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Domes G, Heinrichs M, Gläscher J, Büchel C, Braus DF, Herpertz SC. Oxytocin attenuates amygdala responses to emotional faces regardless of valence. Biol Psychiatry 2007; 62:1187-90. [PMID: 17617382 DOI: 10.1016/j.biopsych.2007.03.025] [Citation(s) in RCA: 579] [Impact Index Per Article: 32.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2006] [Revised: 03/06/2007] [Accepted: 03/30/2007] [Indexed: 11/20/2022]
Abstract
BACKGROUND Oxytocin is known to reduce anxiety and stress in social interactions as well as to modulate approach behavior. Recent studies suggest that the amygdala might be the primary neuronal basis for these effects. METHODS In a functional magnetic resonance imaging study using a double-blind, placebo-controlled within-subject design, we measured neural responses to fearful, angry, and happy facial expressions after intranasal application of 24 IU oxytocin compared with placebo. RESULTS Oxytocin reduced right-sided amygdala responses to all three face categories even when the emotional content of the presented face was not evaluated explicitly. Exploratory whole brain analysis revealed modulatory effects in prefrontal and temporal areas as well as in the brainstem. CONCLUSIONS Results suggest a modulatory role of oxytocin on amygdala responses to facial expressions irrespective of their valence. Reduction of amygdala activity to positive and negative stimuli might reflect reduced uncertainty about the predictive value of a social stimulus and thereby facilitates social approach behavior.
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Randomized Controlled Trial |
18 |
579 |
2
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Guastella AJ, Mitchell PB, Dadds MR. Oxytocin increases gaze to the eye region of human faces. Biol Psychiatry 2008; 63:3-5. [PMID: 17888410 DOI: 10.1016/j.biopsych.2007.06.026] [Citation(s) in RCA: 543] [Impact Index Per Article: 31.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/25/2007] [Revised: 06/28/2007] [Accepted: 06/29/2007] [Indexed: 12/15/2022]
Abstract
BACKGROUND In nonhuman mammals, oxytocin has a critical role in peer recognition and social approach behavior. In humans, oxytocin has been found to enhance trust and the ability to interpret the emotions of others. It has been suggested that oxytocin may enhance facial processing by increasing focus on the eye region of human faces. METHODS In a double-blind, randomized, placebo-controlled, between-subject design, we tracked the eye movements of 52 healthy male volunteers who were presented with 24 neutral human faces after intranasal administration of 24 IU oxytocin or placebo. RESULTS Participants given oxytocin showed an increased number of fixations and total gaze time toward the eye region compared with placebo participants. CONCLUSIONS Oxytocin increases gaze specifically toward the eye region of human faces. This may be one mechanism by which oxytocin enhances emotion recognition, interpersonal communication, and social approach behavior in humans. Findings suggest a possible role for oxytocin in the treatment of disorders characterized by eye-gaze avoidance and facial processing deficits.
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Randomized Controlled Trial |
17 |
543 |
3
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Downes JJ, Roberts AC, Sahakian BJ, Evenden JL, Morris RG, Robbins TW. Impaired extra-dimensional shift performance in medicated and unmedicated Parkinson's disease: evidence for a specific attentional dysfunction. Neuropsychologia 1989; 27:1329-43. [PMID: 2615934 DOI: 10.1016/0028-3932(89)90128-0] [Citation(s) in RCA: 364] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Groups of patients with Parkinson's disease, either medicated, or unmedicated and early in the course, together with age- and IQ-matched control subjects were tested in two paradigms measuring different aspects of selective attention. The first set of tests compared visual discrimination learning following intra- and extra-dimensional shifts, using a "total change" design in which each shift was made in the presence of novel exemplars of the compound stimuli used as discriminanda. The second test consisted of a visual search task in which the number of alternatives was varied. The results of the first experiment showed a selective deficit in both groups of Parkinsonian subjects in their ability to perform an extra-dimensional shift. In the visual search task, the patients were less accurate, but responded with equivalent choice reaction times to those of controls. The results are discussed in terms of the nature of the attentional dysfunction that occurs in Parkinson's disease.
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364 |
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Sahakian B, Jones G, Levy R, Gray J, Warburton D. The effects of nicotine on attention, information processing, and short-term memory in patients with dementia of the Alzheimer type. Br J Psychiatry 1989; 154:797-800. [PMID: 2597885 DOI: 10.1192/bjp.154.6.797] [Citation(s) in RCA: 340] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Nicotine in patients with dementia of the Alzheimer type (DAT) produced a significant and marked improvement in discriminative sensitivity and reaction times on a computerised test of attention and information processing. Nicotine also improved the ability of DAT patients to detect a flickering light in a critical flicker fusion test. These results suggest that nicotine may be acting on cortical mechanisms involved in visual perception and attention, and support the hypothesis that acetylcholine transmission modulates vigilance and discrimination. Nicotine may therefore be of some value in treating deficits in attention and information processing in DAT patients.
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Fusar-Poli P, Crippa JA, Bhattacharyya S, Borgwardt SJ, Allen P, Martin-Santos R, Seal M, Surguladze SA, O'Carrol C, Atakan Z, Zuardi AW, McGuire PK. Distinct effects of {delta}9-tetrahydrocannabinol and cannabidiol on neural activation during emotional processing. ARCHIVES OF GENERAL PSYCHIATRY 2009; 66:95-105. [PMID: 19124693 DOI: 10.1001/archgenpsychiatry.2008.519] [Citation(s) in RCA: 339] [Impact Index Per Article: 21.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
CONTEXT Cannabis use can both increase and reduce anxiety in humans. The neurophysiological substrates of these effects are unknown. OBJECTIVE To investigate the effects of 2 main psychoactive constituents of Cannabis sativa (Delta9-tetrahydrocannabinol [Delta9-THC] and cannabidiol [CBD]) on regional brain function during emotional processing. DESIGN Subjects were studied on 3 separate occasions using an event-related functional magnetic resonance imaging paradigm while viewing faces that implicitly elicited different levels of anxiety. Each scanning session was preceded by the ingestion of either 10 mg of Delta9-THC, 600 mg of CBD, or a placebo in a double-blind, randomized, placebo-controlled design. PARTICIPANTS Fifteen healthy, English-native, right-handed men who had used cannabis 15 times or less in their life. MAIN OUTCOME MEASURES Regional brain activation (blood oxygenation level-dependent response), electrodermal activity (skin conductance response [SCR]), and objective and subjective ratings of anxiety. RESULTS Delta9-Tetrahydrocannabinol increased anxiety, as well as levels of intoxication, sedation, and psychotic symptoms, whereas there was a trend for a reduction in anxiety following administration of CBD. The number of SCR fluctuations during the processing of intensely fearful faces increased following administration of Delta9-THC but decreased following administration of CBD. Cannabidiol attenuated the blood oxygenation level-dependent signal in the amygdala and the anterior and posterior cingulate cortex while subjects were processing intensely fearful faces, and its suppression of the amygdalar and anterior cingulate responses was correlated with the concurrent reduction in SCR fluctuations. Delta9-Tetrahydrocannabinol mainly modulated activation in frontal and parietal areas. CONCLUSIONS Delta9-Tetrahydrocannabinol and CBD had clearly distinct effects on the neural, electrodermal, and symptomatic response to fearful faces. The effects of CBD on activation in limbic and paralimbic regions may contribute to its ability to reduce autonomic arousal and subjective anxiety, whereas the anxiogenic effects of Delta9-THC may be related to effects in other brain regions.
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Randomized Controlled Trial |
16 |
339 |
6
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Daniels MJD, Rivers-Auty J, Schilling T, Spencer NG, Watremez W, Fasolino V, Booth SJ, White CS, Baldwin AG, Freeman S, Wong R, Latta C, Yu S, Jackson J, Fischer N, Koziel V, Pillot T, Bagnall J, Allan SM, Paszek P, Galea J, Harte MK, Eder C, Lawrence CB, Brough D. Fenamate NSAIDs inhibit the NLRP3 inflammasome and protect against Alzheimer's disease in rodent models. Nat Commun 2016; 7:12504. [PMID: 27509875 PMCID: PMC4987536 DOI: 10.1038/ncomms12504] [Citation(s) in RCA: 339] [Impact Index Per Article: 37.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Accepted: 07/06/2016] [Indexed: 12/13/2022] Open
Abstract
Non-steroidal anti-inflammatory drugs (NSAIDs) inhibit cyclooxygenase-1 (COX-1) and COX-2 enzymes. The NLRP3 inflammasome is a multi-protein complex responsible for the processing of the proinflammatory cytokine interleukin-1β and is implicated in many inflammatory diseases. Here we show that several clinically approved and widely used NSAIDs of the fenamate class are effective and selective inhibitors of the NLRP3 inflammasome via inhibition of the volume-regulated anion channel in macrophages, independently of COX enzymes. Flufenamic acid and mefenamic acid are efficacious in NLRP3-dependent rodent models of inflammation in air pouch and peritoneum. We also show therapeutic effects of fenamates using a model of amyloid beta induced memory loss and a transgenic mouse model of Alzheimer's disease. These data suggest that fenamate NSAIDs could be repurposed as NLRP3 inflammasome inhibitors and Alzheimer's disease therapeutics.
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research-article |
9 |
339 |
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Petrovic P, Kalisch R, Singer T, Dolan RJ. Oxytocin attenuates affective evaluations of conditioned faces and amygdala activity. J Neurosci 2008; 28:6607-15. [PMID: 18579733 PMCID: PMC2647078 DOI: 10.1523/jneurosci.4572-07.2008] [Citation(s) in RCA: 326] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2007] [Revised: 12/13/2007] [Accepted: 01/23/2008] [Indexed: 11/21/2022] Open
Abstract
Social relations between humans critically depend on our affective experiences of others. Oxytocin enhances prosocial behavior, but its effect on humans' affective experience of others is not known. We tested whether oxytocin influences affective ratings, and underlying brain activity, of faces that have been aversively conditioned. Using a standard conditioning procedure, we induced differential negative affective ratings in faces exposed to an aversive conditioning compared with nonconditioning manipulation. This differential negative evaluative effect was abolished by treatment with oxytocin, an effect associated with an attenuation of activity in anterior medial temporal and anterior cingulate cortices. In amygdala and fusiform gyrus, this modulation was stronger for faces with direct gaze, relative to averted gaze, consistent with a relative specificity for socially relevant cues. The data suggest that oxytocin modulates the expression of evaluative conditioning for socially relevant faces via influences on amygdala and fusiform gyrus, an effect that may explain its prosocial effects.
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research-article |
17 |
326 |
8
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Turner DC, Robbins TW, Clark L, Aron AR, Dowson J, Sahakian BJ. Cognitive enhancing effects of modafinil in healthy volunteers. Psychopharmacology (Berl) 2003; 165:260-9. [PMID: 12417966 DOI: 10.1007/s00213-002-1250-8] [Citation(s) in RCA: 321] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2002] [Accepted: 08/12/2002] [Indexed: 11/26/2022]
Abstract
RATIONALE Modafinil, a novel wake-promoting agent, has been shown to have a similar clinical profile to that of conventional stimulants such as methylphenidate. We were therefore interested in assessing whether modafinil, with its unique pharmacological mode of action, might offer similar potential as a cognitive enhancer, without the side effects commonly experienced with amphetamine-like drugs. OBJECTIVES The main aim of this study was to evaluate the cognitive enhancing potential of this novel agent using a comprehensive battery of neuropsychological tests. METHODS Sixty healthy young adult male volunteers received either a single oral dose of placebo, or 100 mg or 200 mg modafinil prior to performing a variety of tasks designed to test memory and attention. A randomised double-blind, between-subjects design was used. RESULTS Modafinil significantly enhanced performance on tests of digit span, visual pattern recognition memory, spatial planning and stop-signal reaction time. These performance improvements were complemented by a slowing in latency on three tests: delayed matching to sample, a decision-making task and the spatial planning task. Subjects reported feeling more alert, attentive and energetic on drug. The effects were not clearly dose dependent, except for those seen with the stop-signal paradigm. In contrast to previous findings with methylphenidate, there were no significant effects of drug on spatial memory span, spatial working memory, rapid visual information processing or attentional set-shifting. Additionally, no effects on paired associates learning were identified. CONCLUSIONS These data indicate that modafinil selectively improves neuropsychological task performance. This improvement may be attributable to an enhanced ability to inhibit pre-potent responses. This effect appears to reduce impulsive responding, suggesting that modafinil may be of benefit in the treatment of attention deficit hyperactivity disorder.
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Clinical Trial |
22 |
321 |
9
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Ornstein TJ, Iddon JL, Baldacchino AM, Sahakian BJ, London M, Everitt BJ, Robbins TW. Profiles of cognitive dysfunction in chronic amphetamine and heroin abusers. Neuropsychopharmacology 2000; 23:113-26. [PMID: 10882838 DOI: 10.1016/s0893-133x(00)00097-x] [Citation(s) in RCA: 286] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Groups of subjects whose primary drug of abuse was amphetamine or heroin were compared, together with age- and IQ-matched control subjects. The study consisted of a neuropsychological test battery which included both conventional tests and also computerised tests of recognition memory, spatial working memory, planning, sequence generation, visual discrimination learning, and attentional set-shifting. Many of these tests have previously been shown to be sensitive to cortical damage (including selective lesions of the temporal or frontal lobes) and to cognitive deficits in dementia, basal ganglia disease, and neuropsychiatric disorder. Qualitative differences, as well as some commonalities, were found in the profile of cognitive impairment between the two groups. The chronic amphetamine abusers were significantly impaired in performance on the extra-dimensional shift task (a core component of the Wisconsin Card Sort Test) whereas in contrast, the heroin abusers were impaired in learning the normally easier intra-dimensional shift component. Both groups were impaired in some of tests of spatial working memory. However, the amphetamine group, unlike the heroin group, were not deficient in an index of strategic performance on this test. The heroin group failed to show significant improvement between two blocks of a sequence generation task after training and additionally exhibited more perseverative behavior on this task. The two groups were profoundly, but equivalently impaired on a test of pattern recognition memory sensitive to temporal lobe dysfunction. These results indicate that chronic drug use may lead to distinct patterns of cognitive impairment that may be associated with dysfunction of different components of cortico-striatal circuitry.
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Clinical Trial |
25 |
286 |
10
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Baker KB, Kim JJ. Effects of stress and hippocampal NMDA receptor antagonism on recognition memory in rats. Learn Mem 2002; 9:58-65. [PMID: 11992016 PMCID: PMC155932 DOI: 10.1101/lm.46102] [Citation(s) in RCA: 234] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Exposures to uncontrollable stress have been shown to alter ensuing synaptic plasticity in the hippocampus and interfere with hippocampal-dependent spatial memory in rats. The present study examined whether stress, which impairs hippocampal long-term potentiation (LTP), also affects (nonspatial) hippocampal-dependent object-recognition memory, as tested on the visual paired comparison task (VPC) in rats. After undergoing an inescapable restraint-tailshock stress experience, rats exhibited markedly impaired recognition memory at the 3-h (long) familiarization-to-test phase delay but not at the 5-min (short) delay. In contrast, unstressed control animals showed robust recognition memory (i.e., they exhibited reliable preferences for novel over familiar objects) at both short- and long-delay periods. The impairing effect of stress on long-delay recognition memory was transient because 48 h after undergoing stress experience, animals performed normally at the long delay. Similar to stress, microinfusions of DL-2-amino-5-phosphonovaleric acid (APV), a competitive N-methyl-D-aspartate receptor (NMDAR) antagonist that blocks LTP, into the dorsal hippocampus selectively impaired object-recognition memory at the long-delay period. Together, these results suggest that stress and intrahippocampal administration of APV affect recognition memory by influencing synaptic plasticity in the hippocampus.
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research-article |
23 |
234 |
11
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Lamme VA, Zipser K, Spekreijse H. Figure-ground activity in primary visual cortex is suppressed by anesthesia. Proc Natl Acad Sci U S A 1998; 95:3263-8. [PMID: 9501251 PMCID: PMC19730 DOI: 10.1073/pnas.95.6.3263] [Citation(s) in RCA: 225] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
By means of their small receptive fields (RFs), neurons in primary visual cortex perform highly localized analyses of the visual scene, far removed from our normal unified experience of vision. Local image elements coded by the RF are put into more global context, however, by means of modulation of the responses of the V1 neurons. Contextual modulation has been shown to follow closely the perceptual interpretation of the scene as a whole. This would suggest that some aspects of contextual modulation can be recorded only in awake and perceiving animals. In this study, multi-unit activity was recorded with implanted electrodes from primary visual cortex of awake, fixating monkeys viewing textured displays in which figure and ground regions were segregated by differences in either orientation or motion. Contextual modulation was isolated from local RF processing, by keeping RF stimulation identical across trials while sampling responses for various positions of the RF relative to figure and ground. Contextual modulation was observed to unfold spatially and temporally in a way that closely resembles the figure-ground percept. When recording was repeated, but with the animals anesthetized, the figure-ground related modulatory activity was selectively suppressed. RF tuning properties, however, remained unaffected. The results show that the modulatory activity is functionally distinct from the RF properties. V1 thus hosts distinct regimes of activity that are mediated by separate mechanisms and that depend differentially on the animal being awake or anesthetized.
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research-article |
27 |
225 |
12
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Abstract
BACKGROUND Methylenedioxymethamphetamine (MDMA, or "Ecstasy") is a popular recreational drug of abuse that is known to damage brain serotonergic neurons in animals and possibly humans. Few functional consequences of MDMA-induced serotonin (5-HT) neurotoxicity have been identified, either in animals or humans. This study sought to determine whether individuals with a history of extensive MDMA use showed evidence of memory impairment, because brain serotonin has been implicated in mnemonic function. METHOD The authors compared 24 abstinent MDMA users and 24 control subjects on several standardized tests of memory, after matching subjects for age, gender, educational level, and vocabulary score (a surrogate of verbal intelligence). The authors also explored correlations between changes in memory function and decrements in CSF 5-hydroxyindoleacetic acid (5-HIAA), which serves as a marker of central 5-HT neural function. RESULTS Greater use of MDMA (total milligrams per month) was associated with greater impairment in immediate verbal memory (p < 0.02) and delayed visual memory (p < 0.06). Furthermore, lower vocabulary scores were associated with stronger dose-related effects, with men having greater dose-related deficits than women. Lastly, lower concentrations of CSF 5-HIAA were associated with poorer memory performance. CONCLUSION Abstinent MDMA users have impairment in verbal and visual memory. The extent of memory impairment correlates with the degree of MDMA exposure and the reduction in brain 5-HT, as indexed by CSF 5-HIAA.
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224 |
13
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Abstract
Schizophrenia is widely thought to involve deficits of attention. However, the term "attention" can be defined so broadly that impaired performance on virtually any task could be construed as evidence for a deficit in attention, and this has slowed cumulative progress in understanding attention deficits in schizophrenia. To address this problem, we divide the general concept of attention into two distinct constructs: input selection, the selection of task-relevant inputs for further processing; and rule selection, the selective activation of task-appropriate rules. These constructs are closely tied to working memory, because input selection mechanisms are used to control the transfer of information into working memory and because working memory stores the rules used by rule selection mechanisms. These constructs are also closely tied to executive function, because executive systems are used to guide input selection and because rule selection is itself a key aspect of executive function. Within the domain of input selection, it is important to distinguish between the control of selection--the processes that guide attention to task-relevant inputs--and the implementation of selection--the processes that enhance the processing of the relevant inputs and suppress the irrelevant inputs. Current evidence suggests that schizophrenia involves a significant impairment in the control of selection but little or no impairment in the implementation of selection. Consequently, the CNTRICS (Cognitive Neuroscience Treatment Research to Improve Cognition in Schizophrenia) participants agreed by consensus that attentional control should be a priority target for measurement and treatment research in schizophrenia.
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Consensus Development Conference, NIH |
17 |
211 |
14
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Sprengelmeyer R, Young AW, Mahn K, Schroeder U, Woitalla D, Büttner T, Kuhn W, Przuntek H. Facial expression recognition in people with medicated and unmedicated Parkinson's disease. Neuropsychologia 2003; 41:1047-57. [PMID: 12667540 DOI: 10.1016/s0028-3932(02)00295-6] [Citation(s) in RCA: 211] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Recognition of facial expressions of emotion was investigated in people with medicated and unmedicated Parkinson's disease (PD) and matched controls (unmedicated PD, n=16; medicated PD, n=20; controls, n=40). Participants in the medicated group showed some visual impairment (impaired contrast sensitivity) and performed less well on perception of unfamiliar face identity, but did not show significant deficits in the perception of sex, gaze direction, or familiar identity from the face. For both Parkinson's disease groups, there was evidence of impaired recognition of facial expressions in comparison to controls. These deficits were more consistently noted in the unmedicated group, who were also found to perform worse than the medicated group at recognising disgust from prototypical facial expressions, and at recognising anger and disgust in computer-manipulated images. Although both Parkinson's disease groups showed impairments of facial expression recognition, the consistently worse recognition of disgust in the unmedicated group is consistent with the hypothesis from previous studies that brain regions modulated by dopaminergic neurons are involved in the recognition of disgust.
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Comparative Study |
22 |
211 |
15
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Hassel S, Almeida JR, Kerr N, Nau S, Ladouceur CD, Fissell K, Kupfer DJ, Phillips ML. Elevated striatal and decreased dorsolateral prefrontal cortical activity in response to emotional stimuli in euthymic bipolar disorder: no associations with psychotropic medication load. Bipolar Disord 2008; 10:916-27. [PMID: 19594507 PMCID: PMC2711546 DOI: 10.1111/j.1399-5618.2008.00641.x] [Citation(s) in RCA: 208] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
OBJECTIVE To examine abnormal patterns of frontal cortical-subcortical activity in response to emotional stimuli in euthymic individuals with bipolar disorder type I in order to identify trait-like, pathophysiologic mechanisms of the disorder. We examined potential confounding effects of total psychotropic medication load and illness variables upon neural abnormalities. METHOD We analyzed neural activity in 19 euthymic bipolar and 24 healthy individuals to mild and intense happy, fearful and neutral faces. RESULTS Relative to healthy individuals, bipolar subjects had significantly increased left striatal activity in response to mild happy faces (p < 0.05, corrected), decreased right dorsolateral prefrontal cortical (DLPFC) activity in response to neutral, mild and intense happy faces, and decreased left DLPFC activity in response to neutral, mild and intense fearful faces (p < 0.05, corrected). Bipolar and healthy individuals did not differ in amygdala activity in response to either emotion. In bipolar individuals, there was no significant association between medication load and abnormal activity in these regions, but a negative relationship between age of illness onset and amygdala activity in response to mild fearful faces (p = 0.007). Relative to those without comorbidities, bipolar individuals with comorbidities showed a trend increase in left striatal activity in response to mild happy faces. CONCLUSIONS Abnormally increased striatal activity in response to potentially rewarding stimuli and decreased DLPFC activity in response to other emotionally salient stimuli may underlie mood instabilities in euthymic bipolar individuals, and are more apparent in those with comorbid diagnoses. No relationship between medication load and abnormal neural activity in bipolar individuals suggests that our findings may reflect pathophysiologic mechanisms of the illness rather than medication confounds. Future studies should examine whether this pattern of abnormal neural activity could distinguish bipolar from unipolar depression.
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Research Support, N.I.H., Extramural |
17 |
208 |
16
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Park SB, Coull JT, McShane RH, Young AH, Sahakian BJ, Robbins TW, Cowen PJ. Tryptophan depletion in normal volunteers produces selective impairments in learning and memory. Neuropharmacology 1994; 33:575-88. [PMID: 7984295 DOI: 10.1016/0028-3908(94)90089-2] [Citation(s) in RCA: 201] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
The amino-acid L-tryptophan is essential in the synthesis of brain serotonin, and its depletion can lead to a widespread reduction in central serotonergic activity. A placebo-controlled cross-over within-subjects design (n = 12) examined the effects of tryptophan depletion on human cognitive performance. A low-tryptophan (low-TRP) drink successfully reduced the levels of plasma and total free tryptophan. Computerized tests of memory, learning and executive function revealed selective and non-sedative impairments on cognitive performance following the active drink. Specifically, low-TRP impaired learning as seen in tests of visual discrimination and paired associates. Furthermore, low-TRP lengthened thinking times during the Tower of London planning task, but only in subjects already familiar with the task, suggesting a retrieval deficit. No evidence was found for an effect of the low-TRP drink on measures sensitive to frontal lobe dysfunction, supporting instead a specific role for the serotonergic system in the processes of memory and learning not directly implicated in frontal lobe function.
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Clinical Trial |
31 |
201 |
17
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Liddle EB, Hollis C, Batty MJ, Groom MJ, Totman JJ, Liotti M, Scerif G, Liddle PF. Task-related default mode network modulation and inhibitory control in ADHD: effects of motivation and methylphenidate. J Child Psychol Psychiatry 2011; 52:761-71. [PMID: 21073458 PMCID: PMC4754961 DOI: 10.1111/j.1469-7610.2010.02333.x] [Citation(s) in RCA: 199] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND Deficits characteristic of attention deficit/hyperactivity disorder (ADHD), including poor attention and inhibitory control, are at least partially alleviated by factors that increase engagement of attention, suggesting a hypodopaminergic reward deficit. Lapses of attention are associated with attenuated deactivation of the default mode network (DMN), a distributed brain system normally deactivated during tasks requiring attention to the external world. Task-related DMN deactivation has been shown to be attenuated in ADHD relative to controls. We hypothesised that motivational incentives to balance speed against restraint would increase task engagement during an inhibitory control task, enhancing DMN deactivation in ADHD. We also hypothesised that methylphenidate, an indirect dopamine agonist, would tend to normalise abnormal patterns of DMN deactivation. METHOD We obtained functional magnetic resonance images from 18 methylphenidate-responsive children with ADHD (DSM-IV combined subtype) and 18 pairwise-matched typically developing children aged 9-15 years while they performed a paced Go/No-go task. We manipulated motivational incentive to balance response speed against inhibitory control, and tested children with ADHD both on and off methylphenidate. RESULTS When children with ADHD were off-methylphenidate and task incentive was low, event-related DMN deactivation was significantly attenuated compared to controls, but the two groups did not differ under high motivational incentives. The modulation of DMN deactivation by incentive in the children with ADHD, off-methylphenidate, was statistically significant, and significantly greater than in typically developing children. When children with ADHD were on-methylphenidate, motivational modulation of event-related DMN deactivation was abolished, and no attenuation relative to their typically developing peers was apparent in either motivational condition. CONCLUSIONS During an inhibitory control task, children with ADHD exhibit a raised motivational threshold at which task-relevant stimuli become sufficiently salient to deactivate the DMN. Treatment with methylphenidate normalises this threshold, rendering their pattern of task-related DMN deactivation indistinguishable from that of typically developing children.
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research-article |
14 |
199 |
18
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Goudriaan AE, de Ruiter MB, van den Brink W, Oosterlaan J, Veltman DJ. Brain activation patterns associated with cue reactivity and craving in abstinent problem gamblers, heavy smokers and healthy controls: an fMRI study. Addict Biol 2010; 15:491-503. [PMID: 20840335 PMCID: PMC3014110 DOI: 10.1111/j.1369-1600.2010.00242.x] [Citation(s) in RCA: 195] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Abnormal cue reactivity is a central characteristic of addiction, associated with increased activity in motivation, attention and memory related brain circuits. In this neuroimaging study, cue reactivity in problem gamblers (PRG) was compared with cue reactivity in heavy smokers (HSM) and healthy controls (HC). A functional magnetic resonance imaging event-related cue reactivity paradigm, consisting of gambling, smoking-related and neutral pictures, was employed in 17 treatment-seeking non-smoking PRG, 18 non-gambling HSM, and 17 non-gambling and non-smoking HC. Watching gambling pictures (relative to neutral pictures) was associated with higher brain activation in occipitotemporal areas, posterior cingulate cortex, parahippocampal gyrus and amygdala in PRG compared with HC and HSM. Subjective craving in PRG correlated positively with brain activation in left ventrolateral prefrontal cortex and left insula. When comparing the HSM group with the two other groups, no significant differences in brain activity induced by smoking cues were found. In a stratified analysis, the HSM subgroup with higher Fagerström Test for Nicotine Dependence scores (FTND M = 5.4) showed higher brain activation in ventromedial prefrontal cortex, rostral anterior cingulate cortex, insula and middle/superior temporal gyrus while watching smoking-related pictures (relative to neutral pictures) than the HSM subgroup with lower FTND scores (FTND M = 2.9) and than non-smoking HC. Nicotine craving correlated with activation in left prefrontal and left amygdala when viewing smoking-related pictures in HSM. Increased regional responsiveness to gambling pictures in brain regions linked to motivation and visual processing is present in PRG, similar to neural mechanisms underlying cue reactivity in substance dependence. Increased brain activation in related fronto-limbic brain areas was present in HSM with higher FTND scores compared with HSM with lower FTND scores.
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Research Support, Non-U.S. Gov't |
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Field M, Mogg K, Zetteler J, Bradley BP. Attentional biases for alcohol cues in heavy and light social drinkers: the roles of initial orienting and maintained attention. Psychopharmacology (Berl) 2004; 176:88-93. [PMID: 15071718 DOI: 10.1007/s00213-004-1855-1] [Citation(s) in RCA: 193] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/18/2003] [Accepted: 02/18/2004] [Indexed: 10/26/2022]
Abstract
RATIONALE There has been considerable theoretical interest in attentional biases for drug-related cues. However, there is little research on the component processes of such attentional biases. OBJECTIVES We examined initial orienting to, and the maintenance of attention on, alcohol-related cues in heavy and light social drinkers. METHODS The present study used a visual probe task to investigate biases in visual orienting to alcohol-related cues. We varied the presentation duration of alcohol-related pictures (200, 500 or 2000 ms) to investigate whether attentional biases operated in initial orienting or the maintenance of attention. RESULTS In comparison with light social drinkers, heavy social drinkers had an attentional bias for alcohol pictures which were presented at the longer exposure durations (500 and 2000 ms), but not at the shorter duration of 200 ms. Subjective alcohol craving was correlated with the attentional bias index for alcohol pictures presented for 2000 ms. CONCLUSIONS These results suggest that biases in visual orienting to alcohol-related cues in heavy social drinkers operate mainly in the processes involved in the maintenance of attention.
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Comparative Study |
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Tannock R, Schachar RJ, Carr RP, Chajczyk D, Logan GD. Effects of methylphenidate on inhibitory control in hyperactive children. JOURNAL OF ABNORMAL CHILD PSYCHOLOGY 1989; 17:473-91. [PMID: 2681316 DOI: 10.1007/bf00916508] [Citation(s) in RCA: 187] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
This study investigated the effects of methylphenidate (MPH) on inhibitory control in hyperactive children. A double-blind, placebo-control, within-subject (crossover) design was used in which 12 children, between 6 and 11 years of age, were each tested four times in each drug condition: 0.3 mg/kg and 1.0 mg/kg of methylphenidate, and placebo. Dependent measures included (a) the probability of inhibiting responses to a primary choice reaction time task given a stop signal, on the Stopping Task, and (b) response latency and errors on the Matching Familiar Figures Test (MFFT). MPH improved the efficiency of the central inhibitory mechanism by speeding the inhibitory process, thereby affording the children greater control over their actions and enabling them to increase the probability with which they inhibited responses given a stop signal. MPH increased response latency but did not reduce errors on the MFFT, and observation of the children's task performance highlighted the interpretive problems associated with this task. Performance on both tasks was better at a dosage of 1.0 mg/kg than at 0.3 mg/kg.
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Clinical Trial |
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187 |
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Roy AK, Vasa RA, Bruck M, Mogg K, Bradley BP, Sweeney M, Bergman RL, McClure-Tone EB, Pine DS, CAMS Team. Attention bias toward threat in pediatric anxiety disorders. J Am Acad Child Adolesc Psychiatry 2008; 47:1189-96. [PMID: 18698266 PMCID: PMC2783849 DOI: 10.1097/chi.0b013e3181825ace] [Citation(s) in RCA: 178] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Collaborators] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To examine attention bias toward threat faces in a large sample of anxiety-disordered youths using a well-established visual probe task. METHOD Study participants included 101 children and adolescents (ages 7-18 years) with generalized anxiety disorder, social phobia, and/or separation anxiety disorder enrolled in a multisite anxiety treatment study. Nonanxious youths (n = 51; ages 9-18 years) were recruited separately. Participants were administered a computerized visual probe task that presents pairs of faces portraying threat (angry), positive (happy), and neutral expressions. They pressed a response key to indicate the spatial location of a probe that replaced one of the faces on each trial. Attention bias scores were calculated from response times to probes for each emotional face type. RESULTS Compared to healthy youths, anxious participants demonstrated a greater attention bias toward threat faces. This threat bias in anxious patients did not significantly vary across the anxiety disorders. There was no group difference in attention bias toward happy faces. CONCLUSIONS These results suggest that pediatric anxiety disorders are associated with an attention bias toward threat. Future research may examine the manner in which cognitive bias in anxious youths changes with treatment.
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Collaborators
John T Walkup, Golda S Ginsburg, Anne Marie Albano, Bruce Waslick, Boris Birmaher, Dara Sakolsky, Satish Iyengar, Philip C Kendall, Moira Rynn, John S March, Scott N Compton, John Piacentini, Jim McCracken, Scott N Compton, Joel Sherrill,
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Multicenter Study |
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178 |
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Schneider JS, Kovelowski CJ. Chronic exposure to low doses of MPTP. I. Cognitive deficits in motor asymptomatic monkeys. Brain Res 1990; 519:122-8. [PMID: 2397401 DOI: 10.1016/0006-8993(90)90069-n] [Citation(s) in RCA: 176] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Cognitive deficits which may occur following chronic low-dose exposure to 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) were studied in monkeys who remained motor asymptomatic for parkinsonism throughout the study. The tasks used to assess cognitive functioning are those which have proved in the past to be sensitive to disruption of frontal cortical and or striatal integrity (delayed response and delayed alternation) or sensitive to inferior temporal lobe dysfunction (visual pattern discrimination). Since Parkinson's disease patients have been described as exhibiting frontal signs, we were interested to examine whether MPTP-treated monkeys might exhibit deficits on frontally-mediated tasks, without the confound of motor disturbances. We found that macaque nemistrina monkeys exposed to cumulative doses of 14.94-75.42 mg of MPTP over periods ranging from 5 to 13 months never developed parkinsonian motor signs. However, all 4 animals examined showed significant post-MPTP deficits in delayed response and delayed alternation performance, while visual pattern discrimination performance remained intact. These animals also developed other behavioral problems including irritability and decreased attentiveness. These results show that MPTP can cause specific cognitive deficits independent of the motor deficits which can be produced by this toxin.
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Prickaerts J, van Staveren WCG, Sik A, Markerink-van Ittersum M, Niewöhner U, van der Staay FJ, Blokland A, de Vente J. Effects of two selective phosphodiesterase type 5 inhibitors, sildenafil and vardenafil, on object recognition memory and hippocampal cyclic GMP levels in the rat. Neuroscience 2002; 113:351-61. [PMID: 12127092 DOI: 10.1016/s0306-4522(02)00199-9] [Citation(s) in RCA: 176] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The present study investigated the effects of two cyclic GMP-specific phosphodiesterase enzyme type 5 inhibitors, sildenafil and vardenafil, on the memory performance in the object recognition task. Both compounds were given per orally (1, 3 and 10 mg/kg sildenafil; 0.1, 0.3, 1 and 3 mg/kg vardenafil) immediately after the exposure to two identical objects. The memory for the objects was tested 24 h later. Vehicle-treated rats spent equal times exploring a new and the familiar object demonstrating that they did not remember the familiar one. However, sildenafil improved the object discrimination performance of the rats with a high discrimination performance at a dose of 3 mg/kg. Rats treated with vardenafil also showed an improved object discrimination performance. Compared with sildenafil, vardenafil appeared to be even more potent in this respect since it already produced a high discrimination performance at a dose of 0.3 mg/kg. The effects of both compounds on cyclic GMP and cyclic AMP accumulation were studied in rat hippocampal slices incubated in vitro. Cyclic GMP levels were increased after incubation with the highest concentration of 100 microM vardenafil (together with 0.1 mM sodium nitroprusside), although no changes in cyclic GMP levels were detected after incubation with different concentrations of sildenafil. Both compounds had no effect on cyclic AMP levels. Additional cyclic GMP immunocytochemistry showed that incubation with vardenafil (in the presence of sodium nitroprusside) resulted in a concentration-dependent staining of cyclic GMP. Staining was predominantly found in neuronal fibres in the hippocampal CA2/CA3 region. It was already detected at a concentration of 0.1 microM vardenafil. Also positive fibres were detected after incubation with sildenafil but at a higher concentration of 10 microM. Taken together, these results suggest that inhibition of phosphodiesterase enzyme type 5 improves object recognition memory. This effect might be explained by increased levels of central cyclic GMP.
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Seigers R, Schagen SB, Beerling W, Boogerd W, van Tellingen O, van Dam FSAM, Koolhaas JM, Buwalda B. Long-lasting suppression of hippocampal cell proliferation and impaired cognitive performance by methotrexate in the rat. Behav Brain Res 2008; 186:168-75. [PMID: 17854921 DOI: 10.1016/j.bbr.2007.08.004] [Citation(s) in RCA: 176] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2007] [Revised: 08/02/2007] [Accepted: 08/06/2007] [Indexed: 11/19/2022]
Abstract
Methotrexate (MTX) is a cytostatic agent widely used in combination with other agents as adjuvant chemotherapy for breast cancer and is associated with cognitive impairment as a long-term side effect in some cancer patients. This paper aimed to identify a neurobiological mechanism possibly responsible for this cognitive impairment using an animal model. The first study explored the hypothesis that MTX reduces neuronal cell proliferation. A dose-dependent long-lasting decrease in hippocampal cell proliferation was shown with Ki-67 immunocytochemistry, following a single intravenous injection of MTX (37.5-300 mg/kg). Animals treated with MTX also showed a dose-dependent transient decrease in body weight gain. In the second study, the effect of MTX (250 mg/kg) on two spatial learning tasks was examined. Animals treated with MTX learned the Morris water maze task adequately; however, these animals showed a longer latency time to cross the platform location in the probe trial, reflecting an impairment of spatial memory function. In the novel object recognition task, animals treated with MTX failed to distinguish a novel object from a familiar one, indicating a decrease in the comparator function of the hippocampus. Our studies indicated that, in the rat, MTX has a dose-dependent negative effect on hippocampal cell proliferation, and on cognitive behavior. These findings suggest that adverse effects of certain cytotoxic agents on hippocampal cell proliferation may have a potential contributory role in cognitive impairment observed in humans after chemotherapy.
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Sahakian BJ, Owen AM, Morant NJ, Eagger SA, Boddington S, Crayton L, Crockford HA, Crooks M, Hill K, Levy R. Further analysis of the cognitive effects of tetrahydroaminoacridine (THA) in Alzheimer's disease: assessment of attentional and mnemonic function using CANTAB. Psychopharmacology (Berl) 1993; 110:395-401. [PMID: 7870908 DOI: 10.1007/bf02244644] [Citation(s) in RCA: 171] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Results of a placebo controlled cross-over trial (N = 89) of the anticholinesterase drug THA as a treatment for dementia of the Alzheimer's type (DAT) are reported, with reference to previous trials of the drug and the cholinergic hypothesis of aging and dementia. Using computerised tests sensitive to specific aspects of memory and attention, evidence is found for improvements in attentional function rather than memory, in patients with mild to moderate DAT. Although these improvements were significant, they were small and restricted to certain tests of attentional function. Nevertheless, they add to the growing body of evidence that the cholinergic system is involved in the control of attentional processes. The results will be relevant to future investigations into the therapeutic effects of enhancement of the cholinergic system in DAT sufferers.
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Clinical Trial |
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171 |