The LA5C was a nested study within LA2K, furthering the work to include patients. The assessed population included 200 healthy controls recruited from LA2K, 100 schizophrenia patients, 100 bipolar patients, and 100 ADHD patients.
See here for the LA2K manual: LA2k_manual.
The participants, ages 21-50, were recruited by community advertisements from the Los Angeles area and completed extensive neuropsychogical testing, in addition to fMRI scanning. To be included individuals had to be either “White, Not of Hispanic or Latino Origin” or “Hispanic or Latino, of Any Race” following NIH designations of racial and ethnic minority groups, and have completed at least 8 years of education (other racial and ethnic minority groups were excluded because this was thought to increase risk of confounding planned genetic studies). For participants who spoke both English and Spanish, language for testing was determined by a verbal fluency test. Participants were screened for neurological disease, history of head injury with loss of consciousness or cognitive sequelae, use of psychoactive medications, substance dependence within past 6 months, history of major mental illness or ADHD, and current mood or anxiety disorder. Self-reported history of psychopathology was verified with the SCID-IV (First, Spitzer, Gibbon, & Williams, 1995). Urinalysis was used to screen for drugs of abuse (cannabis, amphetamine, opioids, cocaine, benzodiazepines) on the day of testing and excluded if results were positive.
A portion of this large sample took part in two separate fMRI sessions, which each included one-hour of behavioral testing and a one-hour scan on the same day. Participants were recruited from the parent study to participate in the fMRI portion if they successfully completed all previous testing sessions, and did not meet the following additional exclusion criteria: history of significant medical illness, contraindications for MRI (including pregnancy), any mood-altering medication on scan day (based on self-report), vision that was insufficient to see task stimuli, and left-handedness.
After receiving a thorough explanation, all participants gave written informed consent according to the procedures approved by the University of California Los Angeles Institutional Review Board.
For more information on the LA5C please contact:
Eliza Congdon, Ph.D. email email@example.com
Katie Karlsgodt, Ph.D. email firstname.lastname@example.org
Russell Poldrack, Ph.D. email email@example.com
Fred Sabb, Ph.D. email firstname.lastname@example.org
Full documentation of study procedures can be found in the LA5C Manual. For parameters of individual scans or further information on specific tasks, please see pages below.
Overall Study Design
Subjects participated in two scans ("A" and "B") in a counterbalanced fashion.
Scan A included: localizer, MPRAGE, DTI, Matched Bandwidth Hires, BART, PAM encoding and PAM retrieval.
Scan B included: localizer, Matched Bandwidth Hires, Resting State, Breath Hold Task, StopSignal, SCAP, and Taskswitching
Identification numbers were assigned in the order of recruitment. Healthy controls have ID numbers starting with 1 (CNP_11156). Patients with schizophrenia have ID's starting with 5 (CNP_50004), patients with Bipolar Disorder start with 6, and patients with ADHD start with 7. A and B scans were designated by appending an A or B to the ID- CNP_11156A and CNP_11156B are the two scans for the same individual.
Subjects scanned at two different facilities, each with a Siemens Trio, using the same sequences. Quality control measures were in place before deciding to switch to the CCN scanner, however, as always, there are small differences. Therefore, which scanner was used must be accounted for in all analyses.
Preprocessing and Quality Control
Requesting and Analyzing Data
Link back to HTAC page.