 |
Previous Article | Next Article 
The Journal of Neuroscience, October 15, 2000, 20(20):7816-7821
Stress-Level Cortisol Treatment Impairs Inhibitory Control of
Behavior in Monkeys
David M.
Lyons,
Jacqueline M.
Lopez,
Chou
Yang, and
Alan F.
Schatzberg
Department of Psychiatry and Behavioral Science, Stanford
University School of Medicine, Stanford, California 94305-5485
 |
ABSTRACT |
Most studies of cortisol-induced cognitive impairments have focused
on hippocampal-dependent memory. This study investigates a different
aspect of cognition in a randomized placebo-controlled experiment with
monkeys that were treated with cortisol according to a protocol that
simulates a prolonged stress response. Young adult and older adult
monkeys were assigned randomly to placebo or chronic treatment with
cortisol in a 2 × 2 factorial design (n = 8 monkeys per condition). Inhibitory control of behavior was assessed
with a test shown previously in primates to reflect prefrontal cortical
dysfunction. Failure to inhibit a specific goal-directed response was
evident more often in older adults. Treatment with cortisol increased
this propensity in both older and young adult monkeys. Age-related
differences in response inhibition were consistent across blocks of
repeated test trials, but the treatment effects were clearly expressed
only after prolonged exposure to cortisol. Aspects of performance that
did not require inhibition were not altered by age or treatment with
cortisol, which concurs with effects on response inhibition rather than nonspecific changes in behavior. These findings lend support to related
reports that cortisol-induced disruptions in prefrontal dopamine
neurotransmission may contribute to deficits in response inhibition and
play a role in cognitive impairments associated with endogenous
hypercortisolism in humans.
Key words:
glucocorticoids; dopamine; prefrontal cortex; stress; aging; manual laterality; cognition; response inhibition
 |
INTRODUCTION |
Research on cortisol-induced
cognitive impairments has focused primarily on the hippocampus where
cortisol binds with different affinities to mineralocorticoid and
glucocorticoid receptors (McEwen and Sapolsky, 1995 ; de Kloet et al.,
1999 ; Newcomer et al., 1999 ). Here we address a different aspect of
cognition using a test shown previously in primates to reflect
prefrontal cortical dysfunction (Diamond, 1990 ; Taylor et al., 1990c ;
Dias et al., 1996 ; Jentsch et al., 1999 ). A clear Plexiglas box with
one open side is baited with a favorite food treat. When the box
opening is oriented straight toward the test subject, food retrieval is
achieved by line-of-sight reaching into the center of the box. When the
box is rotated 90° so the opening is oriented toward either side,
inhibition of line-of-sight reaching is required to retrieve food from
the clear baited box. Reaches aimed straight toward the center of the
box when the opening is oriented toward either side are scored as
line-of-sight response inhibition errors, which seldom occur when tests
are conducted with a baited opaque Plexiglas box (Diamond, 1990 ; Taylor
et al., 1990c ).
Inhibitory control of the line-of-sight response improves gradually
with frontal lobe maturation in primates tested with a baited clear box
(Diamond, 1990 ). In addition to line-of-sight response inhibition
errors, awkward retrievals with the hand contralateral to the box
opening are common in human infants and infant monkeys (Diamond, 1990 ).
Deficits expressed early in development are reproduced in marmosets and
rhesus monkeys by structural lesions in the adult prefrontal cortex
(Diamond et al., 1989 ; Diamond, 1990 ; Dias et al., 1996 ). Identical
line-of-sight response inhibition deficits are produced in adult vervet
monkeys by treatment with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) (Taylor et al., 1990a ,b ,c ), a neurotoxin that depletes dopamine
in the substantia nigra and frontostriatal circuitry (Di Paolo et al.,
1986 ; Elsworth et al., 1987 ; Slovin et al., 1999 ). Impaired inhibition
of line-of-sight reaching is also produced in adult vervet monkeys
treated repeatedly with phencyclidine, which selectively decreases
dopamine use in the prefrontal cortex (Jentsch et al., 1997 , 1999 ).
Inhibitory control of behavior is restored by clozapine-induced
increases in prefrontal dopamine use in monkeys treated previously with
phencyclidine (Jentsch et al., 1997 ). That diminished dopamine use
mirrors the effect of direct structural damage to the prefrontal cortex
is consistent with studies of spatial delayed working memory but not
other prefrontal-dependent tasks (Brozoski et al., 1979 ; Roberts et
al., 1994 ; Collins et al., 1998 ).
Cortisol-induced changes in response inhibition are examined in this
study of young and older adult squirrel monkeys tested on the
line-of-sight reaching response task with a baited clear Plexiglas box.
All monkeys were trained for 10 consecutive days with the box opening
oriented straight to reinforce the line-of-sight reaching response. The
orientation of the box was then varied systematically with
straight-facing trials interspersed among trials conducted with the box
opening oriented toward either side.
 |
MATERIALS AND METHODS |
A total of 32 female squirrel monkeys (Saimiri
sciureus) of Guyanese origin that were born and raised at the
Stanford University Primate Facility served as subjects. Sixteen
monkeys were young adults with a median age of 3 years (range, 27-44
months). The other 16 monkeys were older adults with a median age of 12 years (range, 116-171 months). Squirrel monkeys achieve sexual
maturity at 2.5-3.5 years, and their life span is ~21 years (Brady,
2000 ).
Monkeys were housed and tested individually in wire-mesh cages (60 × 60 × 90 cm) that allowed visual, auditory, olfactory, and
limited tactile contact between adjacent animals. Cages were located in
a climate-controlled room on a 12:12 hr light/dark cycle. All
procedures were conducted in accordance with and as required by the
Animal Welfare Act and approved by Stanford University's Administrative Panel on Laboratory Animal Care.
Training and test procedures. The apparatus used for
training and testing was a clear Plexiglas box (8 × 8 × 8 cm) with one open side baited with a marshmallow treat. The box was
locked into place on a 12 × 50 cm horizontal tray secured to a
tripod placed in front of each monkey's cage. Initially, all monkeys were administered 10 training trials per day for 10 consecutive days
with the box opening always oriented straight. Thereafter, monkeys were
administered 10 test trials per day for 21 consecutive days with the
orientation of the box opening varied systematically (Fig.
1). On each day of testing, the box
opening was oriented straight on the 1st, 4th, 7th, and 10th
trials. For the 2nd, 5th, and 8th daily trials, the box was rotated
90° so the opening was oriented toward the left. For the 3rd, 6th,
and 9th daily trials, the box was rotated 90° so the opening was
oriented toward the right.
Each trial lasted 30 sec or was terminated as soon as the marshmallow
was retrieved. During the ensuing 30 sec intertrial interval, the
experimenter removed the box from the tray, rebaited the box for the
subsequent trial, and recorded the direction of each reach attempt and
the hand used on successful retrievals. After completion of the daily
test trials, monkeys were fed unrestricted amounts of commercial monkey
chow with fresh fruit supplements. The following morning 4 hr before
testing, all uneaten food was removed. Each monkey was tested at the
same time of day between 14:00 and 17:00 hr.
Treatment conditions. Eight young and 8 older adult monkeys
were assigned randomly to each of two treatment conditions in a 2 × 2 factorial design. In one condition, cortisol hemisuccinate (Steraloids, Newport, RI) was dissolved in water (420 mg/l) flavored with red cherry juice and provided to the monkeys as their sole source
of water in standard drinking bottles. In the placebo condition, monkeys were provisioned in an identical manner with red-dyed drinking
water. Placebo and cortisol treatment conditions were initiated 7 d before the 21 d test phase of the study and were maintained
continuously for the duration of the experiment. In a pilot study we
determined that amounts of cortisol consumed by the use of this
protocol result in plasma levels of cortisol and adrenocorticotropic
hormone (ACTH) that approximate a previously described chronic stress
response (Lyons et al., 1995 , 1999 ). Because drinking water is consumed
during active daylight hours, this mode of administration preserves
normal circadian rhythms and eliminates the need for repeated
injections that can disrupt performance on tests of behavior.
Cortisol consumption was monitored in blood samples (0.8 ml) obtained
from manually restrained monkeys by femoral venipuncture for
determinations of cortisol and ACTH using previously described procedures (Lyons et al., 1995 , 1999 ). Each monkey was sampled 10 min
after completion of the 10 daily trials 6, 8, 10, 18, and 28 d
after initiation of the cortisol treatment protocol. Most samples
(70%) were collected within 2 min of cage entry (median latency to
sample collection = 105 sec; range, 33-406 sec), and all but six
samples (<4%) were collected within 4 min. Plasma levels of squirrel
monkey cortisol and ACTH measured within these time limits by the use
of these procedures do not reflect stressful sampling effects (Lyons et
al., 1995 , 1999 ).
Data analysis. Behavioral data were analyzed with
repeated-measures ANOVA. The box-opening orientation was
considered a within-subjects factor, whereas age and treatment were
considered between-subjects factors. Similar ANOVAs were used to
analyze plasma levels of cortisol and ACTH.
For straight-facing test trials, a standard index of manual laterality
was derived by subtracting the number of left-hand retrievals from the
number of right-hand retrievals and dividing the difference by the
total number of retrievals (Westergaard et al., 1998 ). This index
quantifies manual laterality along a continuum from strongly
left-handed (negative scores) to strongly right-handed (positive
scores), with zero indicating the absence of a lateral bias. Each
monkey's manual laterality score was considered statistically
significant (p < 0.01) when the binomial
z-score-transformed value exceeded 2.54, as described
elsewhere in greater detail (Milliken et al., 1991 ).
To estimate the independent contributions of age, cortisol treatment,
and manual laterality effects on the propensity to inhibit line-of-sight reaching, an ordered series of linear least squares regression equations was analyzed by the use of the hierarchical approach (Cohen and Cohen, 1983 ). This regression analysis and the
ANOVAs described above were performed with the MGLH module in
Systat (Evanston, IL). All test statistics were evaluated with two-tailed probabilities, and descriptive statistics are presented as
the mean ± SEM.
 |
RESULTS |
All monkeys retrieved the marshmallow treat with their first reach
attempt on each of the training trials administered with the box
opening oriented straight. When subsequent straight-facing test trials
were interspersed among trials administered with the box opening
oriented toward either side, the marshmallow treat was also retrieved
but often after reaches that failed to result in the immediate recovery
of the food. On average, each monkey made 26 ± 6 reach attempt
errors (mean ± SEM) on test trials administered with the box
opening oriented straight. Twice as many errors (56 ± 4) were
made by each monkey when the opening was oriented toward the left or
right [F(1,31) = 5.21;
p < 0.03 for error rates standardized on a per trial
basis].
Errors with the box opening oriented straight
Most test trials administered with the box opening oriented
straight (75%) were preceded immediately by a trial conducted with the
opening oriented toward the right (Fig. 1). Despite this regularity,
monkeys did not exhibit a tendency to repeat the previously correct
response; 47 ± 5% of all errors were toward the left, and
42 ± 5% of all errors were toward the right. A small percentage of errors were reach attempts directed toward the top of the box (2 ± 1%) or were handling errors performed inside the box that failed to result in the recovery of food (9 ± 2%). Age- and
cortisol treatment-related differences were not statistically
significant for any of these errors committed on test trials with the
box opening oriented straight.
Errors with the box opening oriented left or right
Each test trial administered with the box opening oriented left
was preceded immediately by a trial conducted with the opening oriented
straight (Fig. 1). In a similar manner, each trial administered with
the box opening oriented right was preceded immediately by a trial
conducted with the opening oriented toward the left. Despite these
regularities in the orientation of the opening, most errors consisted
of line-of-sight reaches directed straight toward the box. When the box
opening was oriented left, 36 ± 3% of all errors were directed
toward the right, whereas 55 ± 3% of all errors were
line-of-sight reaches directed straight toward the box
[F(1,28) = 16.7; p < 0.001]. Identical outcomes were evident when the box opening was
oriented right; 37 ± 3% of all errors were directed toward the
left, whereas 55 ± 3% of all errors were line-of-sight reaches
directed straight toward the box
[F(1,28) = 17.3; p < 0.001].
Both age and the cortisol treatment influenced performance on trials
conducted with the opening oriented toward either side. Line-of-sight
response inhibition errors directed straight toward the box were
performed most often by the older adults. Treatment with cortisol
increased response inhibition errors in both the older and young adult
monkeys (Fig. 2). Significant main
effects for age [F(1,28) = 8.18;
p < 0.01] and treatment
[F(1,28) = 5.48; p < 0.05] were discerned in the age (young vs older) × treatment (cortisol vs placebo) × box opening (left vs right) ANOVA. The box orientation main effect and all four interaction terms in this
analysis were not statistically significant.

View larger version (24K):
[in this window]
[in a new window]
|
Figure 2.
Response inhibition errors directed straight
toward the box when the box opening was oriented toward the left
(a) or right (b) were
evident more often in older adults. Chronic treatment with cortisol
increased this propensity in older and young adult monkeys
(n = 8 monkeys per condition).
|
|
Response inhibition errors directed straight toward the box when the
opening was oriented toward either side were grouped into 7 d
blocks of repeated trials and analyzed for changes over time (Fig.
3). Error rates declined with repeated
test trials as revealed by ANOVA [repeated-blocks main effect
F(2,56) = 35.63; p < 0.001]. Age-related differences in response inhibition errors were
consistent across blocks of repeated test trials [age main effect
F(1,28) = 7.47; p < 0.02], whereas treatment effects were clearly expressed only on the
last block of trials [F(1,28) = 5.02;
p < 0.05].

View larger version (23K):
[in this window]
[in a new window]
|
Figure 3.
Results from repeated measures ANOVA showed that
age-related differences in response inhibition errors were consistent
across 7 d blocks of repeated trials (a;
n = 16 monkeys per age group), whereas treatment
effects were clearly expressed only after prolonged exposure to
cortisol (b; n = 16 monkeys per
treatment).
|
|
Individual differences in manual laterality
Reach attempt errors performed within a given trial preceded the
retrieval of food. Nearly all retrievals were performed with the hand
ipsilateral to the box opening on left- and right-oriented test trials.
The so-called awkward retrieval was performed with the contralateral
hand <4% of the time. Age- and cortisol treatment-related differences
were not significant for awkward retrievals performed using the
contralateral hand.
Individual differences in manual laterality were discerned on trials
conducted with the box opening oriented straight. During the series of
100 training trials, 16 monkeys demonstrated a significant left-hand bias (p < 0.01), 13 monkeys
demonstrated a significant right-hand bias (p < 0.01), and 3 monkeys were scored as ambidextrous. Individual
differences in manual laterality during training predicted subsequent
differences in manual laterality scored on the 84 straight-facing test
trials (intraclass correlation = 0.91; p < 0.001).
Manual laterality and response inhibition
Reliable differences in manual laterality predicted differences in
the propensity to inhibit, when required, the line-of-sight reaching
response. Significantly fewer line-of-sight response inhibition errors
were performed by monkeys with a left-hand bias, regardless of whether
the box opening was oriented toward the left or right (Fig.
4). A significant manual laterality main
effect [F(2,29) = 4.04;
p < 0.03] was discerned by ANOVA, but the box-opening orientation main effect and manual laterality × box-opening
interaction failed to achieve statistical significance.

View larger version (31K):
[in this window]
[in a new window]
|
Figure 4.
Monkeys with a left-hand bias
(n = 16) performed significantly fewer response
inhibition errors when the box opening was oriented toward the left
(a) or right (b) compared
with monkeys with a right-hand bias (n = 13) or
monkeys scored as ambidextrous (n = 3).
|
|
The relationship between response inhibition and laterality was not
caused by spurious age or treatment effects as indicated by
hierarchical regression analysis. With age entered first in the linear
least squares equation, the difference between young and older adults
explained 17% of the variance in response inhibition errors made with
the box opening oriented toward either side
[F(1,30) = 6.16; p < 0.02]. With age and cortisol treatment entered together in the
subsequent regression equation, an additional 11% of the variance in
response inhibition errors was explained by placebo-controlled treatment with cortisol [F(1,29) = 4.62; p < 0.05] beyond that attributed to the age
effect alone. With age, treatment, and manual laterality all entered in
the final equation, an additional 10% of the variance in response
inhibition errors was explained by manual laterality
[F(1,28) = 4.28; p < 0.05] beyond that attributed to age and treatment with cortisol.
Neuroendocrine assessments
Chronic treatment with cortisol in drinking water resulted in
stress-like increases in plasma cortisol levels and reductions in
plasma levels of ACTH. Mean cortisol levels in the cortisol-treated monkeys were significantly greater than those in the placebo controls [437 ± 41 vs 144 ± 17 µg/dl;
F(1,28) = 49.8; p < 0.001]. The converse was evident for ACTH [10 ± 2 vs 52 ± 8 pg/ml; F(1,28) = 23.2; p < 0.001]. Age-related main effects and age × cortisol treatment interactions were not statistically significant.
 |
DISCUSSION |
Stress-level cortisol treatment impaired response inhibition at a
level less severe than that reported previously for prefrontal lesions
(Diamond et al., 1989 ; Diamond, 1990 ; Dias et al., 1996 ) and diminished
prefrontal dopamine use in monkeys treated repeatedly with
phencyclidine (Jentsch et al., 1997 , 1999 ). Failure to inhibit line-of-sight reaching was evident more often in older squirrel monkey
adults. Treatment with cortisol increased this propensity in both older
and young adult monkeys. Age-related differences in response inhibition
were consistent across blocks of repeated test trials, but the
treatment effects were clearly expressed only after prolonged exposure
to cortisol. Aspects of performance that did not require inhibition
were not altered by age or treatment with cortisol, which concurs with
effects on response inhibition rather than nonspecific changes in behavior.
Most studies of cortisol-induced cognitive impairments in humans have
focused on hippocampal-dependent memory. Four days of placebo-controlled stress-level cortisol administered to healthy humans
impairs hippocampal-dependent memory (Newcomer et al., 1999 ), as does
stress-induced increases in endogenous cortisol levels (Kirschbaum et
al., 1996 ; Lupien et al., 1997 ) and elevated cortisol at baseline
(Lupien et al., 1998 ). Endogenous hypercortisolism has been associated
with hippocampal atrophy and deficits in declarative memory in patients
with Cushing's syndrome, dementia of the Alzheimer type,
schizophrenia, and major depression (de Leon et al., 1988 ; O'Brien et
al., 1996 ; Nelson et al., 1998 ; Newcomer et al., 1998 ; Sheline et al.,
1999 ; Starkman et al., 1999 ).
Our findings reflect a different aspect of cognition because surgical
ablations that impair hippocampal-dependent memory spare inhibition in
monkeys assessed on the line-of-sight reaching response test (Diamond
et al., 1989 ). Chronic treatment with hydrocortisone in healthy young
men also produces spatial working-memory deficits that resemble those
seen in surgical patients after frontal lobe excisions, but not
temporal lobe excisions or amygdalo-hippocampectomies (Young et al.,
1999 ). Another study reported in healthy young men that
prefrontal-dependent item-recognition working memory is impaired by
acute high-dose hydrocortisone infusions administered shortly before
and during cognitive testing (Lupien et al., 1999 ). Continuous
treatment with cortisol in squirrel monkeys did not immediately
influence response inhibition, but prefrontal-dependent inhibitory
deficits in monkeys emerged over repeated test trials.
As demonstrated previously in vervet monkey research (Taylor et al.,
1990b ), response inhibition errors directed straight toward the box
when the opening was oriented toward either side decreased over
repeated test trials. Consistent age-related differences in response
inhibition errors were evident in squirrel monkeys across blocks of
repeated trials, but cortisol treatment effects on response inhibition
were confined to the last block of trials. Daily treatments of
corticosterone likewise diminish inhibitory control of goal-directed
routines in studies conducted with rodents (Hennessy et al., 1973 ;
Micco et al., 1979 ). But while learning to perform these simple
routines, rats treated daily with corticosterone did not differ
significantly from placebo controls (Hennessy et al., 1973 ).
Impaired response inhibition occurs regularly in older animals (Bartus
et al., 1979 ; Means and Holsten, 1992 ; Milgram et al., 1994 ) and is
linked in older humans to age-related atrophy in prefrontal volumes
assessed in vivo by magnetic resonance imaging (Raz et al.,
1998 ; Kim et al., 1999 ). Research on normal aging has not consistently
established a loss of neurons in primate prefrontal cortex (Peters,
1993 ), but other age-related changes are known to occur. These include
a reduction in cerebral white matter volumes (Peters et al., 1996 ),
breakdown in the integrity of myelin around axons (Peters et al.,
2000 ), diminished synaptic densities in prefrontal cortex (Peters et
al., 1998 ), and a decline in prefrontal dopamine levels (Goldman-Rakic
and Brown, 1981 ; Wenk et al., 1989 ).
Recent evidence suggests that prefrontal cognitive deficits may arise
from disruptions in forebrain dopamine neurotransmission induced by
excessive exposure to cortisol. Glucocorticoid receptors bind cortisol
in dopamine cell bodies (Harfstrand et al., 1986 ) and primate
prefrontal cortex (Sanchez et al., 2000 ). Cortisol-induced disruptions
in dopamine neurochemistry have not yet been examined in primates, but
treatment with corticosterone or its removal by adrenalectomy alters
forebrain dopamine physiology in rodents. Both increased and diminished
dopamine levels have been found after treatment with
corticosterone in rats (Thomas et al., 1994 ; Piazza et al., 1996 ;
Lindley et al., 1999 ). These outcomes may reflect glucocorticoid
regulation of dopamine release (Thomas et al., 1994 ; Piazza et al.,
1996 ), extrasynaptic reuptake (Grundemann et al., 1998 ), or changes in
dopamine metabolism (Lindley et al., 1999 ).
Either excessive or insufficient dopamine neurotransmission can impair
prefrontal cognitive functions. Depletion of dopamine in prefrontal
cortex (Brozoski et al., 1979 ; Collins et al., 1998 ) and acute noise
stress-induced increases in prefrontal dopamine release (Arnsten and
Goldman-Rakic, 1998 ) each produce similar deficits in monkeys assessed
on delayed spatial working-memory tests. An inverted U-shaped
relationship is also evident in rodents. Depletion of dopamine in rat
prefrontal cortex (Simon et al., 1980 ; Bubser and Schmidt, 1990 ) and
supranormal stimulation of prefrontal dopamine D1 receptors (Zahrt et
al., 1997 ) both disrupt cognitive performance on delayed spatial
alternation tests. Intracellular recordings from rodent prefrontal
cortical slices are consistent with the possibility that these
cognitive deficits arise from dopamine modulation of signal transfer to
the soma from the dendritic tree (Zahrt et al., 1997 ; Birnbaum et al.,
1999 ).
Among humans with stress-related psychiatric disorders, those with
psychotic depression present most consistently with evidence of
endogenous hypercortisolism (Evans et al., 1983 ; Nelson and Davis,
1997 ) and are impaired on tests of prefrontal-dependent functions
including attention and response inhibition (Jeste et al., 1996 ; Kim et
al., 1999 ; Schatzberg et al., 2000 ). More recently a study of
Cushing's syndrome indicates that prolonged exposure to elevated
cortisol disrupts selective attention, response inhibition, and
performance on prefrontal-dependent tasks (Forget et al., 2000 ). On the
basis of these findings in humans and animals, we now are investigating
prefrontal cognitive functions before and after the administration of a
steroid antagonist in humans with psychotic depression.
A final aspect of this study that warrants comment concerns
line-of-sight reaching and manual laterality. Squirrel monkeys that
presented with a left- or right-hand bias were nearly equally common in
the sample we examined. This finding is consistent with 26 other
primate species that all fail to exhibit a population-level lateral
bias for simple retrieval behavior (Fagot and Vauclair, 1991 ). Far less
is known about manual laterality and cognitive processing in primates.
Reach attempt errors directed straight toward the box when the opening
was oriented toward either side were made less often by squirrel
monkeys in this study that presented with a left-hand bias. Left-hand
(right cerebral hemisphere) superiority for tactile-spatial cognitive
processing has been demonstrated previously in primates (Brizzolara et
al., 1982 ; Horster and Ettlinger, 1985 ; Parr et al., 1997 ). Right
hemispheric dominance for response inhibition has also been identified
by event-related functional magnetic resonance imaging in healthy
humans tested on go/no-go tasks using either hand (Konishi et al.,
1998 ; Garavan et al., 1999 ). Right hemispheric dominance for response
inhibition and lateral differences in spatial cognitive processing may
account for the left-hand superiority in squirrel monkeys assessed on the line-of-sight reaching response test. Neuroimaging research with
monkeys and apes may shed light on these aspects of cerebral lateralization and their role in prefrontal-dependent functions.
 |
FOOTNOTES |
Received April 20, 2000; revised July 14, 2000; accepted Aug. 3, 2000.
This research was supported by the Nancy Pritzker Network and Public
Health Service (Washington, D.C.) Grant MH 47573. We gratefully
acknowledge Erica Didier, Tom Jordan, and Sonia Lupien for their advice
and technical assistance.
Correspondence should be addressed to Dr. David M. Lyons at the above
address. E-mail: dmlyons{at}stanford.edu.
 |
REFERENCES |
-
Arnsten AF,
Goldman-Rakic PS
(1998)
Noise stress impairs prefrontal cortical cognitive function in monkeys: evidence for a hyperdopaminergic mechanism.
Arch Gen Psychiatry
55:362-368[Abstract/Free Full Text].
-
Bartus RT,
Dean RL,
Fleming DL
(1979)
Aging in the rhesus monkey: effects on visual discrimination learning and reversal learning.
J Gerontol
34:209-219[Abstract/Free Full Text].
-
Birnbaum S,
Gobeske KT,
Auerbach J,
Taylor JR,
Arnsten AF
(1999)
A role for norepinephrine in stress-induced cognitive deficits: alpha-1-adrenoceptor mediation in the prefrontal cortex.
Biol Psychiatry
46:1266-1274[Web of Science][Medline].
-
Brady AG
(2000)
Research techniques for the squirrel monkey (Saimiri).
ILAR J
41:10-18[Medline].
-
Brizzolara D,
De Nobili GL,
Ferretti G
(1982)
Tactile discrimination of direction of lines in relation to hemispheric specialization.
Percept Mot Skills
54:655-660[Web of Science][Medline].
-
Brozoski TJ,
Brown RM,
Rosvold HE,
Goldman PS
(1979)
Cognitive deficit caused by regional depletion of dopamine in prefrontal cortex of rhesus monkey.
Science
205:929-932[Abstract/Free Full Text].
-
Bubser M,
Schmidt WJ
(1990)
6-Hydroxydopamine lesion of the rat prefrontal cortex increases locomotor activity, impairs acquisition of delayed alternation tasks, but does not affect uninterrupted tasks in the radial maze.
Behav Brain Res
37:157-168[Web of Science][Medline].
-
Cohen J,
Cohen P
(1983)
In: Applied multiple regression/correlation analysis for the behavioral sciences, 2nd Edition. Hillsdale, NJ: Erlbaum.
-
Collins P,
Roberts AC,
Dias R,
Everitt BJ,
Robbins TW
(1998)
Perseveration and strategy in a novel spatial self-ordered sequencing task for nonhuman primates: effects of excitotoxic lesions and dopamine depletions of the prefrontal cortex.
J Cognit Neurosci
10:332-354[Web of Science][Medline].
-
de Kloet ER,
Oitzl MS,
Joels M
(1999)
Stress and cognition: are corticosteroids good or bad guys?
Trends Neurosci
22:422-426[Web of Science][Medline].
-
de Leon MJ,
McRae T,
Tsai JR,
George AE,
Marcus DL,
Freedman M,
Wolf AP,
McEwen B
(1988)
Abnormal cortisol response in Alzheimer's disease linked to hippocampal atrophy.
Lancet
2:391-392[Medline].
-
Diamond A
(1990)
Developmental time course in human infants and infant monkeys, and the neural bases of, inhibitory control of reaching.
Ann NY Acad Sci
608:637-676[Web of Science][Medline].
-
Diamond A,
Zola-Morgan S,
Squire LR
(1989)
Successful performance by monkeys with lesions of the hippocampal formation on AB and object retrieval, two tasks that mark developmental changes in human infants.
Behav Neurosci
103:526-537[Web of Science][Medline].
-
Dias R,
Robbins TW,
Roberts AC
(1996)
Primate analogue of the Wisconsin Card Sorting Test: effects of excitotoxic lesions of the prefrontal cortex in the marmoset.
Behav Neurosci
110:872-886[Web of Science][Medline].
-
Di Paolo T,
Bedard P,
Daigle M,
Boucher R
(1986)
Long-term effects of MPTP on central and peripheral catecholamine and indoleamine concentrations in monkeys.
Brain Res
379:286-293[Web of Science][Medline].
-
Elsworth JD,
Deutch AY,
Redmond Jr DE,
Sladek Jr JR,
Roth RH
(1987)
Effects of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) on catecholamines and metabolites in primate brain and CSF.
Brain Res
415:293-299[Web of Science][Medline].
-
Evans DL,
Burnett GB,
Nemeroff CB
(1983)
The dexamethasone suppression test in the clinical setting.
Am J Psychiatry
140:586-589[Abstract/Free Full Text].
-
Fagot J,
Vauclair J
(1991)
Manual laterality in nonhuman primates: a distinction between handedness and manual specialization.
Psychol Bull
109:76-89[Web of Science][Medline].
-
Forget H,
Lacroiz A,
Somma M,
Cohen H
(2000)
Cognitive decline in patients with Cushing's syndrome.
J Int Neuropsychol Soc
6:20-29[Web of Science][Medline].
-
Garavan H,
Ross TJ,
Stein EA
(1999)
Right hemispheric dominance of inhibitory control: an event-related functional MRI study.
Proc Natl Acad Sci USA
96:8301-8306[Abstract/Free Full Text].
-
Goldman-Rakic PS,
Brown RM
(1981)
Regional changes of monoamines in cerebral cortex and subcortical structures of aging rhesus monkeys.
Neuroscience
6:177-187[Web of Science][Medline].
-
Grundemann D,
Schechinger B,
Rappold GA,
Schomig E
(1998)
Molecular identification of the corticosterone-sensitive extraneuronal catecholamine transporter.
Nat Neurosci
1:349-351[Web of Science][Medline].
-
Harfstrand A,
Fuxe K,
Cintra A,
Agnati LF,
Zini I,
Wikstrom AC,
Okret S,
Yu ZY,
Goldstein M,
Steinbusch H,
Verhofstad A,
Gustafsson J
(1986)
Glucocorticoid receptor immunoreactivity in monoaminergic neurons of rat brain.
Proc Natl Acad Sci USA
83:9779-9783[Abstract/Free Full Text].
-
Hennessy JW,
Cohen ME,
Rosen AJ
(1973)
Adrenocortical influences upon the extinction of an appetitive runway response.
Physiol Behav
11:767-770[Medline].
-
Horster W,
Ettlinger G
(1985)
An association between hand preference and tactile discrimination performance in the rhesus monkey.
Neuropsychologia
23:411-413[Web of Science][Medline].
-
Jentsch JD,
Redmond Jr DE,
Elsworth JD,
Taylor JR,
Youngren KD,
Roth RH
(1997)
Enduring cognitive deficits and cortical dopamine dysfunction in monkeys after long-term administration of phencyclidine.
Science
277:953-955[Abstract/Free Full Text].
-
Jentsch JD,
Taylor JR,
Elsworth JD,
Redmond Jr DE,
Roth RH
(1999)
Altered frontal cortical dopaminergic transmission in monkeys after subchronic phencyclidine exposure: involvement in frontostriatal cognitive deficits.
Neuroscience
90:823-832[Web of Science][Medline].
-
Jeste DV,
Heaton SC,
Paulsen JS,
Ercoli L,
Harris J,
Heaton RK
(1996)
Clinical and neuropsychological comparison of psychotic depression with nonpsychotic depression and schizophrenia.
Am J Psychiatry
153:490-496[Abstract/Free Full Text].
-
Kim DK,
Kim BL,
Sohn SE,
Lim SW,
Na DG,
Paik CH,
Krishnan KR,
Carroll BJ
(1999)
Candidate neuroanatomic substrates of psychosis in old-aged depression.
Prog Neuropsychopharmacol Biol Psychiatry
23:793-807[Medline].
-
Kirschbaum C,
Wolf OT,
May M,
Wippich W,
Hellhammer DH
(1996)
Stress- and treatment-induced elevations of cortisol levels associated with impaired declarative memory in healthy adults.
Life Sci
58:1475-1483[Web of Science][Medline].
-
Konishi S,
Nakajima K,
Uchida I,
Sekihara K,
Miyashita Y
(1998)
No-go dominant brain activity in human inferior prefrontal cortex revealed by functional magnetic resonance imaging.
Eur J Neurosci
10:1209-1213[Web of Science][Medline].
-
Lindley SE,
Bengoechea TG,
Schatzberg AF,
Wong DL
(1999)
Glucocorticoid effects on mesotelencephalic dopamine neurotransmission.
Neuropsychopharmacology
21:399-407[Web of Science][Medline].
-
Lupien SJ,
Gaudreau S,
Tchiteya BM,
Maheu F,
Sharma S,
Nair NP,
Hauger RL,
McEwen BS,
Meaney MJ
(1997)
Stress-induced declarative memory impairment in healthy elderly subjects: relationship to cortisol reactivity.
J Clin Endocrinol Metab
82:2070-2075[Abstract/Free Full Text].
-
Lupien SJ,
de Leon M,
de Santi S,
Convit A,
Tarshish C,
Nair NP,
Thakur M,
McEwen BS,
Hauger RL,
Meaney MJ
(1998)
Cortisol levels during human aging predict hippocampal atrophy and memory deficits.
Nat Neurosci
1:69-73[Web of Science][Medline].
-
Lupien SJ,
Gillin CJ,
Hauger RL
(1999)
Working memory is more sensitive than declarative memory to the acute effects of corticosteroids: a dose-response study in humans.
Behav Neurosci
113:420-430[Web of Science][Medline].
-
Lyons DM,
Ha CM,
Levine S
(1995)
Social effects and circadian rhythms in squirrel monkey pituitary-adrenal activity.
Horm Behav
29:177-190[Medline].
-
Lyons DM,
Wang OJ,
Lindley SE,
Levine S,
Kalin NH,
Schatzberg AF
(1999)
Separation induced changes in squirrel monkey hypothalamic-pituitary-adrenal physiology resemble aspects of hypercortisolism in humans.
Psychoneuroendocrinology
24:131-142[Web of Science][Medline].
-
McEwen BS,
Sapolsky RM
(1995)
Stress and cognitive function.
Curr Opin Neurobiol
5:205-216[Web of Science][Medline].
-
Means LW,
Holsten RD
(1992)
Individual aged rats are impaired on repeated reversal due to loss of different behavioral patterns.
Physiol Behav
52:959-963[Medline].
-
Micco DJ,
McEwen BS,
Shein W
(1979)
Modulation of behavioral inhibition in appetitive extinction following manipulation of adrenal steroids in rats: implications for the involvement of the hippocampus.
J Comp Physiol Psychol
93:323-329[Web of Science][Medline].
-
Milgram NW,
Head E,
Weiner E,
Thomas E
(1994)
Cognitive functions and aging in the dog: acquisition of nonspatial visual tasks.
Behav Neurosci
108:57-68[Web of Science][Medline].
-
Milliken GW,
Stafford DK,
Dodson DL,
Pinger CD,
Ward JP
(1991)
Analyses of feeding lateralization in the small-eared bush baby (Otolemur garnettii): a comparison with the ring-tailed lemur (Lemur catta).
J Comp Psychol
105:274-285[Web of Science][Medline].
-
Nelson JC,
Davis JM
(1997)
DST studies in psychotic depression: a meta-analysis.
Am J Psychiatry
154:1497-1503[Abstract/Free Full Text].
-
Nelson MD,
Saykin AJ,
Flashman LA,
Riordan HJ
(1998)
Hippocampal volume reduction in schizophrenia as assessed by magnetic resonance imaging: a meta-analytic study.
Arch Gen Psychiatry
55:433-440[Abstract/Free Full Text].
-
Newcomer JW,
Craft S,
Askins K,
Hershey T,
Bardgett ME,
Csernansky JG,
Gagliardi AE,
Vogler G
(1998)
Glucocorticoid interactions with memory function in schizophrenia.
Psychoneuroendocrinology
23:65-72[Web of Science][Medline].
-
Newcomer JW,
Selke G,
Melson AK,
Hershey T,
Craft S,
Richards K,
Alderson AL
(1999)
Decreased memory performance in healthy humans induced by stress-level cortisol treatment.
Arch Gen Psychiatry
56:527-533[Abstract/Free Full Text].
-
O'Brien JT,
Ames D,
Schweitzer I,
Colman P,
Desmond P,
Tress B
(1996)
Clinical and magnetic resonance imaging correlates of hypothalamic-pituitary-adrenal axis function in depression and Alzheimer's disease.
Br J Psychiatry
168:679-687[Abstract/Free Full Text].
-
Parr LA,
Hopkins WD,
de Waal FB
(1997)
Haptic discrimination in capuchin monkeys (Cebus apella): evidence of manual specialization.
Neuropsychologia
35:143-152[Web of Science][Medline].
-
Peters A
(1993)
The absence of significant neuronal loss from cerebral cortex with age.
Neurobiol Aging
14:657-658[Web of Science][Medline].
-
Peters A,
Rosene DL,
Moss MB,
Kemper TL,
Abraham CR,
Tigges J,
Albert MS
(1996)
Neurobiological bases of age-related cognitive decline in the rhesus monkey.
J Neuropathol Exp Neurol
55:861-874[Web of Science][Medline].
-
Peters A,
Sethares C,
Moss MB
(1998)
The effects of aging on layer 1 in area 46 of prefrontal cortex in the rhesus monkey.
Cereb Cortex
8:671-684[Abstract/Free Full Text].
-
Peters A,
Moss MB,
Sethares C
(2000)
Effects of aging on myelinated nerve fibers in monkey primary visual cortex.
J Comp Neurol
419:364-376[Web of Science][Medline].
-
Piazza PV,
Rouge-Pont F,
Deroche V,
Maccari S,
Simon H,
Le Moal M
(1996)
Glucocorticoids have state-dependent stimulant effects on the mesencephalic dopaminergic transmission.
Proc Natl Acad Sci USA
93:8716-8720[Abstract/Free Full Text].
-
Raz N,
Gunning-Dixon FM,
Head D,
Dupuis JH,
Acker JD
(1998)
Neuroanatomical correlates of cognitive aging: evidence from structural magnetic resonance imaging.
Neuropsychology
12:95-114[Web of Science][Medline].
-
Roberts AC,
De Salvia MA,
Wilkinson LS,
Collins P,
Muir JL,
Everitt BJ,
Robbins TW
(1994)
6-Hydroxydopamine lesions of the prefrontal cortex in monkeys enhance performance on an analog of the Wisconsin Card Sort Test: possible interactions with subcortical dopamine.
J Neurosci
14:2531-2544[Abstract].
-
Sanchez MM,
Young LJ,
Plotsky PM,
Insel TR
(2000)
Distribution of corticosteroid receptors in the rhesus brain: relative absence of glucocorticoid receptors in the hippocampal formation.
J Neurosci
20:4657-4668[Abstract/Free Full Text].
-
Schatzberg AF,
Posener JA,
DeBattista C,
Kalehzan BM,
Rothschild AJ,
Shear PK
(2000)
Neuropsychological deficits in psychotic versus nonpsychotic major depression and no mental illness.
Am J Psychiatry
157:1095-1100[Abstract/Free Full Text].
-
Sheline YI,
Sanghavi M,
Mintun MA,
Gado MH
(1999)
Depression duration but not age predicts hippocampal volume loss in medically healthy women with recurrent major depression.
J Neurosci
19:5034-5043[Abstract/Free Full Text].
-
Simon H,
Scatton B,
Moal ML
(1980)
Dopaminergic A10 neurones are involved in cognitive functions.
Nature
286:150-151[Medline].
-
Slovin H,
Abeles M,
Vaadia E,
Haalman I,
Prut Y,
Bergman H
(1999)
Frontal cognitive impairments and saccadic deficits in low-dose MPTP-treated monkeys.
J Neurophysiol
81:858-874[Abstract/Free Full Text].
-
Starkman MN,
Giordani B,
Gebarski SS,
Berent S,
Schork MA,
Schteingart DE
(1999)
Decrease in cortisol reverses human hippocampal atrophy following treatment of Cushing's disease.
Biol Psychiatry
46:1595-1602[Web of Science][Medline].
-
Taylor JR,
Elsworth JD,
Roth RH,
Collier TJ,
Sladek Jr JR,
Redmond Jr DE
(1990a)
Improvements in MPTP-induced object retrieval deficits and behavioral deficits after fetal nigral grafting in monkeys.
Prog Brain Res
82:543-559[Web of Science][Medline].
-
Taylor JR,
Elsworth JD,
Roth RH,
Sladek Jr JR,
Redmond Jr DE
(1990b)
Cognitive and motor deficits in the acquisition of an object retrieval/detour task in MPTP-treated monkeys.
Brain
113:617-637[Abstract/Free Full Text].
-
Taylor JR,
Roth RH,
Sladek Jr JR,
Redmond Jr DE
(1990c)
Cognitive and motor deficits in the performance of an object retrieval task with a barrier-detour in monkeys (Cercopithecus aethiops sabaeus) treated with MPTP: long-term performance and effect of transparency of the barrier.
Behav Neurosci
104:564-576[Web of Science][Medline].
-
Thomas DN,
Post RM,
Pert A
(1994)
Central and systemic corticosterone differentially affect dopamine and norepinephrine in the frontal cortex of the awake freely moving rat.
Ann NY Acad Sci
746:467-469[Web of Science][Medline].
-
Wenk GL,
Pierce DJ,
Struble RG,
Price DL,
Cork LC
(1989)
Age-related changes in multiple neurotransmitter systems in the monkey brain.
Neurobiol Aging
10:11-19[Web of Science][Medline].
-
Westergaard GC,
Byrne G,
Suomi SJ
(1998)
Early lateral bias in tufted capuchins (Cebus apella).
Dev Psychobiol
32:45-50[Web of Science][Medline].
-
Young AH,
Sahakian BJ,
Robbins TW,
Cowen PJ
(1999)
The effects of chronic administration of hydrocortisone on cognitive function in normal male volunteers.
Psychopharmacology (Berl)
145:260-266[Medline].
-
Zahrt J,
Taylor JR,
Mathew RG,
Arnsten AF
(1997)
Supranormal stimulation of D1 dopamine receptors in the rodent prefrontal cortex impairs spatial working memory performance.
J Neurosci
17:8528-8535[Abstract/Free Full Text].
Copyright © 2000 Society for Neuroscience 0270-6474/00/20207816-06$05.00/0
This article has been cited by other articles:

|
 |

|
 |
 
B. Roozendaal, J. R. McReynolds, E. A. Van der Zee, S. Lee, J. L. McGaugh, and C. K. McIntyre
Glucocorticoid Effects on Memory Consolidation Depend on Functional Interactions between the Medial Prefrontal Cortex and Basolateral Amygdala
J. Neurosci.,
November 11, 2009;
29(45):
14299 - 14308.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
S. M. Brown, S. Henning, and C. L. Wellman
Mild, Short-term Stress Alters Dendritic Morphology in Rat Medial Prefrontal Cortex
Cereb Cortex,
November 1, 2005;
15(11):
1714 - 1722.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
E. van voorhees and A. Scarpa
The Effects of Child Maltreatment on the Hypothalamic-Pituitary-Adrenal Axis
Trauma Violence Abuse,
October 1, 2004;
5(4):
333 - 352.
[Abstract]
[PDF]
|
 |
|

|
 |

|
 |
 
D. M. Lyons, C. Yang, S. Eliez, A. L. Reiss, and A. F. Schatzberg
Cognitive Correlates of White Matter Growth and Stress Hormones in Female Squirrel Monkey Adults
J. Neurosci.,
April 7, 2004;
24(14):
3655 - 3662.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
B. Roozendaal, J. R. McReynolds, and J. L. McGaugh
The Basolateral Amygdala Interacts with the Medial Prefrontal Cortex in Regulating Glucocorticoid Effects on Working Memory Impairment
J. Neurosci.,
February 11, 2004;
24(6):
1385 - 1392.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
E. S. Brown, A. Frol, L. Bobadilla, V. A. Nejtek, D. C. Perantie, and H. Dhillon
Effect of Lamotrigine on Mood and Cognition in Patients Receiving Chronic Exogenous Corticosteroids
Psychosomatics,
June 1, 2003;
44(3):
204 - 208.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
J. K. Belanoff, M. Kalehzan, B. Sund, S. K. Fleming Ficek, and A. F. Schatzberg
Cortisol Activity and Cognitive Changes in Psychotic Major Depression
Am J Psychiatry,
October 1, 2001;
158(10):
1612 - 1616.
[Abstract]
[Full Text]
[PDF]
|
 |
|
|

|