Target ADHD Executive Working Memory Replication Study

fMRI measures of brain activation and functional connectivity - Conventional measures of 'brain activation' are estimated using GLM regression models that fit the fMRI BOLD timeseries data to a model of expected hemodynamic change as elicited by fMRI versions of the executive working memory training task trials. Functional connectivity is assessed using a form of cross-correlation analysis that quantifies how much the entire BOLD timeseries in different brain regions are similar to one another. Our a priori treatment target brain regions are the superior frontal sulcus and mid-lateral prefrontal cortex region of interest. Brain activity and functional connectivity specifically to these regions represent the primary outcome measures of the study.

Reaction time (RT) from training tasks of executive working memory. These are experimental, non-published tasks that were tested in this project for the first time in Phase I: Updating (removal then replacement of stimuli by new information to be maintained in working memory), Shifting (refocusing selective attention on different stimuli held concurrent in working memory without altering contents), distractor Filtering (inhibiting irrelevant information) and Suppression (resolution of proactive interference from initial stimuli to be able to respond optimally to control trials). Trial structure and duration are similar across these tasks. The tasks record RT in milliseconds. Data from active experimental conditions will be log-transformed prior to statistical testing.

Accuracy (defined as percentage of correct answers from the pool of available items) from training tasks of executive working memory. These are experimental, non-published tasks that were tested in this project for the first time in Phase I: Updating (removal then replacement of stimuli by new information to be maintained in working memory), Shifting (refocusing selective attention on different stimuli held concurrent in working memory without altering contents), distractor Filtering (inhibiting irrelevant information) and Suppression (resolution of proactive interference from initial stimuli to be able to respond optimally to control trials). Trial structure and duration are similar across these tasks. Data from active experimental conditions will be arcsine-transformed prior to statistical testing.

The parent and self-report short forms of the Conners' Rating Scales were designed for repeated and/or brief assessment of symptoms relevant to ADHD and related disorders.

Items are measured on a likert scale from 0-3. There are 39 items with total raw scores ranging from 0-117. Higher scores indicate greater severity in ADHD sympotms. This instrument will be used as confirmation of significant association between symptom severity and evidence of target engagement in brain regions.

The Near/Far transfer tasks are computer tasks designed by the Principal Investigator to detail common Working Memory processes. They are programmed and adminstered utilizing E-Prime software. The Near Transfer tasks will test the generalizability of Executive Working Memory training outside of trained tasks, and the Far Transfer tasks will test the training effects to other abilities often impaired in ADHD. They are comprised of four categories: Shifting - Refresh/Repeat Task, Updating - Spatial Updating Task, Filtering - Attend-Ignore Task, and Suppression - Introducing Resistance Task