Nicotinic Enhancement of Cognitive Remediation Training in Schizophrenia

The MCCB is an FDA-approved assessment tool for trials of cognition-enhancing treatments in people with schizophrenia. The MCCB is comprised of the following domains: 1) Speed of Processing; 2) Attention/Vigilance; 3) Working Memory; 4) Verbal Learning; 5) Visual Learning; 6) Reasoning and Problem Solving; and 7) Social Cognition. The composite score is standardized to a T-scale (mean=50, standard deviation=10) based on healthy control normative data. Better performance is reflected by higher scores.

Clinician-administered interview about daily life cognitive functioning. The CAI assesses 10 items related to working memory, attention/vigilance, learning/memory, problem solving, processing speed, and social cognition. The total score ranges from 1 (inability to maintain personal hygiene due to cognitive deficits) to 100 (superior cognitive functioning in a wide range of activities). A score of 55 corresponds to moderate cognitive symptoms, e.g. persistent problems paying attention or forgetting scheduled events.

Semi-structured clinician interview measuring functional outcome and quality of life in people with schizophrenia. Includes subjective questions regarding life satisfaction and objective indicators of social and occupational role functioning during preceding 4 weeks. Seven items are scored on a 0 (severe impairment) to 6 (high functioning) scale. The total score ranges from 0 to 42, with larger values reflecting higher functioning.

Measures ability to perform real-life tasks by standardized role-play. Scores reflect percent correct, i.e. range from 0-100 with higher scores representing better performance.

Clinician scale developed to assess the level of depression in schizophrenia. 9 items assess symptoms of depression and overall rater impression on a scale from 0 (absent) to 3 (severe).

Clinician rating scale of negative symptoms in schizophrenia. Within each of 5 domains, separate symptoms are rated from 0 (absent) to 5 (severe). Total scores are the sum of 22 subscales and range from 0 to 110, with larger values reflecting higher negative symptoms.

Clinician rating scale to measure psychotic symptoms. Each of 20 items is scored 1-7. Total scores are the sum of all items and range from 20 to 140, with larger values reflecting worse symptoms.

Some of the Posit Science exercises provide an assessment tool of training progress on task parameters, which adjust continuously to keep performance at ~85% correct. Enhanced sensory processing speed and precision is considered the central building block of training benefits. Therefore, we analyzed the two exercises aimed at training these processes. Performance is quantified as stimulus presentation time in ms of visual or sound "sweeps", which the participant has to judge in terms of change across space or time. Smaller values reflect better performance. Visual and sound sweeps were averaged.

Derived from a computerized change localization task. One to four colored squares are shown for 100 ms. After a delay, they reappear and the task is to click on the one square that has changed color (50% chance). Performance is expressed as the percentage of correct responses.