The purpose of this study was to compare working memory WM , executive function, academic ability, and problem classroom behaviors in children aged 8—11 years who were either identified via routine screening as having low WM, or had been diagnosed with ADHD. Standardized assessments of WM, executive function and reading and mathematics were administered to 83 children with ADHD, 50 children with low WM and 50 typically developing children. The ADHD and low WM groups had highly similar WM and executive function profiles, but were distinguished in two key respects: children with ADHD had higher levels of rated and observed impulsive behavior, and children with low WM had slower response times. Possible mechanisms for these common and distinct deficits are discussed. Deficits in working memory WM are common in childhood.
Search ADS. Wechsler abbreviated scale of intelligence. Standardized assessments of WM, executive function and reading and mathematics were administered to 83 children with ADHD, 50 children with low WM and 50 typically developing children. Harcourt Brace; New York: Learning and Individual Differences15 Working memory training in ADHD: controlling for engagement, motivation, and expectancy of improvement pilot study Journal of Attention Disorders. Where there were significant group differences, pairwise comparisons were conducted for each of the three pairwise group combinations. Marzocchi, G. The funders had no role in study Oboe peg, data collection and analysis, decision to publish, or preparation of the manuscript. Individual's latencies were determined at lateral occipital Why adults have low working memory for these components typical electrodes i.
Nast trannies. Falling short: deficits in working memory
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- I remember when I was a kid, I would sit in math class and take these detailed notes about how to do whatever type of math we were learning.
- Working memory, which is critical to executive functioning, is where you store short-term information you need to complete a task.
Many people are constrained by the limits of the working memory. Some are born with poor working memory; others acquire working memory problems through certain illnesses or natural aging and still others experience working memory problems because their environment places too many demands on their working memory.
Native deficits Many people experience poor working memory from a very young age and it affects their ability to focus attention, control impulses, stay organized and solve problems. Theresa Cerulli a prominent psychiatrist from Andover, Mass.
Acquired deficits Some people acquire working memory deficits after traumas such as stroke victims, pediatric cancer survivors and war veterans who have experienced traumatic brain injury. Many people — including very intelligent people — experience strains on their working memory because of external causes, namely the hectic environment in which they struggle to perform.
A growing list of research studies is shedding important light on why normally intelligent people fail under pressure and how the answer is centered on understanding working memory. In one example, Robert Rydell at the University of California, Santa Barbara and Allen McConnell at Miami University showed that a group of college women who normally perform well in math struggled significantly on a test when they were told they were competing against a group of men.
During post-experiment interviews, many women admitted they were nervous and distracted by the news they were being compared to men. The conclusion of this study, and many others like it, is that stress takes up working memory and leaves less capacity for the task at hand. Consumers Educators Health Care Professionals. About History The Cogmed Story. Falling short: deficits in working memory. Previous: A research breakthrough.
New York: Holt, Rinehart and Winston. Learn whether your short-term memory problems could be signs of a working memory deficit. For example, in WM tasks dependent on tracking items in a briefly-presented visual array, adults remember approximately 3 or 4 objects Cowan They said it was all due to my poor working memory. Five-year-olds recall only half as many Riggs et al J Clin Exp Neuropsychol.
Why adults have low working memory. Share Article Menu
The purpose of this study was to compare working memory WM , executive function, academic ability, and problem classroom behaviors in children aged 8—11 years who were either identified via routine screening as having low WM, or had been diagnosed with ADHD. Standardized assessments of WM, executive function and reading and mathematics were administered to 83 children with ADHD, 50 children with low WM and 50 typically developing children.
The ADHD and low WM groups had highly similar WM and executive function profiles, but were distinguished in two key respects: children with ADHD had higher levels of rated and observed impulsive behavior, and children with low WM had slower response times.
Possible mechanisms for these common and distinct deficits are discussed. Deficits in working memory WM are common in childhood. They are characteristic of children with specific learning difficulties in reading, mathematics, and language e. Poor WM during development has begun to be investigated in its own right rather than as a secondary symptom of another disorder, and has been found to be closely associated both with low academic achievement Gathercole and Alloway, ; Alloway et al.
This study provides the first direct comparison of cognitive skills, executive functions, learning and behavior between children with low WM and those of the same age diagnosed with ADHD. The outcomes have direct implications both for the diagnosis and treatment of the broad range of cognitive and behavioral problems found in these two groups and for the interplay between inattention and poor WM in childhood.
WM is comprised of distinct but interacting cognitive and neural systems that coordinate higher-level attentional control and the temporary storage of information, providing vital ongoing support for complex cognitive activities Baddeley, ; Unsworth and Engle, ; Cowan, There exist a variety of conceptualizations of the nature, structure, and function of WM see Conway et al. One important distinction between models is whether WM is conceived as a distinct multi-store workspace that includes an attentional component e.
In general, though, both frameworks provide adequate accounts of large bodies of empirical evidence e. Baddeley and Hitch's ; Baddeley, enduring multi-component model has provided a theoretical framework and set of methodologies that have been widely used for exploring WM in many cognitive developmental disorders including ADHD.
In this, a domain-general limited-capacity central executive system provides executive control of attention. There are many parallels between this subsystem and the controlled attention view of WM Kane et al. The central executive is part of a broader network of executive functions that includes inhibition, planning, and set switching and which relies on the same frontal brain networks to support flexible goal-directed behavior Duncan and Owen, ; Miyake et al.
Verbal and visuo-spatial short-term memory STM stores, and an integrative multi-modal episodic buffer, support the central executive Baddeley, Assessments of these different components of WM are distinguished by whether or not they impose significant processing demands. Whereas STM tasks require the storage of information, tasks tapping the executive component often termed complex span or WM tasks involve significant processing in addition to storage e.
These components have been suggested to contribute to many everyday cognitive activities including following instructions Yang et al. Children selected on the basis of low scores on measures of WM that tax both the central executive and STM stores, such as backward digit span or listening span, typically perform relatively poorly on school-based evaluations of curriculum learning e.
The majority have impairments in both reading and maths and in the classroom they frequently fail in activities that involve following instructions, storing information whilst engaged in other cognitively demanding activities, and place-keeping in complex tasks Gathercole et al.
Children with poor WM are also reported by teachers to be inattentive and have short attention spans Gathercole et al. Similarly, adults with low WM report high levels mind-wandering under conditions of high cognitive load Kane et al. Children with low WM also exhibit problems in other areas of executive function. They are rated by teachers as being relatively poor in areas relating to WM, the ability to monitor work, the inhibition of impulsive responses, and in planning and organization Gathercole et al.
On direct assessments of action planning and visual selective attention, they have also been reported to be impaired St Clair-Thompson, They too have impaired learning in reading and mathematics Loe and Feldman, , accompanied by WM difficulties Martinussen et al. The executive function problems in ADHD include response inhibition e. There is as yet no consensus regarding the origins of this complex profile of deficits.
Although the cognitive similarities between children with low WM and those with ADHD are striking, one marked difference is evident. Children with low WM do not exhibit excessive levels of motor activity and problems in impulse control that are core characteristics of ADHD Gathercole et al. One possibility is that the two groups share a common deficit in the cool executive function system that is associated with attentional difficulties but that only those with ADHD have impairments in the hot executive system linked with hyperactivity and impulsivity.
This hypothesis was investigated in the present study which, to our knowledge, is the first to compare directly the cognitive and behavioral characteristics of children who have poor WM but no ADHD diagnosis with those with ADHD. It was predicted that both groups would be impaired on direct measures of cool executive functions such as WM, planning and cognitive inhibitory control, and that they would be rated as being both inattentive and having elevated levels of other problem behaviors relating to these elements of high-level cognitive control.
The ADHD group were expected to be differentiated by further problems in impulse control, and both hyperactive and impulsive behavior; the same difficulties were not predicted for the low WM group.
Both direct assessments and teacher behavior ratings were obtained of a range of executive functions including WM and attentional control. Measures of IQ and learning were also included. Three groups of children participated in the study. One group consisted of 83 children 71 boys aged 8—11 years, with a clinical diagnosis of combined-type ADHD recruited through pediatric psychiatrists based in the North-East of England. All children had a clinical diagnosis of ADHD that included a psychosocial assessment, clinical and parent observer reports and a clinical assessment of the child's mental state.
Inclusion criteria for the present study were i a DSM 5 diagnosis of combined-type ADHD for 6 months or longer ii aged between 8 and 11 years iii no co-morbid Autistic Spectrum Disorders.
Fifteen children were not taking medication. Two further groups were recruited from a sample of children aged 8—11 years attending 10 state primary schools in the same region who were screened on two tests of verbal WM: Listening Recall and Backward Digit Recall from the Automated Working Memory Assessment AWMA; Alloway, Fifty children 30 boys with standard scores below 86 on both tests were assigned to a low WM group, and a further 50 children 27 boys with standard scores above 90 on both tests formed an age-typical WM group.
None of the children had a diagnosis of ADHD. Ethical approval was obtained through both the local National Health Service and Durham University's ethics boards. Testing took place on between two and five individual testing sessions according to the individual child, with a total testing time of approximately 4 h. Regular breaks were introduced as required to reduce fatigue and optimize compliance. All assessments were conducted in a quiet area of the child's school. Children with ADHD receiving drug treatment ceased ingestion at least 24 h prior to testing.
As all prescribed drugs were fast release, their physiological effects were eliminated at the time of test. Both children and their teachers were asked to verify that no medication had been taken prior to testing. All children in the comparison group completed every task. All tests yield standard scores. The higher-level executive condition, Number-Letter Sequencing, requires children to connect letters and numbers in a progressive increasing alternating sequence ABC-3 , etc.
Completion times are calculated for each condition and converted to scaled scores. Errors are represented as cumulative percentiles for baseline conditions and as a scaled score for the switching measure. A scaled contrast score represents differences in performance between the baseline and switching measure.
Inhibition and inhibition with switching. The Color Word Interference condition involves a standard Stroop task in which the child inhibits the over-learned verbal response of naming a color word, and instead names the ink color. The Color Word with Switch condition involves two executive functions: inhibition and switching. The child is instructed to name the color of the ink for all words except those displayed in a box; on these trials, the task is to name the color word rather than the ink color.
Further baseline conditions, Color Word Reading and Color Naming, assessed relevant processing abilities. Completion times are converted to scaled scores for all tasks. Errors are scored as cumulative percentiles for baseline tasks and scaled scores for the executive tasks.
In one condition, Free Sort, the child sorted the cards into as many categories as possible. Both the number of correct sorts and level of the description of each sort were scored. In a second condition, Recognition, the examiner sorted the cards into different categories and asked the child to describe what principles had been used to sort the cards.
Both the number of correct sorts and the descriptions of the sorts were converted to scaled scores. Total achievement and time per move scores are converted to scaled scores. Total rule violations are scored as cumulative percentiles. Sustained attention. In this task, a series of letters appear on the computer screen at a rate of 1 per second.
The child's task is to press the space bar only when a K is displayed, which occurs on of the trials at random intervals. The following measures are obtained: average response delay in ms, the numbers of omissions possible range 0— and commissions possible range 0— , and total accuracy proportion of trials correct. Response suppression. Correct responses are converted to a scaled scores. Reading and mathematics. The basic reading, spelling and reading comprehension subtests of the Wechsler Objective Reading Dimensions Wechsler, , and both subtests of the Wechsler Objective Number Dimensions Wechsler, , mathematical reasoning and number operations, were administered.
In each case, standard scores were calculated. Verbal and Performance IQ standard scores were calculated from subtest scores. Teacher rating scale. Teachers rate 28 statements as not true at all 0 , just a little true 1 , pretty much true 2 or very much true 3. These statements comprise four subscales, which provide an index of oppositional behavior, cognitive problems and inattention, hyperactivity and ADHD symptoms.
T -scores were calculated. Behavior rating inventory of executive function. T -scores were calculated for each scale and composite index. Descriptive statistics for the cognitive measures are displayed by group in Table 1 and behavior ratings are shown in Table 2. Separate multivariate analyses of variance MANOVA were conducted for those tests that generated multiple dependent variables on a comparable scale: WM, IQ, reading, mathematics, and teacher behavior ratings.
Univariate F -tests compared performance between groups on individual measures. Where there were significant group differences, pairwise comparisons were conducted for each of the three pairwise group combinations. Univariate F -tests revealed significant group effects for all of the individual STM and WM subtests and the four derived composite scores. Univariate analyses established significant group differences in two of the baseline tasks; Number Sequencing completion times and Letter Sequencing errors.
There were no significant group differences in the other baseline conditions, Motor Speed and Visual Scanning. There were significant group differences in the frequency of errors on the higher-level switching task, Number-Letter Sequencing. However, the group difference in contrast scores, which reflect differences in performance between the baseline and higher-level conditions, was not significant.
The ADHD group were also significantly less accurate than the comparison group in the baseline Letter Sequencing condition.