Neurobehavioral Assessments of Cerebral Vasospasm - Animal Models of Acute Neurological Injuries: Injury and Mechanistic Assessments - page 557

measures for this test. Trials are scored as successes or failures.
Successful trials are scored when the animal correctly nose pokes
into the illuminated aperture.
Assessed behaviors include several aspects of attention, vigilance,
executive control, and self-regulation (mice ( 92, 108, 126 ); rats
( 52, 154-156 ); rats and mice ( 157 ); and monkeys ( 158 )).

6.14.2. Attention
Set Shifting Test
and Reversal Learning

The Attention Set Shifting Test (AST) represents the animal version
of a diagnostic test used on humans in the clinic, the Wisconsin
Card Sorting Test (WCST), and has been used on rats, mice, and
monkeys.
Rodents are trained to dig in bowls for a food reward on a
series of three simple discriminations (cues), e.g., texture, odor,
and digging medium. Two bowls are presented in each trial, only
one of which is baited. For the simple discrimination, the trained
animal has to select the bowl in which to dig by salient cue (i.e.,
texture, odor, and digging medium). After the tested animal learns
to associate a cue with a reward, the rules are changed or reversed
and the animal has to learn a new association. For compound dis-
crimination, new stimuli and cues are presented in pairs. Other
distracting dimensions may be introduced to make the test more
challenging.
For monkeys, AST can be conducted using touch-screen
computer-based CANTAB and WGTA methodology. The num-
ber of trials required to master each type of discrimination is used
as a measure for AST. Perceptual attention, problem solving, eti-
ologic factors, and mechanisms involved in treating depression
and anxiety are the behaviors that can be assessed with AST (rats
( 156, 159, 160 ); mice ( 161-163 ); and monkeys ( 164-167 )).

Rats and monkeys have been used in Go-Trial Reaction Time
(GoRT)/Stop-Signal Reaction time (SSRT) tests. In an operant
conditioning chamber with right and left levers and a pellet dis-
penser, a rat is trained to press fi rst the left lever, and then the right
lever to receive a food reward (GoRT). For SSRT trials, the short
sound may be periodically introduced between pressing left and
right levers and the rat is food rewarded if it does not press the
right lever if it hears the sound.
Monkeys have been trained to either lift or not lift the lever for
a reward in response to auditory stimuli of various intensities and
duration or visual stimuli of various colors ( 168 ). Additionally, mon-
keys have been trained to make or suppress saccade eye movements for
a reward in response to a peripheral visual stimulus depending on the
location of the stimulus and presence or absence of a delay ( 169, 170 ).
Measures for GoRT/SSRT test are percent of expected outcomes
and speed of the response to stop the process. GoRT/SSRT are used
to assess attention dysfunction, behavioral inhibition, and problem
solving (rats ( 156, 166 ) and monkeys ( 168-170 )).

6.14.3. Go-Trial Reaction
Time Task and Stop-Signal
Reaction Time Task
(“Go-No-Go” Tasks)