a primary dependent measure in cognitive psychology. This recent book, Clocking Mind: Mental Chronometry and Individual Differences (published by Elsevier), weds both differential psychology's concern with measurement of individual differences in (e.g., Austin, Deary, Gibson, McGregor, & Dent, 1998) and experimental psychology's concern with the effects of manipulating various external conditions on variation in measurements of RT (p. 1). The reader of this journal will most probably be more familiar with latter use of in literature, especially when embedded within such familiar experimental tasks as those tapping both Garner and Stroop effects (Pansky & Algom, 1999). If this be case, then one might well be wondering why such a book is needed. After all, do we not all know how to measure and to use this profitably in our research? In answer, I would like to state that it is always instructive to read a book by a master of field. Arthur Jensen is, of course, well known for his contributions to study of intelligence, including (but not limited to) use of in this domain. The book comprises 14 chapters (272 pages), discussing history, terminology, and paradigms (first three chapters), continuing with measurement, developmental issues, cognitive aging and genetics (next four), focussing on individual differences in five subsequent chapters (dealing with psychometrics, correlating Chronometrie and psychometric measures, inspection time, and IQ, and relation of to other variables), and ending with two chapters discussing clinical and medical uses of and a plea for standardizing chronometry. To my mind, first half of book (until page 135) will be of use to a general audience, who have an interest in use of in research, while not necessarily being concerned with issue of individual differences. This notwithstanding, it is from vantage of study of individual differences (including psychometric considerations) that Jensen contributes some compelling thoughts regarding RT, some of which will certainly challenge experimental psychologist. I will elaborate on eight of these points - choosing five from first half and three from second half, but intermeshed below. These points are as follows, and discussed in this order: 1) standard measurement of RT, 2) use of additive factors in analyzing RT, 3) psychometric considerations for RT, 4) Brinley plot, mapping older (aging) onto younger RT, 5) use of regression parameters in chronometry, 6) ensuring independence of measures in multivariate analyses, 7) speed-accuracy trade-off for RT, and 8) brain-behaviour relationships and RT. I will exploit this platform to engage in debate with author. To begin with, even though this insight appears at end of book, standard practice of using a computer keyboard to measure comes under attack (Point 1): The four cursor keys are most frequently used. Because these keys are on right-hand side of keyboard, they possibly favor right-handed subjects... Subjects also find it distracting or confusing to have whole complex keyboard exposed when only a few keys are needed for particular task... Many obvious disadvantages of using a computer keyboard as response console make it least desirable choice for minimizing irrelevant and unwanted sources of variance in Chronometrie measurements, (p. 240) As Jensen indicates, experimental psychologists may well have introduced a source of systematic error into computerized lab. …

Proportional Slowing or Disinhibition in ADHD? A Brinley Plot Meta‐analysis of Stroop Color and Word Test Performance

A meta‐analysis in the form of Brinley plots was conducted on the mean reaction times of Attention Deficit Hyperactivity Disorder (ADHD) and Control groups of children and adolescents on the Stroop Color and Word Test (SCWT). ADHD reaction times were regressed on Control group reaction times for 17 data sets (accessed from 13 published studies). These analyses yielded linear functions (mean r2 = 0.997), with slopes typically greater than one (mean b = 1.288). The response time thus increases systematically by an inflation factor of approximately 29% in ADHD children and adolescents relative to increases in their Control peers across the three conditions of the SCWT. In additional analyses, for each Brinley plot, the deviation from the linear regression line of the data point for the critical Color‐Word condition was also calculated. There was only modest evidence that a deficit in inhibition exerts any influence on performance in this condition over and above that of general slowing for children and adolescents with ADHD. These results support the notion that a general slowing hypothesis provides a more parsimonious account of ADHD reaction times on the SCWT than that provided by the inhibition account previously thought to underpin findings in this area.

Neurocognitive dysfunction in antidepressant-free, non-elderly patients with unipolar depression: Alerting and covert orienting of visuospatial attention

Background Cognition is impaired across various domains in young and middle-age adults with unipolar depression. Performance appears in general worse in effortful tasks requiring executive function and attention. Probing specific cognitive operations in depressed patients, such as alerting and covert orienting of visuospatial attention, can better define and characterize the pathophysiology. Methods Nine antidepressant-free, clinically depressed patients and fourteen age-matched healthy subjects performed a Posner task with components of phasic alerting and covert orienting of visuospatial attention. Reaction times were analyzed by repeated-measures ANOVA with DIAGNOSIS as the between-group measure. Visual field (FIELD), stimulus onset asynchrony (SOA), and orienting CUE condition were within-subject, repeated measures. Results ANOVA showed intact attentional orienting in both groups. There were no FIELD differences across groups nor main effects of DIAGNOSIS. Interactions of DIAGNOSIS with SOA and DIAGNOSIS with CUE condition identified a phasic alerting deficit in the depressed patients. There were no significant effects of time-on-task, suggesting adequate vigilance or sustained attention in both groups. Plotting depressed versus control subjects' reaction time for each task condition (Brinley plot) showed linearity with a slope of 1.6 (i.e., patients were 1.6-fold slower) and a correlation coefficient of 0.98 (accounting for 96% of the overall variance). Limitations This study contains a small sample with potential for Type II error. The study addressed depression at the syndrome level. Depressed patients selected on particular symptom dimensions (e.g., anxiety, psychomotor retardation, etc.) could reveal abnormalities in hemisphere asymmetries that were not observed here. Conclusions These data highlight that global slowing is a major cognitive deficit in depression and arises across levels of difficulty. Putative specific deficits in depression need adjustment for the large effects of global slowing which can mimic selective impairments in more effortful task conditions.

Developmental trends in simple and selective inhibition of compatible and incompatible responses

This study examined age-related change in the ability to inhibit responses using two varieties of the stop signal paradigm. Three age groups (29 7-year-olds, 24 10-year-olds, and 28 young adults) performed first on a visual choice reaction task in which the spatial mapping between the go signal and response was varied between blocks. The choice task was then complicated by randomly inserting a visual stop signal on 30% of the trials. In the simple stop signal paradigm, the stop signal required the inhibition of the planned response. In the selective stop signal paradigm, the stop signal required response inhibition only when the stop signal was presented at the same side as the instructed response to the go signal. The results showed that simple stopping was faster than selective stopping and that selective, but not simple, stopping of incompatible responses was slower than stopping of compatible responses. Brinley plot analysis yielded linear functions relating children’s latencies to adults’ latencies. Analysis of shared variance indicated that developmental change in the speed of selective stopping continued to be significant even when the effect associated with simple stopping was removed. This pattern of findings is discussed vis-à-vis notions of global versus specific developmental trends in the speed of information processing.

Reaction Time Performance in Adults With HIV/AIDS

Infection with the Human Immunodeficiency Virus - Type 1 (HIV-1) has been shown to lead to cognitive decline in a substantial proportion of infected adults. The characteristic neuropsychological symptomatology includes memory dysfunction, higher order attentional disturbance, executive dysfunction and, most relevant to this manuscript, cognitive slowing. This paper reviews the extant literature on reaction time (RT) performance in HIV-infected adults with an emphasis on mental chronometry. In addition to discussing studies of simple and choice RT, we also examine the utility of RT paradigms in the assessment of selective attention, covert orienting, sustained attention, divided attention, working memory, and implicit memory. Studies documenting the utility of RT tasks to track treatment response are also introduced. In aggregate, research to date that has employed RT tasks in the evaluation of HIV-infected patients has found that HIV infection leads to a mild degree of cognitive slowing that tends to worsen with increasing disease severity. It needs to be noted, however, that a significant percentage of studies failed to find HIV infection to lead to RT slowing. Results of Brinley plot analyses, a technique that shares commonalities with meta-analysis, reveal that HIV-infected patients diagnosed with AIDS are on an average 22% slower than uninfected controls. This paper also reviews data that has shown that HIV associated cognitive slowing, as indexed by single and dual choice RT, is amenable to pharmacologic intervention using the psychostimulant methylphenidate. Given the demonstrated sensitivity of RT tasks to the neuropsychological effects of HIV infection, it is recommended that RT tasks be included whenever possible in the routine clinical evaluation of HIV-infected patients.

Developmental and individual differences in fluid intelligence: Evidence against the unidimensional hypothesis

The Brinley plot and partial correlation methods are used to investigate conjointly the theories that increasing speed of processing is responsible for changes in mental age (MA) and that speed of processing gives rise to within‐age differences in fluid intelligence (IQ). A group of 107 children ranging in age from 4 to 9 years completed three reaction time (RT) tasks (spatial, verbal and selective attention). Children were grouped first by chronological age then by fluid IQ, and Brinley plots of RT and RT difference scores (argued to give a purer measure of cognitive speed) were produced for each grouping. Two Brinley methods were compared: fixing the intercept of the line of best fit at the origin, and allowing it to vary. These produced quite different functions with correspondingly different implications for the speed theory. It is argued that previous findings of developmental speed increases (as measured by Brinley slope) may be an artifact of the fixed‐intercept method. When intercept was allowed to vary, findings indicated that speed did not change developmentally. Furthermore, when absolute RT and RT difference score findings were compared, partial correlations indicated that RT was related primarily to age rather than MA or IQ, whereas RT difference scores were related directly to IQ, but not to age or MA. We argue that the results are best accommodated by the theory that speed underlies stable IQ differences but not increases in MA. Instead, we argue that MA change may be better accounted for by children's increasing attentional ability.

The effects of aging on reaction time in a signal detection task.

The effects of aging on response time are examined in 2 simple signal detection tasks with young and older subjects (age 60 years and older). Older subjects were generally slower than young subjects, and standard Brinley plot analyses of response times showed typical results: slopes greater than 1 and (mostly) negative intercepts. R. Ratcliff, D. Spieler, and G. McKoon (2000) showed that the slopes of Brinley plots measure the relative standard deviations of the distributions of response times for older versus young subjects. Applying R. Ratcliff's (1978) diffusion model to fit the response times, their distributions, and response accuracy, it was found that the larger spread in older subjects' response times and their slowness relative to young subjects comes from a 50-ms slowing of the nondecision components of response time and more from conservative settings of response criteria.

Explicitly modeling the effects of aging on response time.

Research into the effects of aging on response time has focused on Brinley plots. Brinley plots are constructed by plotting mean response times for older subjects against those for young subjects for a set of experimental conditions. The typical result is a straight line with a slope greater than 1 and a negative intercept. This linear function has been interpreted as showing that aging leads to a general slowing of cognitive processes. In this article, we show that the slope of the Brinley plot is actually a measure of the relative standard deviations of older versus young subjects' response times; it is not a measure of general slowing. We examine current models of the effects of aging on mean response time and show how they might be reinterpreted. We also show how a more comprehensive model, Ratcliff's diffusion model (1978), can account for Brinley plot regularities and, at the same time, provide an account of accuracy rates, the shapes of response time distributions, and the relative speeds of error and correct response times, aspects of the data about which models designed to account for Brinley plots are mute. We conclude by endorsing a research approach that applies explicit models to response time data in aging in order to use the parameters of the model to interpret the effects of aging.

Effects of aging on voluntary and involuntary shifts of attention

This experiment examined adult age differences in the speed and accuracy of voluntary and involuntary shifts of visual attention. Younger and older adults performed two spatial cuing tasks using central cues and abrupt onset peripheral cues presented at stimulus onset asynchronies (SOAs) of 100, 150, 200, 250, and 300 ms. Analyses of the magnitudes of cuing effects revealed a similar time course for younger and older adults in the central cue condition, but not in the peripheral condition. Analyses of the Brinley plot for central cues across cue validity conditions indicated that as much as 93% of the variance could be attributed to age-related general slowing rather than to differential aging of a specific visual orienting mechanism.

Brinley plots, explained variance, and the analysis of age differences in response latencies.

Critics of Brinley plot analyses (e.g., Fisk, Fisher, & Rogers, 1992; Perfect, 1994) claim: (a) that lack of overlap between latencies on different tasks inflates r2 values; (b) that Brinley plots mask task-specific age differences; and (c) that measurement error in young adults' latencies precludes the use of regression techniques with Brinley plot data. We dispute these claims. We show that lack of overlap does not inflate r2 and that the possible presence of task-specific effects in Brinley plot data may be evaluated using standard regression techniques. These techniques are illustrated using data from the Fisk and Rogers (1991) study of visual and memory search. Analysis of their data reveals significant differences between the lexical and nonlexical domains, but not between types of search. Finally, the effect of measurement error on Brinley plot analyses is shown to be small and, if taken into account, leads to increased support for general cognitive slowing.

Brinley Plots and Theories of Aging: The Explicit, Muddled, and Implicit Debates

We evaluated the debates concerning Brinley plots and the associated theories of age-related slowing. We concluded that an explicit debate regarding a single-factor, general slowing model was no longer a debate as most, if not all, agree to the disconfirmation of that model. We address sources of confusion in the debates that have muddled the areas of genuine disagreement. When the confusion is lifted, the remaining debate centers, rightly, on evaluation of theories of aging. We show that Brinley plot analyses can lead to both falsely accepting and falsely rejecting theories of age-related slowing. Although plotting data most certainly can assist with the evaluation of cognitive theory, we argue that models of performance and learning must play a more central role in advancing theories of cognitive aging.

Generalized Slowing in Brinley Plots

The logic of generalized slowing theories is explored. Existing theories are reviewed briefly and put in a common format. The format is readily generalized to define a class of one-dimensional aging theories, a tiny subset of all possible aging theories. A corresponding class of compatible data is demonstrated, in terms of allowable configurations of a Brinley plot. Nonconforming configurations have the force of disconfirming the entire class of aging theories. Information processing theories can be cast in a similar format. It is shown that, for a slowing theory to be indisputably general, it must be associated with a multidimensional information processing theory.

The time it takes elderly and young individuals to draw pictures and write words.

Twenty elderly and 20 young Ss drew pictures or wrote words for picture or word stimuli. Elderly Ss had slower response initiation than young Ss, especially when drawing. Beyond this, both age groups processed picture and word stimuli similarly. Elderly and young Ss exhibited equivalent latency increases for cross-modality trials (e.g., draw a picture given a word) over within-modality trials (e.g., draw a picture given a picture), regardless of stimulus or task modality. Strong support was found for a mathematical model of these results, which assumes age-related additive slowing for input and output subprocesses but age invariance for a cross-modality transfer subprocess. However, regressing elderly on young whole-condition latencies indicated general, multiplicative slowing: a discrepancy that questions the utility of the global Brinley plot procedure in revealing the nature of age-related slowing.