Cognitive Function
RTI
The CANTAB testing
battery is a cognitive assessment system administered by touch screen.
Participants were introduced to the CANTAB tasks during an introductory
visit before the study commenced to minimize any learning effects.
The CANTAB battery was administered on each study day before and after
the commute and included four “tasks” focusing on different
cognitive domains and functional areas.The Attention Switching
Task (AST) indicates the costs of multitasking, showing cognitive
flexibility, and is indicative of executive function. For this test,
an arrow is shown pointing left or right and is displayed on the left
or right side of the screen. Participants are asked to indicate either
the side of the screen on which the arrow appears or its direction.
Sometimes, the arrow’s side and direction are incongruent,
whereas sometimes they agree. Longer reaction times for incongruent
stimuli are an indication of a Stroop effect (automatic processing
being faster than conscious visual control) or The Reaction Time (RTI) task measures
reaction and moving times
under simple and 5-choice scenarios. For this task, the subject holds
down a button until a spot is shown on the monitor, at which point
they move their finger to touch the spot with the same finger. The
spot can appear either in a single location (Simple) or in one of
five locations (5-choice).The
Rapid Visual Processing (RVP) task measures continuous performance
as well as visual sustained attention. For this task, 100 single digits
per minute appear in the center of a screen, and the subject must
indicate when they see specific number sequences by pressing a button.
The outcome measure The Spatial Working Memory
(SWM) task measures subjects’
capacity to retain and process spatial information. For this, subjects
search for blue squares by touching larger squares covering them,
without revisiting boxes where a blue square was previously uncovered. 