|
|
|
|
 |
| CANTAB - Executive function, working memory and planning tests |
|
 |
To
view all CANTAB tests, click here [open/close]
|
| These tests address executive function, working memory, and planning; all associated with the frontal area of the brain. |
|
Intra-Extra
Dimensional Set Shift (IED)
|
Overview
Intra-Extra Dimensional Set Shift is a test of rule
acquisition and reversal. It features:
- visual discrimination and attentional set
formation
- maintenance, shifting and flexibility of attention
This test is primarily sensitive to changes to
the fronto-striatal areas of the brain.
This test is a computerised analogue of the Wisconsin
Card Sorting test, and is sensitive to cognitive
changes associated with schizophrenia, Parkinson's
Disease, and dopaminergic dependent processes.
|
 |
Administration time
Around 7 minutes, depending on level of impairment.
Task
Two artificial dimensions are used in the test:
- colour-filled shapes
- white lines
Simple stimuli are made up of just one of these
dimensions, whereas compound stimuli are made
up of both, namely white lines overlying colour-filled
shapes. The subject starts by seeing two simple
colour-filled shapes, and must learn which one
is correct by touching it.
Feedback teaches the subject which stimulus is
correct, and after six correct responses, the
stimuli and/or rules are changed. These shifts
are initially intra-dimensional (e.g. colour filled
shapes remain the only relevant dimension), then
later extra-dimensional (white lines become the
only relevant dimension).
Subjects progress through the test by satisfying
a set criterion of learning at each stage (6 consecutive
correct responses). If at any stage the subject
fails to reach this criterion after 50 trials,
the test terminates.
Test modes
Clinical mode (for testing once); seven parallel
modes (for repeated testing).
|
Outcome measures
This test has eighteen outcome measures, assessing
errors, and numbers of trials and stages completed. |
|
One Touch
Stockings of Cambridge (OTS)
|
Overview
One Touch Stockings of Cambridge is a spatial planning
test which gives a measure of frontal lobe function.
OTS is a variant of the Stockings
of Cambridge test (see below) and places greater
demands on working memory as the subject has to
visualise the solution |
click
for an interactive demonstration |
Administration time
Around 10 minutes, depending on level of impairment
Task
As for SOC (Stockings of Cambridge), the subject
is shown two displays containing three coloured
balls. The displays are presented in such a way
that they can easily be perceived as stacks of
coloured balls held in stockings or socks suspended
from a beam. This arrangement makes the 3-D concepts
involved apparent to the subject, and fits with
the verbal instructions.
There is a row of numbered boxes along the bottom
of the screen. The test administrator first demonstrates
to the subject how to use the balls in the lower
display to copy the pattern in the upper display,
and completes one demonstration problem, where
the solution requires one move. The subject must
then complete three further problems, one each
of 2 moves, 3 moves and 4 moves.
Next the subject is shown further problems, and
must work out in their head how many moves the
solutions to these problems require, then touch
the appropriate box at the bottom of the screen
to indicate their response.
Test modes
OTS has four modes, with varying numbers of problems
and boxes.
|
Outcome measures
OTS has 4 outcome measures - problems solved on
first choice, mean choices to correct, mean latency
to first choice and mean latency to correct. Each
of these measures may be calculated for all problems,
or for problems with a specified number of moves
(1-move to 5 or 6 moves). |
|
Stockings
of Cambridge (SOC)
|
Overview
SOC is a spatial planning test which gives a measure
of frontal lobe function.
|
|
|
Administration time
Around 10 minutes, depending on level of impairment
Task
The subject is shown two displays containing three
coloured balls. The displays are presented in
such a way that they can easily be perceived as
stacks of coloured balls held in stockings or
socks suspended from a beam. This arrangement
makes the 3-D concepts involved apparent to the
subject, and fits with the verbal instructions.
The subject must use the balls in the lower display
to copy the pattern shown in the upper display.
The balls may be moved one at a time by touching
the required ball, then touching the position
to which it should be moved. The time taken to
complete the pattern and the number of moves required
are taken as measures of the subject’s planning
ability.
Test modes
Clinical mode
|
Outcome measures
This test has three outcome measures, including
the number and percentage of correct trials and
latency (speed of subject’s response). |
|
Spatial
Span (SSP)
|
Overview
Spatial Span assesses working memory capacity, and
is a visuospatial analogue of the Digit Span test.
|
|
|
Administration time
Around 5 minutes, depending on level of impairment
Task
White squares are shown, some of which briefly
change colour in a variable sequence. The subject
must then touch the boxes which changed colour
in the same order that they were displayed by
the computer (for clinical mode) or in the reverse
order (for reverse mode). The number of boxes
increases from 2 at the start of the test to 9
at the end, and the sequence and colour are varied
through the test.
Test modes
Two modes: clinical mode and reverse mode.
|
Outcome measures
This test has six outcome measures, covering span
length (the longest sequence successfully recalled),
errors, number of attempts and latency. |
|
Spatial
Working Memory (SWM)
|
Overview
SWM is a test of the subject’s ability to retain
spatial information and to manipulate remembered
items in working memory. It is a self-ordered task,
which also assesses heuristic strategy. This test
is a sensitive measure of frontal lobe and ‘executive’
dysfunction. It has been shown in recent studies
that impaired performance on SWM emerges as a common
factor in prepsychosis. |
|
|
Administration time
Around 8 minutes, depending on level of impairment
Task
The test begins with a number of coloured squares
(boxes) being shown on the screen. The aim of
this test is that, by touching the boxes and using
a process of elimination, the subject should find
one blue ‘token’ in each of a number
of boxes and use them to fill up an empty column
on the right hand side of the screen. The number
of boxes is gradually increased, until it is necessary
to search a total of eight boxes. The colour and
position of the boxes used are changed from trial
to trial to discourage the use of stereotyped
search strategies.
Test modes
Clinical mode.
|
Outcome measures
The twenty-four outcome measures for SWM include
errors (touching boxes that have been found to be
empty, and revisiting boxes which have already been
found to contain a token), a measure of strategy,
and latency measures. |
|
|
 |
|
| |
|
