Clinical trial NCT01657721: Working Memory Training in ADHD (The Engage Study)
Official title: Working Memory Training in Attention-Deficit/Hyperactivity Disorder: Neural Mechanisms of Change
Study type: INTERVENTIONAL
Overall status: UNKNOWN
Phase: PHASE1
Conditions: Attention-Deficit Hyperactivity Disorder
Lead sponsor: University of Toronto
Sponsor class: OTHER
First posted: 2012-08-06
Enrollment: 160
Sex: ALL
Minimum age (years): 18
Maximum age (years): 35
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: TREATMENT

Brief summary: The overall objective of the current study is to determine whether computerized Working Memory (WM) training will enhance WM capacity in college students with Attention Deficit Hyperactivity Disorder (ADHD). There are also four additional objectives. The first is to investigate whether the program's efficacy is impacted by the duration of the daily training sessions. The second is to determine whether improvements in WM will generalize to secondary outcome tasks, such as inhibitory control and planning. The third objective is to examine whether WM training will also ameliorate ADHD symptoms of inattention and hyperactivity. The last objective is to investigate whether improvements will be maintained at a two month follow-up period. The investigators will also be assessing healthy control participants,who will not be receiving treatment, but will be used as a basis of comparison with the ADHD participants,

It is expected that the computerized WM training program will enhance WM capacity in college students with ADHD. In addition, it is believed that these increases in WM capacity will also lead to improvements in other executive functions. It is also hypothesized that WM training will lead to a reduction in ADHD symptomology. Lastly, these improvements should be maintained at three month follow-up.

Detailed description: Attention-Deficit/Hyperactivity Disorder (ADHD) and Learning Disability (LD) are among the most common neurobehavioural disorders, with prevalence rates estimated at about 5% to 9% . Approximately 4% of youth in the United States have a comorbid diagnosis of ADHD and a Learning Disability (ADHD/LD). Research has shown ADHD/LD symptoms persist into young adulthood, a time when many are enrolled in post-secondary education. Students with ADHD/LD at the post-secondary education level constitute an emergent subgroup of the ADHD and LD populations that have received far less attention in the literature compared to children, adolescents and employed adults. The actual percentage of college students with ADHD/LD is unknown; however, some estimates suggest that 2-8% of students attending post secondary education have ADHD, LD or both. Youth with the additive problems of both disorders are at high risk for academic failure, and poor psychosocial and occupational outcomes in adulthood. The "multiple deficit model" suggests that there is a common genetic and neuropsychological underpinning to these disorders. For example, ADHD and LD share similar features, such as core deficits in processing speed and working memory. ADHD and LD are each associated with several cognitive difficulties including poor working memory (WM) and processing speed. WM is a "mental workspace" that provides temporary storage and manipulation of information and is closely related to g, a proposed measure of general cognitive ability. In addition, WM has also been found to predict academic achievement. One major problem is that current intervention approaches for ADHD/LD do not target the underlying cognitive deficits fundamental to these diagnoses. Thus, interventions that address underlying cognitive difficulties, such as WM, are a promising avenue of additional treatment for youth with combined ADHD/LD.

WM capacity has generally been thought to be a fixed trait, but recent studies have suggested that it can be improved by intensive and adaptive computerized training. This intervention approach has been evaluated in children and adolescents with ADHD, older adults, and adult stroke patients and shown promising results. Subjects not only improved on the trained WM tasks, but some of the studies suggest that improvements may generalize to non-trained WM activities, complex reasoning tasks, academic functioning, and behavioral symptoms of ADHD or working memory failure. Moreover, brain imaging studies have provided converging evidence of training-related improvements in working memory: specifically increased activation has been found in cortical regions implicated in working memory. However, no studies to date have investigated whether WM capacity can be improved in a population of young adults with ADHD/LD enrolled in post-secondary education programs. Nor have the results been replicated or elaborated upon using different imaging methodologies, like EEG (Electroencephalography), which is able to capture the millisecond time parameters of cognitive processing and so may provide new insights into the neural mechanism of WM and effects of WM training.

The overall objective of the current study is to determine the effectiveness of WM training, as administered by community-based psychologists licensed to provide this training, for college students with ADHD/LD. Specific objectives are to determine whether; i) standard-length computerized WM training enhances WM capacity in college students with ADHD/LD, using behavioral as well as neuro-imaging indices of change; ii) shortened-length WM training would also result in improvements in WM; iii) WM training normalizes WM performance, as compared to typically developing peers (i.e., a healthy comparison group of college students); iv) improvements in WM will generalize to secondary outcome tasks, such as inhibitory control and planning; v) WM training will also ameliorate ADHD symptoms of inattention and hyperactivity; and vi) improvements will be sustained for at least a few months after completing the training.

Eligibility criteria: Inclusion Criteria:

* Formal diagnosis of ADHD by a doctor or psychologist
* Registered as a student at a post-secondary institution
* Registered with Student Disability/Accessibility Services at post-secondary institution

Exclusion Criteria:

* Major neurological dysfunction and psychosis
* Current use of sedating or mood altering medication other than stimulants provided for ADHD
* Motor or perceptual handicap that would prevent using the computer program.

Primary outcomes:
measure: Wechsler Adult Intelligence Scale: Digit Span subtest
timeFrame: within 120 days
Secondary outcomes:
measure: Adult ADHD Self-Report Scale (ASRS v1.1)
timeFrame: within 120 days
measure: 'Add-3' working memory test
timeFrame: within 120 days
measure: Cambridge Neuropsychological Testing Automated Battery: Spatial Span Task
timeFrame: within 120 days
measure: Wide Range Assessment of Memory and Learning: Finger-Windows subtest
timeFrame: within 120 days
measure: Barkley Deficits in Executive Functioning Scale (BDEFS)
timeFrame: within 120 days
measure: Cognitive Failures Questionnaire
timeFrame: within 120 days
measure: Go-nogo task (N200, P300)
timeFrame: within 120 days
measure: Delayed Working Memory Task (P300)
timeFrame: within 120 days
measure: Selective Working Memory Task (CDA)
timeFrame: within 120 days
Other outcomes:
Locations:
city: Toronto
country: Canada
facility: Ontario Institute of Studies in Education (OISE) at The University of Toronto
state: Ontario
Study officials:
affiliation: University of Toronto
name: Rosemary Tannock, Ph.D.
role: PRINCIPAL_INVESTIGATOR
References:
citation: Liu ZX, Glizer D, Tannock R, Woltering S. EEG alpha power during maintenance of information in working memory in adults with ADHD and its plasticity due to working memory training: A randomized controlled trial. Clin Neurophysiol. 2016 Feb;127(2):1307-1320. doi: 10.1016/j.clinph.2015.10.032. Epub 2015 Oct 20.
citation: Mawjee K, Woltering S, Tannock R. Working Memory Training in Post-Secondary Students with ADHD: A Randomized Controlled Study. PLoS One. 2015 Sep 23;10(9):e0137173. doi: 10.1371/journal.pone.0137173. eCollection 2015.