1
|
Eckert M, Scherenberg V, Klinke C. How a token-based game may elicit the reward prediction error and increase engagement of students in elementary school. A pilot study. Front Psychol 2023; 14:1077406. [PMID: 37089735 PMCID: PMC10116860 DOI: 10.3389/fpsyg.2023.1077406] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2022] [Accepted: 02/24/2023] [Indexed: 04/09/2023] Open
Abstract
Student engagement is essential to academic success and student-wellbeing. In the past, fostering engagement though extrinsic rewards has often been found to be of limited effectiveness over the long term. However, extrinsic rewards are important for improving engagement with non-intrinsically rewarding activities. Thus, in the present study a mechanism that is meant to prolong the effects of extrinsic rewards was investigated: the reward prediction error. This error occurs when rewards are awarded contrary to the awardee’s expectations. In a quasi-experiment, 39 elementary school students participated in a classroom-based game, which was supposed to motivate them to solve math exercises. It combined reinforcement with elements of luck, which were supposed to elicit the reward prediction error. After 2 weeks, the intervention group had completed significantly more math exercises compared to a pretest and, importantly, also more correctly solved exercises than a control group. This suggests that game-based reinforcement that elicits the reward prediction error might help to increase student engagement over the medium term. It furthermore highlights the importance of applying gamification elements not only digitally but also in analog settings.
Collapse
Affiliation(s)
- Marcus Eckert
- Department of Psychology and Pedagogy, Apollon University of Applied Sciences, Bremen, Germany
- *Correspondence: Marcus Eckert,
| | - Viviane Scherenberg
- Department of Public Health and Environmental Health, Apollon University of Applied Sciences, Bremen, Germany
| | - Clemens Klinke
- Department of Psychology and Pedagogy, Apollon University of Applied Sciences, Bremen, Germany
| |
Collapse
|
2
|
Chiu CH, Weng SJ, Yeh SHH, Jhao YT, Chang HF, Huang WS, Cheng CY, Yeh CC, Ma KH. Assessment of the anti-nociceptive effects of fetal ventral mesencephalic tissue allografts in a rat model of hemi-Parkinson's disease using fMRI. Front Aging Neurosci 2022; 14:948848. [PMID: 36466604 PMCID: PMC9716198 DOI: 10.3389/fnagi.2022.948848] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Accepted: 10/17/2022] [Indexed: 12/04/2023] Open
Abstract
Extensive studies showed increased subjective pain sensitivity in Parkinson's disease (PD), which appeared to be partially reversed by dopaminergic (DA) treatment. Although cell replacement represents an attractive therapeutic strategy, its potential for PD-related hyperalgesia remains unclear. We investigated re-establishment of DA function via allografting exogenic DA cells on pain hypersensitivity in a rat model of PD. We evaluated the anti-nociceptive effects of fetal ventral mesencephalic (rVM) tissue allografts in PD rats after unilateral 6-OHDA-induced toxicity in the medial forebrain bundle. The drug -induced rotation test was used to validate the severity of the nigrostriatal lesion; von Frey and thermal pain tests were employed to evaluate nociceptive function. Nociception-induced cerebral blood volume (CBV) response was measured using a 4.7-T MR system. Finally, the immunohistochemical (IHC) studies were performed and the results were compared with the imaging findings from functional magnetic resonance imaging (fMRI). The grafts significantly improved drug-induced rotation behavior and increased mechanical and thermal nociceptive thresholds in PD rats. The elevation of CBV signals significantly recovered on the grafted striatum, whereas this effect was inhibited by the D2R antagonist eticlopride in each striatum. Quantitative IHC analysis revealed the transplantation markedly increased the numbers of tyrosine hydroxylase immunoreactive cells. Therefore, we concluded transplantation of rVM tissue results in anti-nociceptive effects and improves motor function. Moreover, in vivo CBV response confirmed the key role of D2R-mediated pain modulation. Therefore, we demonstrate fMRI as a reliable imaging index in evaluating the anti-nociceptive therapeutic effects of fetal rVM transplantation in the rat model of PD.
Collapse
Affiliation(s)
- Chuang-Hsin Chiu
- Department of Nuclear Medicine, National Defense Medical Center, Tri-Service General Hospital, Taipei, Taiwan
| | - Shao-Ju Weng
- Department of Biology and Anatomy, National Defense Medical Center, Taipei, Taiwan
| | | | - Yun-Ting Jhao
- Department of Biology and Anatomy, National Defense Medical Center, Taipei, Taiwan
| | | | - Wen-Sheng Huang
- Department of Nuclear Medicine, Cheng-Hsin General Hospital, Taipei, Taiwan
| | - Cheng-Yi Cheng
- Department of Nuclear Medicine, National Defense Medical Center, Tri-Service General Hospital, Taipei, Taiwan
| | - Chun-Chang Yeh
- Department of Anesthesiology, National Defense Medical Center, Tri-Service General Hospital, Taipei, Taiwan
| | - Kuo-Hsing Ma
- Department of Biology and Anatomy, National Defense Medical Center, Taipei, Taiwan
| |
Collapse
|
3
|
Yuan JP, Connolly CG, Henje E, Sugrue LP, Yang TT, Xu D, Tymofiyeva O. Gray Matter Changes in Adolescents Participating in a Meditation Training. Front Hum Neurosci 2020; 14:319. [PMID: 32922278 PMCID: PMC7456888 DOI: 10.3389/fnhum.2020.00319] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2020] [Accepted: 07/17/2020] [Indexed: 12/11/2022] Open
Abstract
Meditation has shown to benefit a wide range of conditions and symptoms, but the neural mechanisms underlying the practice remain unclear. Magnetic resonance imaging (MRI) studies have investigated the structural brain changes due to the practice by examining volume, density, or cortical thickness changes. However, these studies have focused on adults; meditation’s structural effects on the adolescent brain remain understudied. In this study, we investigated how meditation training affects the structure of the adolescent brain by scanning a group of 38 adolescents (16.48 ± 1.29 years) before and after participating in a 12-week meditation training. Subjects underwent Training for Awareness, Resilience, and Action (TARA), a program that mainly incorporates elements from mindfulness meditation and yoga-based practices. A subset of the adolescents also received an additional control scan 12 weeks before TARA. We conducted voxel-based morphometry (VBM) to assess gray matter volume changes pre- to post-training and during the control period. Subjects showed significant gray matter (GM) volume decreases in the left posterior insula and to a lesser extent in the left thalamus and left putamen after meditation training. There were no significant changes during the control period. Our results support previous findings that meditation affects regions associated with physical and emotional awareness. However, our results are different from previous morphometric studies in which meditation was associated with structural increases. We posit that this discrepancy may be due to the differences between the adolescent brain and the adult brain.
Collapse
Affiliation(s)
- Justin P Yuan
- Department of Radiology & Biomedical Imaging, University of California, San Francisco, San Francisco, CA, United States.,Department of Psychology, Stanford University, Stanford, CA, United States
| | - Colm G Connolly
- Department of Biomedical Sciences, Florida State University College of Medicine, Tallahassee, FL, United States
| | - Eva Henje
- Department of Psychiatry and Behavioral Sciences, The Langley Porter Psychiatric Institute, Division of Child and Adolescent Psychiatry, Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, United States.,Department of Clinical Science/Child and Adolescent Psychiatry, Umeå University, Umeå, Sweden
| | - Leo P Sugrue
- Department of Radiology & Biomedical Imaging, University of California, San Francisco, San Francisco, CA, United States
| | - Tony T Yang
- Department of Psychiatry and Behavioral Sciences, The Langley Porter Psychiatric Institute, Division of Child and Adolescent Psychiatry, Weill Institute for Neurosciences, University of California, San Francisco, San Francisco, CA, United States
| | - Duan Xu
- Department of Radiology & Biomedical Imaging, University of California, San Francisco, San Francisco, CA, United States
| | - Olga Tymofiyeva
- Department of Radiology & Biomedical Imaging, University of California, San Francisco, San Francisco, CA, United States
| |
Collapse
|
4
|
Marquie M, Locascio JJ, Rentz DM, Becker JA, Hedden T, Johnson KA, Growdon JH, Gomperts SN. Striatal and extrastriatal dopamine transporter levels relate to cognition in Lewy body diseases: an (11)C altropane positron emission tomography study. ALZHEIMERS RESEARCH & THERAPY 2014; 6:52. [PMID: 25429309 PMCID: PMC4245149 DOI: 10.1186/s13195-014-0052-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/20/2014] [Accepted: 07/25/2014] [Indexed: 02/06/2023]
Abstract
Introduction The biological basis of cognitive impairment in parkinsonian diseases is believed to be multifactorial. We investigated the contribution of dopamine deficiency to cognition in Parkinson disease (PD) and dementia with Lewy bodies (DLB) with dopamine transporter (DAT) imaging. Methods We acquired 11C altropane PET, magnetic resonance imaging and cognitive testing in 19 nondemented subjects with PD, 10 DLB and 17 healthy control subjects (HCS). We analyzed DAT concentration in putamen, caudate, anterior cingulate (AC), orbitofrontal and prefrontal regions, using the Standardized Uptake Volume Ratio with partial volume correction, and we related DAT concentration and global cortical thickness to neuropsychological performance. Results DAT concentration in putamen and in caudate were similar in PD and DLB groups and significantly lower than in HCS. Reduced caudate DAT concentration was associated with worse Clinical Dementia Rating Scale–sum of boxes (CDR-SB) scores and visuospatial skills in DLB but not in PD or HCS groups. Adjusting for putamen DAT concentration, as a measure of severity of motor disease, caudate DAT concentration was lower in DLB than in PD. Higher AC DAT concentration was associated with lower putamen DAT concentration in DLB and with higher putamen DAT concentration in PD. Higher AC DAT concentration in DLB correlated with greater impairment in semantic memory and language. Conclusions Caudate and AC dopamine dysfunction contribute in opposing directions to cognitive impairment in DLB.
Collapse
Affiliation(s)
- Marta Marquie
- Department of Neurology, Massachusetts General Hospital, 15 Parkman St., Boston, MA 02114 USA ; MassGeneral Institute for Neurodegenerative Disease, 16th St., Building 114, Charlestown Navy Yard, Charlestown, MA 02129 USA ; Autonomous University of Barcelona, Medicine Doctoral Studies, Doctoral School, U Building, Autonomous University of Barcelona Campus, Bellaterra (Cerdanyola del Valles), 08193 Spain
| | - Joseph J Locascio
- Department of Neurology, Massachusetts General Hospital, 15 Parkman St., Boston, MA 02114 USA
| | - Dorene M Rentz
- Department of Neurology, Massachusetts General Hospital, 15 Parkman St., Boston, MA 02114 USA ; Department of Neurology, Brigham and Women's Hospital, 221 Longwood Avenue, Boston, MA 02115 USA
| | - J Alex Becker
- Department of Radiology, Massachusetts General Hospital, 55 Fruit St., Boston, MA 02114 USA
| | - Trey Hedden
- Department of Radiology, Massachusetts General Hospital, 55 Fruit St., Boston, MA 02114 USA ; Athinoula A. Martinos Center for Biomedical Imaging, 13th St., Building 149, Charlestown Navy Yard, Charlestown, MA 02129 USA
| | - Keith A Johnson
- Department of Neurology, Massachusetts General Hospital, 15 Parkman St., Boston, MA 02114 USA ; Department of Radiology, Massachusetts General Hospital, 55 Fruit St., Boston, MA 02114 USA
| | - John H Growdon
- Department of Neurology, Massachusetts General Hospital, 15 Parkman St., Boston, MA 02114 USA
| | - Stephen N Gomperts
- Department of Neurology, Massachusetts General Hospital, 15 Parkman St., Boston, MA 02114 USA ; MassGeneral Institute for Neurodegenerative Disease, 16th St., Building 114, Charlestown Navy Yard, Charlestown, MA 02129 USA
| |
Collapse
|
5
|
Staller JA, Faraone SV. Targeting the dopamine system in the treatment of attention-deficit/hyperactivity disorder. Expert Rev Neurother 2014; 7:351-62. [PMID: 17425490 DOI: 10.1586/14737175.7.4.351] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Attention-deficit/hyperactivity disorder (ADHD) is a highly heritable condition that affects a significant number of children and adults worldwide. During the past 30 years, the diagnosis and treatment of ADHD has relied on clinical assessment and empirical experience with stimulant medications. More recently, advances in family genetic studies, molecular genetic studies, preclinical research, radiographic imaging techniques and neuropsychological evaluation have significantly enhanced our understanding of the neurobiology of ADHD. This review highlights the current central role of dopamine in the pathophysiology and treatment of ADHD and implications for future advances in diagnosis and treatment.
Collapse
Affiliation(s)
- Jud A Staller
- Division of Child & Adolescent Psychiatry, SUNY Upstate Medical University, Syracuse, NY 13210, USA.
| | | |
Collapse
|
6
|
Suoranta S, Holli-Helenius K, Koskenkorva P, Niskanen E, Könönen M, Äikiä M, Eskola H, Kälviäinen R, Vanninen R. 3D texture analysis reveals imperceptible MRI textural alterations in the thalamus and putamen in progressive myoclonic epilepsy type 1, EPM1. PLoS One 2013; 8:e69905. [PMID: 23922849 PMCID: PMC3726751 DOI: 10.1371/journal.pone.0069905] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2013] [Accepted: 06/12/2013] [Indexed: 01/22/2023] Open
Abstract
Progressive myoclonic epilepsy type 1 (EPM1) is an autosomal recessively inherited neurodegenerative disorder characterized by young onset age, myoclonus and tonic-clonic epileptic seizures. At the time of diagnosis, the visual assessment of the brain MRI is usually normal, with no major changes found later. Therefore, we utilized texture analysis (TA) to characterize and classify the underlying properties of the affected brain tissue by means of 3D texture features. Sixteen genetically verified patients with EPM1 and 16 healthy controls were included in the study. TA was performed upon 3D volumes of interest that were placed bilaterally in the thalamus, amygdala, hippocampus, caudate nucleus and putamen. Compared to the healthy controls, EPM1 patients had significant textural differences especially in the thalamus and right putamen. The most significantly differing texture features included parameters that measure the complexity and heterogeneity of the tissue, such as the co-occurrence matrix-based entropy and angular second moment, and also the run-length matrix-based parameters of gray-level non-uniformity, short run emphasis and long run emphasis. This study demonstrates the usability of 3D TA for extracting additional information from MR images. Textural alterations which suggest complex, coarse and heterogeneous appearance were found bilaterally in the thalamus, supporting the previous literature on thalamic pathology in EPM1. The observed putamenal involvement is a novel finding. Our results encourage further studies on the clinical applications, feasibility, reproducibility and reliability of 3D TA.
Collapse
Affiliation(s)
- Sanna Suoranta
- Department of Clinical Radiology, Kuopio University Hospital, Kuopio, Finland.
| | | | | | | | | | | | | | | | | |
Collapse
|
7
|
Passamonti L, Salsone M, Toschi N, Cerasa A, Giannelli M, Chiriaco C, Cascini GL, Fera F, Quattrone A. Dopamine-transporter levels drive striatal responses to apomorphine in Parkinson's disease. Brain Behav 2013; 3:249-62. [PMID: 23785657 PMCID: PMC3683285 DOI: 10.1002/brb3.115] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/24/2012] [Revised: 11/15/2012] [Accepted: 11/30/2012] [Indexed: 11/21/2022] Open
Abstract
Dopaminergic therapy in Parkinson's disease (PD) can improve some cognitive functions while worsening others. These opposite effects might reflect different levels of residual dopamine in distinct parts of the striatum, although the underlying mechanisms remain poorly understood. We used functional magnetic resonance imaging (fMRI) to address how apomorphine, a potent dopamine agonist, influences brain activity associated with working memory in PD patients with variable levels of nigrostriatal degeneration, as assessed via dopamine-transporter (DAT) scan. Twelve PD patients underwent two fMRI sessions (Off-, On-apomorphine) and one DAT-scan session. Twelve sex-, age-, and education-matched healthy controls underwent one fMRI session. The core fMRI analyses explored: (1) the main effect of group; (2) the main effect of treatment; and (3) linear and nonlinear interactions between treatment and DAT levels. Relative to controls, PD-Off patients showed greater activations within posterior attentional regions (e.g., precuneus). PD-On versus PD-Off patients displayed reduced left superior frontal gyrus activation and enhanced striatal activation during working-memory task. The relation between DAT levels and striatal responses to apomorphine followed an inverted-U-shaped model (i.e., the apomorphine effect on striatal activity in PD patients with intermediate DAT levels was opposite to that observed in PD patients with higher and lower DAT levels). Previous research in PD demonstrated that the nigrostriatal degeneration (tracked via DAT scan) is associated with inverted-U-shaped rearrangements of postsynaptic D2-receptors sensitivity. Hence, it can be hypothesized that individual differences in DAT levels drove striatal responses to apomorphine via D2-receptor-mediated mechanisms.
Collapse
Affiliation(s)
- Luca Passamonti
- Istituto di Scienze Neurologiche (ISN), Consiglio Nazionale delle Ricerche 88100, Catanzaro, Italia ; Dipartimento di Scienze Mediche e Chirurgiche, Università degli Studi "Magna Graecia" 88100, Catanzaro, Italia
| | | | | | | | | | | | | | | | | |
Collapse
|
8
|
Martín A, Gómez-Vallejo V, San Sebastián E, Padró D, Markuerkiaga I, Llarena I, Llop J. In vivo imaging of dopaminergic neurotransmission after transient focal ischemia in rats. J Cereb Blood Flow Metab 2013; 33:244-52. [PMID: 23149560 PMCID: PMC3564194 DOI: 10.1038/jcbfm.2012.162] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The precise biologic mechanisms involved in functional recovery processes in response to stroke such as dopaminergic neurotransmission are still largely unknown. For this purpose, we performed in parallel in vivo magnetic resonance imaging and positron emission tomography (PET) with [(18)F]fluorodeoxyglucose ([(18)F]FDG) and [(11)C]raclopride at 1, 3, 7, 14, 21, and 28 days after middle cerebral artery occlusion in rats. In the ischemic territory, PET [(18)F]FDG showed a initial decrease in cerebral metabolism followed by a time-dependent recovery to quasi-normal values at day 14 after ischemia. The PET with [(11)C]raclopride, a ligand for dopamine D(2) receptor, showed a sustained binding during the first week after ischemia that declined dramatically from day 14 to day 28. Interestingly, a slight increase in [(11)C]raclopride binding was observed at days 1 to 3 followed by the uppermost binding at day 7 in the contralateral territory. Likewise, in vitro autoradiography using [(3)H]raclopride confirmed these in vivo results. Finally, the neurologic test showed major neurologic impairment at day 1 followed by a recovery of the cerebral function at day 28 after cerebral ischemia. Taken together, these results might suggest that dopamine D(2) receptor changes in the contralateral hemisphere could have a key role in functional recovery after cerebral ischemia.
Collapse
Affiliation(s)
- Abraham Martín
- Molecular Imaging Unit, CIC biomaGUNE, San Sebastián, Spain.
| | | | | | | | | | | | | |
Collapse
|
9
|
Teicher MH, Polcari A, Fourligas N, Vitaliano G, Navalta CP. Hyperactivity persists in male and female adults with ADHD and remains a highly discriminative feature of the disorder: a case-control study. BMC Psychiatry 2012; 12:190. [PMID: 23134619 PMCID: PMC3560176 DOI: 10.1186/1471-244x-12-190] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2012] [Accepted: 10/12/2012] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Symptoms of hyperactivity are believed to fade with age leaving ADHD adults mostly inattentive and impulsive. Our aim was to test this assertion using objective measures of hyperactivity, impulsivity and inattention. METHOD Participants were 40 subjects with ADHD (23M/17F; 35±10 yrs) and 60 healthy adults (28M/32F; 29±9 yrs) blindly assessed using Wender-Reimherr interview ratings, Structured Clinical Interview for DSM-IV Disorders and DSM-IV criteria. Infrared motion capture systems tracked head and leg movements during performance of a No-4's cognitive control task. Subjects also completed the Conners' CPT-II. RESULTS ADHD and controls differed significantly in activity and attention. Effect sizes for activity measures (d' = 0.7-1.6) were, on average, two-fold larger than differences in attention or impulsivity, correlated more strongly with executive function ratings and were more discriminatory (ROC area = 0.83 for activity composite, 0.65 for No-4's distraction composite, 0.63 for Conners' CPT-II confidence index, 0.96 for the combined activity and attention diagnostic index). This finding was true for subjects with the predominantly inattentive subtype as well as subjects with combined or predominantly hyperactive/impulsive subtype. Males and females with ADHD were equally active. The superior accuracy of activity measures was confirmed using Random Forest and predictive modeling techniques. CONCLUSIONS Objectively measured hyperactivity persists in adults with ADHD and is a more discriminative feature of the disorder than computerized measures of inattention or impulsivity. This finding supports the hypothesis that a deficient ability to sit still remains a defining feature of the disorder in adults when it is measured objectively.
Collapse
Affiliation(s)
- Martin H Teicher
- Developmental Biopsychiatry Research Program, McLean Hospital, 115 Mill Street, Belmont, MA 02478, USA.
| | - Ann Polcari
- Developmental Biopsychiatry Research Program, McLean Hospital, 115 Mill Street, Belmont, MA, 02478, USA,Department of Psychiatry, Harvard Medical School, Boston, MA, USA,School of Nursing, Northeastern University, Boston, MA, USA
| | - Nikolaos Fourligas
- Developmental Biopsychiatry Research Program, McLean Hospital, 115 Mill Street, Belmont, MA, 02478, USA,Department of Biomedical Engineering, Tufts University, Medford, MA, USA
| | - Gordana Vitaliano
- Developmental Biopsychiatry Research Program, McLean Hospital, 115 Mill Street, Belmont, MA, 02478, USA,Department of Psychiatry, Harvard Medical School, Boston, MA, USA
| | - Carryl P Navalta
- Developmental Biopsychiatry Research Program, McLean Hospital, 115 Mill Street, Belmont, MA, 02478, USA,Mental Health Counseling & Behavioral Medicine Program, Boston University School of Medicine, Boston, MA, USA
| |
Collapse
|
10
|
Pinborg LH, Feng L, Haahr ME, Gillings N, Dyssegaard A, Madsen J, Svarer C, Yndgaard S, Kjaer TW, Parsey RV, Hansen HD, Ettrup A, Paulson OB, Knudsen GM. No change in [¹¹C]CUMI-101 binding to 5-HT(1A) receptors after intravenous citalopram in human. Synapse 2012; 66:880-4. [PMID: 22730164 DOI: 10.1002/syn.21579] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2012] [Revised: 06/05/2012] [Accepted: 06/13/2012] [Indexed: 11/12/2022]
Abstract
The main objective of this study was to determine the sensitivity of [¹¹C]CUMI-101 to citalopram challenge aiming at increasing extracellular 5-HT. CUMI-101 has agonistic properties in human embryonic kidney 293 cells transfected with human recombinant 5-HT(1A) receptors (Hendry et al. [2011] Nucl Med Biol 38:273-277; Kumar et al. [2006] J Med Chem 49:125-134) and has previously been demonstrated to be sensitive to bolus citalopram in monkeys (Milak et al. [2011] J Cereb Blood Flow Metab 31:243-249). We studied six healthy individuals. Two PET-scans were performed on the same day in each individual before and after constant infusion of citalopram (0.15 mg/kg). The imaging data were analyzed using two tissue compartment kinetic modeling with metabolite corrected arterial input and Simplified Reference Tissue Modeling using cerebellum as a reference region. There was no significant difference in regional distribution volume or non-displaceable binding potential values before and after citalopram infusion. The mean receptor occupancy was 0.03 (range -0.14 to 0.17). Our data imply that [¹¹C]CUMI-101 binding is not sensitive to citalopram infusion in humans.
Collapse
Affiliation(s)
- Lars H Pinborg
- Center for Integrated Molecular Brain Imaging, Rigshospitalet, Copenhagen University Hospital, Denmark.
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
11
|
Ningdong granule: a complementary and alternative therapy in the treatment of attention deficit/hyperactivity disorder. Psychopharmacology (Berl) 2011; 216:501-9. [PMID: 21416235 DOI: 10.1007/s00213-011-2238-z] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/29/2010] [Accepted: 02/18/2011] [Indexed: 10/18/2022]
Abstract
BACKGROUND Attention deficit/hyperactivity disorder (ADHD) is a common neurobehavioral and neuropsychiatric disorder in school-age children, and recent studies provide evidence implicating the metabolic abnormalities of dopamine (DA) for its pathophysiology. Methylphenidate, a kind of psychostimulant, is widely used in the treatment of ADHD, but some patients do not respond to it or cannot bear its side effects. As a traditional Chinese medicine preparation, Ningdong granule (NDG) has been used in the treatment of ADHD for several years in China. However, a systematical pharmacological study on its safety and mechanism still remains obscure. OBJECTIVE This paper aims to evaluate the efficiency, safety, and possible mechanism of NDG on ADHD children compared to methylphenidate. METHODS Seventy-two ADHD children were recruited to perform an 8-week, randomized, methylphenidate-controlled, doubled-blinded trial. The subjects were equally assigned to two groups receiving either NDG 5 mg/kg/day or methylphenidate 1 mg/kg/day for 8 weeks. The efficiency was assessed by the Teacher and Parent ADHD Rating Scales every 2 weeks for a total of 8 weeks. The side effects were recorded during the study. Blood, urine, and stool routine samples, liver and renal function test, and DA and homovanillic acid (HVA) concentration in sera were tested at the beginning and end of the trial. RESULTS NDG ameliorated ADHD symptoms after an 8-week medication with fewer side effects compared to methylphenidate (P < 0.05). The result also showed NDG to be safe and tolerable for ADHD children as monitored by the blood, urine, and stool analysis and liver and renal function for 8 weeks (P < 0.05). Moreover, the level of HVA in sera increased in NDG-treated group (P < 0.05), while the content of DA had no significant change during the study. An analysis of Pearson correlation coefficients also showed that the increased content of HVA in sera was associated with the improved scores of Teacher and Parent ADHD Rating Scales. CONCLUSIONS Compared to methylphenidate, NDG is effective and safe for ADHD children in the short term, increases the HVA concentration in sera to regulate DA metabolism, and promises to be an alternative medication, safely and effectively.
Collapse
|
12
|
Abstract
Molecular in vivo neuroimaging techniques can be used to measure regional changes in endogenous neurotransmitters, evoked by challenges that alter synaptic neurotransmitter concentration. This technique has most successfully been applied to the study of endogenous dopamine release using positron emission tomography, but has not yet been adequately extended to other neurotransmitter systems. This review focuses on how the technique has been applied to the study of the 5-hydroxytryptamine (5-HT) system. The principles behind visualising fluctuations in neurotransmitters are introduced, with reference to the dopaminergic system. Studies that aim to image acute, endogenous 5-HT release or depletion at 5-HT receptor targets are summarised, with particular attention to studies in humans. Radiotracers targeting the 5-HT(1A), 5-HT(2A), and 5-HT(4) receptors and the serotonin reuptake transporter have been explored for their sensitivity to 5-HT fluctuations, but with mixed outcomes; tracers for these targets cannot reliably image endogenous 5-HT in humans. Shortcomings in our basic knowledge of the mechanisms underlying changes in binding potential are addressed, and suggestions are made as to how the selection of targets, radiotracers, challenge paradigms, and experimental design might be optimised to improve our chances of successfully imaging endogenous neurotransmitters in the future.
Collapse
|
13
|
Study of the neural basis of striatal modulation of the jaw-opening reflex. J Neural Transm (Vienna) 2009; 117:171-81. [PMID: 20012111 DOI: 10.1007/s00702-009-0348-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2009] [Accepted: 11/23/2009] [Indexed: 12/21/2022]
Abstract
Previous experimental data from this laboratory demonstrated the participation of the striatum and dopaminergic pathways in central nociceptive processing. The objective of this study was to examine the possible pathways and neural structures associated with the analgesic action of the striatum. The experiments were carried out in rats anesthetized with urethane. The jaw-opening reflex (JOR) was evoked by electrical stimulation of the tooth pulp of lower incisors and recorded in the anterior belly of the digastric muscles. Intrastriatal microinjection of apomorphine, a nonspecific dopamine agonist, reduced or abolished the JOR amplitude. Electrolytic or kainic acid lesions, unilateral to the apomorphine-injected striatum, of the globus pallidus, substantia nigra pars reticulata, subthalamic nucleus and bilateral lesion the rostroventromedial medulla (RVM), blocked the inhibition of the JOR by striatal stimulation. These findings suggest that the main output nuclei of the striatum and the RVM may be critical elements in the neural pathways mediating the inhibition of the reflex response, evoked in jaw muscles by noxious stimulation of dental pulp.
Collapse
|
14
|
Abstract
The prefrontal cortex is necessary for directing thought and planning action. Working memory, the active, transient maintenance of information in mind for subsequent monitoring and manipulation, lies at the core of many simple, as well as high-level, cognitive functions. Working memory has been shown to be compromised in a number of neurological and psychiatric conditions and may contribute to the behavioral and cognitive deficits associated with these disorders. It has been theorized that working memory depends upon reverberating circuits within the prefrontal cortex and other cortical areas. However, recent work indicates that intracellular signals and protein dephosphorylation are critical for working memory. The present article will review recent research into the involvement of the modulatory neurotransmitters and their receptors in working memory. The intracellular signaling pathways activated by these receptors and evidence that indicates a role for G(q)-initiated PI-PLC and calcium-dependent protein phosphatase calcineurin activity in working memory will be discussed. Additionally, the negative influence of calcium- and cAMP-dependent protein kinase (i.e., calcium/calmodulin-dependent protein kinase II (CaMKII), calcium/diacylglycerol-activated protein kinase C (PKC), and cAMP-dependent protein kinase A (PKA)) activities on working memory will be reviewed. The implications of these experimental findings on the observed inverted-U relationship between D(1) receptor stimulation and working memory, as well as age-associated working memory dysfunction, will be presented. Finally, we will discuss considerations for the development of clinical treatments for working memory disorders.
Collapse
Affiliation(s)
- Pramod K Dash
- The Vivian L. Smith Center for Neurologic Research, and Department of Neurobiology and Anatomy, The University of Texas Medical School, Houston, Texas 77225, USA.
| | | | | | | |
Collapse
|