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Liang HB, He WY, Liu YP, Wang HB. Pain Comorbidities with Attention Deficit: A Narrative Review of Clinical and Preclinical Research. J Pain Res 2024; 17:1055-1065. [PMID: 38505503 PMCID: PMC10948333 DOI: 10.2147/jpr.s443915] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2023] [Accepted: 02/23/2024] [Indexed: 03/21/2024] Open
Abstract
A negative correlation exists between attention and pain. The cognitive impairments linked to pain can significantly impede a patient's healing process and everyday tasks, particularly for individuals experiencing persistent pain. Furthermore, it has been demonstrated that diversion can effectively decrease pain levels in individuals. The focus of this review is to analyze clinical trials and fundamental investigations regarding alterations in focus and persistent discomfort. Moreover, we investigated the common neuroanatomy associated with attention and pain. Furthermore, we examined the impact of various neuromodulators on the transmission of pain and processes related to attention, while also considering the potential neural mechanisms that contribute to the co-occurrence of pain and attention deficits. Further investigation in this field will enhance our comprehension of patient symptoms and the underlying pathophysiology, ultimately resulting in more objective approaches to treatment.
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Affiliation(s)
- Hong-Bin Liang
- Graduate School of Guangdong Medical University, Zhanjiang, Guangdong Province, People’s Republic of China
- Department of Anesthesiology, The First People’s Hospital of Foshan, Foshan, Guangdong Province, People’s Republic of China
| | - Wan-You He
- Department of Anesthesiology, The First People’s Hospital of Foshan, Foshan, Guangdong Province, People’s Republic of China
| | - Yan-Ping Liu
- College of Nursing, Shandong First Medical University (Shandong Academy of Medical Science), Jinan, Shandong Province, People’s Republic of China
| | - Han-Bing Wang
- Graduate School of Guangdong Medical University, Zhanjiang, Guangdong Province, People’s Republic of China
- Department of Anesthesiology, The First People’s Hospital of Foshan, Foshan, Guangdong Province, People’s Republic of China
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2
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Klem L, Nielsen MM, Gestsdóttir SB, Frandsen SL, Prichardt S, Andreasen JT. Assessing attention and impulsivity in the variable stimulus duration and variable intertrial interval rodent continuous performance test schedules using noradrenaline receptor antagonists in female C57BL/6JRj mice. Psychopharmacology (Berl) 2023; 240:1629-1650. [PMID: 37329343 PMCID: PMC10349758 DOI: 10.1007/s00213-023-06385-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2022] [Accepted: 05/10/2023] [Indexed: 06/19/2023]
Abstract
RATIONALE Noradrenergic dysfunction is associated with disorders of impulsivity and inattention. The rodent continuous performance test (rCPT) quantifies changes in attention and impulsivity. OBJECTIVE To use NA receptor antagonists to examine the roles of NA on attention and impulsivity behaviours measured in the rCPT variable stimulus duration (vSD) and the variable intertrial interval (vITI) schedules. METHODS Two cohorts of 36 female C57BL/6JRj mice were examined separately in the rCPT vSD and vITI schedules. Both cohorts received antagonists of the following adrenoceptors: α1 (doxazosin, DOX: 1.0, 3.0, 10.0 mg/kg), α2 (yohimbine, YOH: 0.1, 0.3, 1.0 mg/kg), and β1/2 (propranolol, PRO: 1.0, 3.0, 10.0 mg/kg) in consecutive balanced Latin square designs with flanking reference measurements. The antagonists were subsequently examined for effects on locomotor activity. RESULTS DOX showed similar effects in both schedules, improving discriminability and accuracy, and reducing responding and impulsivity, and DOX also reduced locomotor activity. YOH showed prominent effects in the vSD schedule to increase responding and impulsivity, while impairing discriminability and accuracy. YOH did not affect locomotor activity. PRO increased responding and impulsivity, decreased accuracy, but did not affect discriminability or locomotor activity. CONCLUSION Antagonism of α2 or β1/2 adrenoceptors caused similar increases in responding and impulsivity and worsened attentional performance, while α1 adrenoceptor antagonism showed the opposite effects. Our results suggest that endogenous NA exerts bidirectional control of most behaviours in the rCPT. The parallel vSD and vITI studies showed a substantial overlap in effects, but also some differences that indicate differing sensitivity towards noradrenergic manipulations.
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Affiliation(s)
- L Klem
- Dept. of Drug Design and Pharmacology, University of Copenhagen, Universitetsparken 2, 2100, Copenhagen, Denmark
| | - M M Nielsen
- Dept. of Drug Design and Pharmacology, University of Copenhagen, Universitetsparken 2, 2100, Copenhagen, Denmark
| | - S B Gestsdóttir
- Dept. of Drug Design and Pharmacology, University of Copenhagen, Universitetsparken 2, 2100, Copenhagen, Denmark
| | - S L Frandsen
- Dept. of Drug Design and Pharmacology, University of Copenhagen, Universitetsparken 2, 2100, Copenhagen, Denmark
| | - S Prichardt
- Dept. of Drug Design and Pharmacology, University of Copenhagen, Universitetsparken 2, 2100, Copenhagen, Denmark
| | - J T Andreasen
- Dept. of Drug Design and Pharmacology, University of Copenhagen, Universitetsparken 2, 2100, Copenhagen, Denmark.
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3
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Sifeddine W, Ba-M'hamed S, Landry M, Bennis M. Effect of atomoxetine on ADHD-pain hypersensitization comorbidity in 6-OHDA lesioned mice. Pharmacol Rep 2023; 75:342-357. [PMID: 36787018 DOI: 10.1007/s43440-023-00459-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2022] [Revised: 01/26/2023] [Accepted: 01/31/2023] [Indexed: 02/15/2023]
Abstract
BACKGROUND Methylphenidate and atomoxetine are used for the treatment of attention-deficit/hyperactivity disorder (ADHD). Our previous studies established the validity of the 6-hydroxydopamine (6-OHDA) mouse model of ADHD and demonstrated hypersensitivity to pain, in line with clinical reports in ADHD patients. Acute methylphenidate treatment reduces hyperactivity and increases attention, but does not affect pain behaviors in this mouse model. Whereas atomoxetine has been shown to be effective against some symptoms of ADHD, nothing is known about its possible action on comorbid pain hypersensitivity. The objectives of the present research are (1) to investigate the effects of acute and chronic treatment with atomoxetine on ADHD-like symptoms and nociceptive thresholds, and (2) to explore the catecholaminergic systems underlying these effects. METHODS Sham and 6-OHDA cohorts of male mice were tested for hyperactivity (open field), attention and impulsivity (5-choice serial reaction time task test), and thermal (hot plate test) and mechanical (von Frey test) thresholds after acute or repeated treatment with vehicle or atomoxetine (1, 3 or 10 mg/kg). RESULTS Acute administration of atomoxetine (10 mg/kg) reduced the hyperactivity and impulsivity displayed by 6-OHDA mice, without affecting attention or nociception. However, atomoxetine administered at 3 mg/kg/day for 7 days alleviated the ADHD-like core symptoms and attenuated the hyperalgesic responses. Furthermore, hyperlocomotion and anti-hyperalgesic activity were antagonized with phentolamine, propranolol, and sulpiride pre-treatments. CONCLUSION These findings demonstrated that when administered chronically, atomoxetine has a significant effect on ADHD-associated pain hypersensitization, likely mediated by both α- and β-adrenergic and D2/D3 dopaminergic receptors, and suggest new indications for atomoxetine that will need to be confirmed by well-designed clinical trials.
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Affiliation(s)
- Wahiba Sifeddine
- Laboratory of Pharmacology, Neurobiology, Anthropobiology, and Environment, Faculty of Sciences, Cadi Ayyad University, Avenue Prince My Abdellah, B.P. 2390, 40000, Marrakesh, Morocco
| | - Saadia Ba-M'hamed
- Laboratory of Pharmacology, Neurobiology, Anthropobiology, and Environment, Faculty of Sciences, Cadi Ayyad University, Avenue Prince My Abdellah, B.P. 2390, 40000, Marrakesh, Morocco
| | - Marc Landry
- University of Bordeaux, CNRS, Institute of Neurodegenerative Diseases, UMR 5293, Bordeaux, France.,University of Bordeaux, CNRS, INSERM, Bordeaux Imaging Center, UMS 3420, US 4, Bordeaux, France
| | - Mohamed Bennis
- Laboratory of Pharmacology, Neurobiology, Anthropobiology, and Environment, Faculty of Sciences, Cadi Ayyad University, Avenue Prince My Abdellah, B.P. 2390, 40000, Marrakesh, Morocco.
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Graczyk MM, Sahakian BJ, Robbins TW, Ersche KD. Genotype-by-diagnosis interaction influences self-control in human cocaine addiction. Transl Psychiatry 2023; 13:51. [PMID: 36774338 PMCID: PMC9922269 DOI: 10.1038/s41398-023-02347-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Revised: 01/22/2023] [Accepted: 01/30/2023] [Indexed: 02/13/2023] Open
Abstract
Not everyone who uses drugs loses control over their intake, which is a hallmark of addiction. Although familial risk studies suggest significant addiction heritability, the genetic basis of vulnerability to drug addiction remains largely unknown. In the present study, we investigate the relationship between self-control, cocaine use, and the rs36024 single nucleotide polymorphism of the noradrenaline transporter gene (SLC6A2). We hypothesize that C-allele-carrying adults show impaired self-control, as measured by the stop-signal task and demonstrated previously in adolescents, and further exacerbated by chronic cocaine use. Patients with cocaine use disorder (CUD, n = 79) and healthy unrelated participants with no history of drug abuse (n = 54) completed the stop-signal task. All participants were genotyped for rs36024 allelic variants (CC/TT homozygotes, CT heterozygotes). We measured mean stop-signal reaction time, reflecting the ability to inhibit ongoing motor responses, reaction times to go stimuli, and the proportion of successful stops. CUD patients showed prolonged stop-signal reaction time, however, there was no main effect of rs36024 genotype. Importantly, there was a significant genotype-by-diagnosis interaction such that CUD patients with CC genotype had longer stop-signal reaction time and fewer successful stops compared with CC healthy controls and TT CUD patients. CT CUD patients showed an intermediate performance. Self-control deficits were associated with cocaine use disorder diagnosis, which interacts with the noradrenaline transporter rs36024 polymorphism. Our findings suggest that rs36024 may represent a potential genetic vulnerability marker, which facilitates the transition from first cocaine use to addiction by weakening the inhibitory control over behavior.
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Affiliation(s)
- Michal M Graczyk
- Department of Psychiatry, University of Cambridge, Cambridge, UK
| | | | - Trevor W Robbins
- Department of Psychology, University of Cambridge, Cambridge, UK
| | - Karen D Ersche
- Department of Psychiatry, University of Cambridge, Cambridge, UK.
- Department of Systems Neuroscience, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
- Department of Addictive Behaviour and Addiction Medicine, Central Institute of Mental Health, University of Heidelberg, Mannheim, Germany.
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Redding ZV, Sabol KE. Reduced attentional lapses in male rats following a combination treatment of low-dose D-serine and atomoxetine. J Psychopharmacol 2023; 37:204-215. [PMID: 36648101 DOI: 10.1177/02698811221149652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
BACKGROUND Goal-directed attention involves the selective processing of behaviorally relevant sensory information. This selective processing is thought to be supported by glutamatergic and noradrenergic systems. Pharmacotherapies that simultaneously target these systems could therefore be effective treatments for impaired attention. AIMS We first tested an N-methyl-D-aspartate (NMDA) receptor co-agonist (D-serine) for effects on attention (processing speed and attentional lapses). NMDA receptor activation is thought to support noradrenergic effects on sensory processing; therefore, we tested a combination treatment comprising D-serine and a norepinephrine reuptake inhibitor (atomoxetine). METHODS D-serine was first tested in rats performing a two-choice visuospatial discrimination task. Combination treatments comprising relatively low doses of D-serine and atomoxetine were then tested in a separate group. RESULTS In experiment 1, D-serine reduced the skew of initiation time (IT) distributions (IT devmode) at the highest dose tested (300 mg/kg). In experiment 2, low-dose D-serine (125 mg/kg) had no effect, while low-dose atomoxetine (0.3 mg/kg) reduced IT devmode and slowed movement speed. Importantly, the combination of these relatively low doses of D-serine and atomoxetine reduced IT devmode more than either drug alone without further slowing movement speed. CONCLUSIONS IT devmode is thought to reflect attentional lapses; therefore, D-serine's effects on IT devmode suggest that NMDA receptors are involved in the preparatory deployment of attention. Greater effects following a combination of D-serine and atomoxetine suggest that preparatory attention can be facilitated by targeting glutamatergic and noradrenergic systems simultaneously. These results could inform the development of improved treatments for individuals with ADHD who experience abnormally high attentional lapses.
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Affiliation(s)
- Zach V Redding
- Department of Psychology, The University of Mississippi, University Park, MS, USA.,Department of Neuroscience, University of Rochester Medical Center, Rochester, NY, USA
| | - Karen E Sabol
- Department of Psychology, The University of Mississippi, University Park, MS, USA
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6
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Hervig MES, Toschi C, Petersen A, Vangkilde S, Gether U, Robbins TW. Theory of visual attention (TVA) applied to rats performing the 5-choice serial reaction time task: differential effects of dopaminergic and noradrenergic manipulations. Psychopharmacology (Berl) 2023; 240:41-58. [PMID: 36434307 PMCID: PMC9816296 DOI: 10.1007/s00213-022-06269-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Accepted: 10/21/2022] [Indexed: 11/27/2022]
Abstract
RATIONALE Attention is compromised in many psychiatric disorders, including attention-deficit/hyperactivity disorder (ADHD). While dopamine and noradrenaline systems have been implicated in ADHD, their exact role in attentional processing is yet unknown. OBJECTIVES We applied the theory of visual attention (TVA) model, adapted from human research, to the rat 5-choice serial reaction time task (5CSRTT) to investigate catecholaminergic modulation of visual attentional processing in healthy subjects of high- and low-attention phenotypes. METHODS Rats trained on the standard 5CSRTT and tested with variable stimulus durations were treated systemically with noradrenergic and/or dopaminergic agents (atomoxetine, methylphenidate, amphetamine, phenylephrine and atipamezole). TVA modelling was applied to estimate visual processing speed for correct and incorrect visual perceptual categorisations, independent of motor reaction times, as measures of attentional capacity. RESULTS Atomoxetine and phenylephrine decreased response frequencies, including premature responses, increased omissions and slowed responding. In contrast, methylphenidate, amphetamine and atipamezole sped up responding and increased premature responses. Visual processing speed was also affected differentially. Atomoxetine and phenylephrine slowed, whereas methylphenidate and atipamezole sped up, visual processing, both for correct and incorrect categorisations. Amphetamine selectively improved visual processing for correct, though not incorrect, responses in high-attention rats only, possibly reflecting improved attention. CONCLUSIONS These data indicate that the application of TVA to the 5CSRTT provides an enhanced sensitivity to capturing attentional effects. Unexpectedly, we found overall slowing effects, including impaired visual processing, following drugs either increasing extracellular noradrenaline (atomoxetine) or activating the α1-adrenoceptor (phenylephrine), while also ameliorating premature responses (impulsivity). In contrast, amphetamine had potential pro-attentional effects by enhancing visual processing, probably due to central dopamine upregulation.
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Affiliation(s)
- Mona El-Sayed Hervig
- Department of Psychology and Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge, UK. .,Department of Neuroscience, University of Copenhagen, Copenhagen, Denmark.
| | - Chiara Toschi
- Department of Psychology and Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge, UK
| | - Anders Petersen
- Department of Psychology, University of Copenhagen, Copenhagen, Denmark
| | - Signe Vangkilde
- Department of Psychology, University of Copenhagen, Copenhagen, Denmark
| | - Ulrik Gether
- Department of Neuroscience, University of Copenhagen, Copenhagen, Denmark
| | - Trevor W. Robbins
- Department of Psychology and Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge, UK
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7
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Dutta CN, Christov-Moore L, Ombao H, Douglas PK. Neuroprotection in late life attention-deficit/hyperactivity disorder: A review of pharmacotherapy and phenotype across the lifespan. Front Hum Neurosci 2022; 16:938501. [PMID: 36226261 PMCID: PMC9548548 DOI: 10.3389/fnhum.2022.938501] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2022] [Accepted: 08/16/2022] [Indexed: 11/13/2022] Open
Abstract
For decades, psychostimulants have been the gold standard pharmaceutical treatment for attention-deficit/hyperactivity disorder (ADHD). In the United States, an astounding 9% of all boys and 4% of girls will be prescribed stimulant drugs at some point during their childhood. Recent meta-analyses have revealed that individuals with ADHD have reduced brain volume loss later in life (>60 y.o.) compared to the normal aging brain, which suggests that either ADHD or its treatment may be neuroprotective. Crucially, these neuroprotective effects were significant in brain regions (e.g., hippocampus, amygdala) where severe volume loss is linked to cognitive impairment and Alzheimer's disease. Historically, the ADHD diagnosis and its pharmacotherapy came about nearly simultaneously, making it difficult to evaluate their effects in isolation. Certain evidence suggests that psychostimulants may normalize structural brain changes typically observed in the ADHD brain. If ADHD itself is neuroprotective, perhaps exercising the brain, then psychostimulants may not be recommended across the lifespan. Alternatively, if stimulant drugs are neuroprotective, then this class of medications may warrant further investigation for their therapeutic effects. Here, we take a bottom-up holistic approach to review the psychopharmacology of ADHD in the context of recent models of attention. We suggest that future studies are greatly needed to better appreciate the interactions amongst an ADHD diagnosis, stimulant treatment across the lifespan, and structure-function alterations in the aging brain.
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Affiliation(s)
- Cintya Nirvana Dutta
- Biostatistics Group, Computer, Electrical and Mathematical Sciences and Engineering Division, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
- School of Modeling, Simulation, and Training, and Computer Science, University of Central Florida, Orlando, FL, United States
| | - Leonardo Christov-Moore
- Brain and Creativity Institute, University of Southern California, Los Angeles, CA, United States
| | - Hernando Ombao
- Biostatistics Group, Computer, Electrical and Mathematical Sciences and Engineering Division, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia
| | - Pamela K. Douglas
- School of Modeling, Simulation, and Training, and Computer Science, University of Central Florida, Orlando, FL, United States
- Department of Psychiatry and Biobehavioral Medicine, University of California, Los Angeles, Los Angeles, CA, United States
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8
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Functional Coupling of the Locus Coeruleus Is Linked to Successful Cognitive Control. Brain Sci 2022; 12:brainsci12030305. [PMID: 35326262 PMCID: PMC8946131 DOI: 10.3390/brainsci12030305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2022] [Revised: 02/13/2022] [Accepted: 02/17/2022] [Indexed: 11/20/2022] Open
Abstract
The locus coeruleus (LC) is a brainstem structure that sends widespread efferent projections throughout the mammalian brain. The LC constitutes the major source of noradrenaline (NE), a modulatory neurotransmitter that is crucial for fundamental brain functions such as arousal, attention, and cognitive control. This role of the LC-NE is traditionally not believed to reflect functional influences on the frontoparietal network or the striatum, but recent advances in chemogenetic manipulations of the rodent brain have challenged this notion. However, demonstrations of LC-NE functional connectivity with these areas in the human brain are surprisingly sparse. Here, we close this gap. Using an established emotional stroop task, we directly compared trials requiring response conflict control with trials that did not require this, but were matched for visual stimulus properties, response modality, and controlled for pupil dilation differences across both trial types. We found that LC-NE functional coupling with the parietal cortex and regions of the striatum is substantially enhanced during trials requiring response conflict control. Crucially, the strength of this functional coupling was directly related to individual reaction time differences incurred by conflict resolution. Our data concur with recent rodent findings and highlight the importance of converging evidence between human and nonhuman neurophysiology to further understand the neural systems supporting adaptive and maladaptive behavior in health and disease.
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Higgins GA, Silenieks LB. The Effects of Drug Treatments for ADHD in Measures of Cognitive Performance. Curr Top Behav Neurosci 2022; 57:321-362. [PMID: 35606638 DOI: 10.1007/7854_2022_341] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Based on core symptoms of inattention and deficient impulse control, and the identification of effective pharmacotherapies such as amphetamine (AMP; Adderall®), methylphenidate (MPH; Ritalin®), and atomoxetine (ATX; Strattera®), ADHD is a clinical condition which provides opportunity for translational research. Neuropsychological tests such as the 5-Choice and Continuous Performance Tasks, which measure aspects of attention and impulse control in animals and humans, provide scope for both forward (animal to human) and reverse (human to animal) translation. Rodent studies support pro-attentive effects of AMP and MPH and effectiveness in controlling some forms of impulsive behavior. In contrast, any pro-attentive effects of ATX appear to be less consistent, the most reliable effects of ATX are recorded in tests of impulsivity. These differences may account for AMP and MPH being recognized as first-line treatments for ADHD with a higher efficacy relative to ATX. DSM-5 classifies three "presentations" of ADHD: predominantly inattentive type (ADHD-I), predominantly hyperactive/impulsive type (ADHD-HI), or combined (ADHD-C). Presently, it is unclear whether AMP, MPH, or ATX has differential levels of efficacy across these presentation types. Nonetheless, these studies encourage confidence for the forward translation of NCEs in efforts to identify newer pharmacotherapies for ADHD.
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Affiliation(s)
- Guy A Higgins
- Intervivo Solutions, Toronto, ON, Canada.
- Department of Pharmacology and Toxicology, University of Toronto, Toronto, ON, Canada.
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10
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Toschi C, Hervig MES, Moazen P, Parker MG, Dalley JW, Gether U, Robbins TW. Adaptive aspects of impulsivity and interactions with effects of catecholaminergic agents in the 5-choice serial reaction time task: implications for ADHD. Psychopharmacology (Berl) 2021; 238:2601-2615. [PMID: 34104987 PMCID: PMC8373759 DOI: 10.1007/s00213-021-05883-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Accepted: 05/21/2021] [Indexed: 01/14/2023]
Abstract
BACKGROUND Work in humans has shown that impulsivity can be advantageous in certain settings. However, evidence for so-called functional impulsivity is lacking in experimental animals. AIMS This study investigated the contexts in which high impulsive (HI) rats show an advantage in performance compared with mid- (MI) and low impulsive (LI) rats. We also assessed the effects of dopaminergic and noradrenergic agents to investigate underlying neurotransmitter mechanisms. METHODS We tested rats on a variable inter-trial interval (ITI) version of the 5-choice serial reaction time task (5CSRTT). Rats received systemic injections of methylphenidate (MPH, 1 mg/kg and 3 mg/kg), atomoxetine (ATO, 0.3 mg/kg and 1 mg/kg), amphetamine (AMPH, 0.2 mg/kg), the alpha-2a adrenoceptor antagonist atipamezole (ATI, 0.3 mg/kg) and the alpha-1 adrenoceptor agonist phenylephrine (PHEN, 1 mg/kg) prior to behavioural testing. RESULTS Unlike LI rats, HI rats exhibited superior performance, earning more reinforcers, on short ITI trials, when the task required rapid responding. MPH, AMPH and ATI improved performance on short ITI trials and increased impulsivity in long ITI trials, recapitulating the behavioural profile of HI. In contrast, ATO and PHEN impaired performance on short ITI trials and decreased impulsivity, thus mimicking the behavioural profile of LI rats. The effects of ATO were greater on MI rats and LI rats. CONCLUSIONS These findings indicate that impulsivity can be advantageous when rapid focusing and actions are required, an effect that may depend on increased dopamine neurotransmission. Conversely, activation of the noradrenergic system, with ATO and PHEN, led to a general inhibition of responding.
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Affiliation(s)
- Chiara Toschi
- Department of Psychology and Behavioural and Clinical Neuroscience Institute, University of Cambridge, Downing St., CB2 3EB, Cambridge, UK.
| | - Mona El-Sayed Hervig
- Department of Psychology and Behavioural and Clinical Neuroscience Institute, University of Cambridge, Downing St., CB2 3EB, Cambridge, UK
- Department of Neuroscience, University of Copenhagen, DK-2200, Copenhagen, Denmark
| | - Parisa Moazen
- Department of Psychology and Behavioural and Clinical Neuroscience Institute, University of Cambridge, Downing St., CB2 3EB, Cambridge, UK
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Maximilian G Parker
- Department of Psychology and Behavioural and Clinical Neuroscience Institute, University of Cambridge, Downing St., CB2 3EB, Cambridge, UK
| | - Jeffrey W Dalley
- Department of Psychology and Behavioural and Clinical Neuroscience Institute, University of Cambridge, Downing St., CB2 3EB, Cambridge, UK
- Department of Psychiatry, University of Cambridge, Cambridge Biomedical Campus, Cambridge, UK
| | - Ulrik Gether
- Department of Neuroscience, University of Copenhagen, DK-2200, Copenhagen, Denmark
| | - Trevor W Robbins
- Department of Psychology and Behavioural and Clinical Neuroscience Institute, University of Cambridge, Downing St., CB2 3EB, Cambridge, UK
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11
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Mei X, Wang L, Yang B, Li X. Sex differences in noradrenergic modulation of attention and impulsivity in rats. Psychopharmacology (Berl) 2021; 238:2167-2177. [PMID: 33834255 DOI: 10.1007/s00213-021-05841-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/14/2020] [Accepted: 03/29/2021] [Indexed: 01/01/2023]
Abstract
RATIONALE Noradrenaline (NE) is closely related to attentive performance and impulsive control. However, the potential sex differences regarding attention and impulsivity under the noradrenergic modulation have been largely neglected. Therefore, our study aimed to investigate whether male and female rats exhibit differential responses to NE-related drugs during the five-choice serial reaction time task (5CSRT). METHODS Male and female rats were trained in 5CSRT and administered with different NE drugs after obtaining stable baseline performance: atipamezole, a highly selective α2 receptor antagonist; prazosin, an α1 receptor antagonist; and atomoxetine, a selective NE reuptake inhibitor. Later, prazosin was selected to co-administration with atomoxetine. RESULTS Male and female rats exhibited equal learning speed, and no significant baseline differences were found as measured by the 5CSRT. Atomoxetine decreased premature responses in both sexes, but the extent of this reduction was different, with the reduction greater in males. Besides, atomoxetine (1.8 mg/kg) increased the error of omissions in females. The high dose of prazosin (0.5 mg/kg) decreased the accuracy only in male rats, but this was ameliorated by the co-administration with atomoxetine. CONCLUSIONS Atomoxetine showed significant improvement in impulsivity, but atomoxetine had less beneficial effects on impulsive control in females than in males, and it even impaired attentional performance in female rats. The α1 receptors were mainly responsible for NE drug-related sex differences in attention rather than impulsivity. The results obtained in this study indicate that the sex differences exist in both attention and impulsivity by the modulation of noradrenaline and raise the concern to improve sex-specific treatments.
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Affiliation(s)
- Xiaolin Mei
- College of Psychology, Capital Normal University, Beijing, 100048, China
- Department of Psychology, Sun Yat-Sen University, Guangzhou, 510275, China
| | - Lutong Wang
- College of Psychology, Capital Normal University, Beijing, 100048, China
| | - Bo Yang
- Department of Psychology, Sun Yat-Sen University, Guangzhou, 510275, China
| | - Xinwang Li
- College of Psychology, Capital Normal University, Beijing, 100048, China.
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12
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Differential attentional control mechanisms by two distinct noradrenergic coeruleo-frontal cortical pathways. Proc Natl Acad Sci U S A 2020; 117:29080-29089. [PMID: 33139568 DOI: 10.1073/pnas.2015635117] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
The attentional control of behavior is a higher-order cognitive function that operates through attention and response inhibition. The locus coeruleus (LC), the main source of norepinephrine in the brain, is considered to be involved in attentional control by modulating the neuronal activity of the prefrontal cortex (PFC). However, evidence for the causal role of LC activity in attentional control remains elusive. Here, by using behavioral and optogenetic techniques, we investigate the effect of LC neuron activation or inhibition in operant tests measuring attention and response inhibition (i.e., a measure of impulsive behavior). We show that LC neuron stimulation increases goal-directed attention and decreases impulsivity, while its suppression exacerbates distractibility and increases impulsive responding. Remarkably, we found that attention and response inhibition are under the control of two divergent projections emanating from the LC: one to the dorso-medial PFC and the other to the ventro-lateral orbitofrontal cortex, respectively. These findings are especially relevant for those pathological conditions characterized by attention deficits and elevated impulsivity.
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Higgins GA, Silenieks LB, MacMillan C, Thevarkunnel S, Parachikova AI, Mombereau C, Lindgren H, Bastlund JF. Characterization of Amphetamine, Methylphenidate, Nicotine, and Atomoxetine on Measures of Attention, Impulsive Action, and Motivation in the Rat: Implications for Translational Research. Front Pharmacol 2020; 11:427. [PMID: 32390829 PMCID: PMC7193984 DOI: 10.3389/fphar.2020.00427] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Accepted: 03/19/2020] [Indexed: 12/18/2022] Open
Abstract
Amphetamine (AMP), methylphenidate (MPH), and atomoxetine (ATX) are approved treatments for ADHD, and together with nicotine (NIC), represent pharmacological agents widely studied on cognitive domains including attention and impulsive action in humans. These agents thus represent opportunities for clinical observation to be reinvestigated in the preclinical setting, i.e., reverse translation. The present study investigated each drug in male, Long Evans rats trained to perform either (1) the five-choice serial reaction time task (5-CSRTT), (2) Go/NoGo task, or (3) a progressive ratio (PR) task, for the purpose of studying each drug on attention, impulsive action and motivation. Specific challenges were adopted in the 5-CSRTT designed to tax attention and impulsivity, i.e., high frequency of stimulus presentation (sITI), variable reduction in stimulus duration (sSD), and extended delay to stimulus presentation (10-s ITI). Initially, performance of a large (> 80) cohort of rats in each task variant was conducted to examine performance stability over repeated challenge sessions, and to identify subgroups of "high" and "low" attentive rats (sITI and sSD schedules), and "high" and "low" impulsives (10-s ITI). Using an adaptive sequential study design, the effects of AMP, MPH, ATX, and NIC were examined and contrasting profiles noted across the tests. Both AMP (0.03-0.3 mg/kg) and MPH (1-6 mg/kg) improved attentional performance in the sITI but not sSD or 10-s ITI condition, NIC (0.05-0.2 mg/kg) improved accuracy across all conditions. ATX (0.1-1 mg/kg) detrimentally affected performance in the sITI and sSD condition, notably in "high" performers. In tests of impulsive action, ATX reduced premature responses notably in the 10-s ITI condition, and also reduced false alarms in Go/NoGo. Both AMP and NIC increased premature responses in all task variants, although AMP reduced false alarms highlighting differences between these two measures of impulsive action. The effect of MPH was mixed and appeared baseline dependent. ATX reduced break point for food reinforcement suggesting a detrimental effect on motivation for primary reward. Taken together these studies highlight differences between AMP, MPH, and ATX which may translate to their clinical profiles. NIC had the most reliable effect on attentional accuracy, whereas ATX was reliably effective against all tests of impulsive action.
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Affiliation(s)
- Guy A Higgins
- Intervivo Solutions, Toronto, ON, Canada.,Department of Pharmacology & Toxicology, University of Toronto, Toronto, ON, Canada
| | | | | | | | | | | | - Hanna Lindgren
- Discovery Research, H. Lundbeck A/S, Copenhagen, Denmark
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14
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Abstract
Neuropharmacological interventions in preclinical translational models of impulsivity have tremendously contributed to a better understanding of the neurochemistry and neural basis of impulsive behaviour. In this regard, much progress has been made over the last years, also due to the introduction of novel techniques in behavioural neuroscience such as optogenetics and chemogenetics. In this chapter, we will provide an update of how the behavioural pharmacology field has progressed and built upon existing data since an earlier review we wrote in 2008. To this aim, we will first give a brief background on preclinical translational models of impulsivity. Next, recent interesting evidence of monoaminergic modulation of impulsivity will be highlighted with a focus on the neurotransmitters dopamine and noradrenaline. Finally, we will close the chapter by discussing some novel directions and drug leads in the neuropharmacological modulation of impulsivity.
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Affiliation(s)
- Tommy Pattij
- Department of Anatomy and Neurosciences, Amsterdam Neuroscience, Amsterdam University Medical Centers, VU University Medical Center, Amsterdam, The Netherlands.
| | - Louk J M J Vanderschuren
- Division of Behavioural Neuroscience, Department of Animals in Science and Society, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
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Barkus C, Ferland JMN, Adams WK, Churchill GC, Cowen PJ, Bannerman DM, Rogers RD, Winstanley CA, Sharp T. The putative lithium-mimetic ebselen reduces impulsivity in rodent models. J Psychopharmacol 2018; 32:1018-1026. [PMID: 29986609 DOI: 10.1177/0269881118784876] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
BACKGROUND Deficits in impulse control feature in many psychiatric conditions including bipolar disorder, suicidality and addictions. Lithium lowers impulsivity in clinical populations and decreases pathological gambling in experimental medicine studies, but suffers from adverse effects, poor compliance and a low therapeutic index. AIMS Recently we identified that the neuroprotective agent ebselen, which is reportedly safe in humans, inhibited inositol monophosphatase (IMPase), a candidate lithium mechanism. Ebselen also reduced 5-HT receptor (5-HT2A) function which predicts impulsivity lowering properties. Here we investigated the effect of ebselen in rat models of impulsive behaviour. METHODS Ebselen was tested in two models of impulsivity with human analogues: the five-choice serial reaction time task (5-CSRTT) and rodent gambling task (rGT). The main outcome measures were premature responses (5-CSRTT and rGT) and choice behaviour (rGT), which model motor impulsivity and choice impulsivity, respectively. RESULTS At doses that decreased 5-HT2A receptor function (DOI-induced wet dog shakes), ebselen decreased premature responding in the 5-CSRTT both in the absence and presence of cocaine. The 5-HT2A receptor antagonist MDL 100,907 also reduced premature responding in the 5-CSRTT although not in the presence of cocaine. In the rGT ebselen showed a tendency to reduce premature responding but had no effect on choice behaviour. CONCLUSIONS These findings suggest that ebselen preferentially reduces motor impulsivity over choice impulsivity, and that inhibition of 5-HT2A receptor function is a contributing mechanism. Collectively, these data support the repurposing of ebselen as an anti-impulsive treatment and fast-tracking to clinical trials in patient groups characterised by poor impulse control.
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Affiliation(s)
- Chris Barkus
- 1 Department of Pharmacology, University of Oxford, UK
- 2 Department of Psychology, University of British Columbia, Vancouver, Canada
| | | | - Wendy K Adams
- 2 Department of Psychology, University of British Columbia, Vancouver, Canada
| | | | | | | | | | | | - Trevor Sharp
- 1 Department of Pharmacology, University of Oxford, UK
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16
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Assessing disease-modifying effects of norepinephrine in Down syndrome and Alzheimer's disease. Brain Res 2017; 1702:3-11. [PMID: 29102776 DOI: 10.1016/j.brainres.2017.09.035] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Accepted: 09/18/2017] [Indexed: 11/23/2022]
Abstract
Building upon the knowledge that a number of important brain circuits undergo significant degeneration in Alzheimer's disease, numerous recent studies suggest that the norepinephrine-ergic system in the brainstem undergoes significant alterations early in the course of both Alzheimer's disease and Down syndrome. Massive projections from locus coeruleus neurons to almost the entire brain, extensive innervation of brain capillaries, and widespread distribution of noradrenergic receptors enable the norepinephrine-ergic system to play a crucial role in neural processes, including cognitive function. These anatomical and functional characteristics support the role of the norepinephrine-ergic system as an important target for developing new therapies for cognitive dysfunction. Careful neuropathological examinations using postmortem samples from individuals with Alzheimer's disease have implicated the role of the norepinephrine-ergic system in the etiopathogenesis of Alzheimer's disease. Furthermore, numerous studies have supported the existence of a strong interaction between norepinephrine-ergic and neuroimmune systems. We explore the interaction between the two systems that could play a role in the disease-modifying effects of norepinephrine in Alzheimer's disease and Down syndrome.
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Higgins GA, Silenieks LB. Rodent Test of Attention and Impulsivity: The 5-Choice Serial Reaction Time Task. ACTA ACUST UNITED AC 2017; 78:5.49.1-5.49.34. [PMID: 28892143 DOI: 10.1002/cpph.27] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
The 5-choice serial reaction time task (5-CSRTT) is employed extensively to measure attention in rodents. The assay involves animals trained to respond to a brief, unpredictable visual stimulus presented in one of five locations. The effects of experimental manipulations on response speed and choice accuracy are measured, and each related to attentional performance. The 5-CSRTT is also used to measure motor impulsivity. Adapted from a human task, the 5-CSRTT can be employed with rodents or primates, highlighting its translational value. Another strength of this procedure is its adaptability to task modification. An example is the 5-choice continuous performance task, which has both target and non-target trial types. Overall, the 5-CSRTT has proven to be valuable for drug discovery efforts aimed at identifying new agents for the treatment of central nervous system disorders and for further understanding the neurobiological processes of attention and impulsivity. Its flexibility offers considerable scope to the experimenter, and in this respect the task continues to evolve. © 2017 by John Wiley & Sons, Inc.
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Affiliation(s)
- Guy A Higgins
- InterVivoSolutions Inc, Toronto, Ontario, Canada.,Department of Pharmacology and Toxicology, University of Toronto, Toronto, Ontario, Canada
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18
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Hauser J, Reissmann A, Sontag TA, Tucha O, Lange KW. Effects of methylphenidate on attention in Wistar rats treated with the neurotoxin N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine (DSP4). J Neural Transm (Vienna) 2017; 124:643-654. [PMID: 28110352 DOI: 10.1007/s00702-017-1679-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Accepted: 01/11/2017] [Indexed: 12/14/2022]
Abstract
The aim of this study was to assess the effects of the neurotoxin N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine (DSP4) on attention in rats as measured using the 5-choice-serial-reaction-time task (5CSRTT) and to investigate whether methylphenidate has effects on DSP4-treated rats. Methylphenidate is a noradrenaline and dopamine reuptake inhibitor and commonly used in the pharmacological treatment of individuals with attention deficit/hyperactivity disorder (ADHD). Wistar rats were trained in the 5CSRTT and treated with one of three doses of DSP4 or saline. Following the DSP4 treatment rats were injected with three doses of methylphenidate or saline and again tested in the 5CSRTT. The treatment with DSP4 caused a significant decline of performance in the number of correct responses and a decrease in response accuracy. A reduction in activity could also be observed. Whether or not the cognitive impairments are due to attention deficits or changes in explorative behaviour or activity remains to be investigated. The treatment with methylphenidate had no beneficial effect on the rats' performance regardless of the DSP4 treatment. In the group without DSP4 treatment, methylphenidate led to a reduction in response accuracy and bidirectional effects in regard to parameters related to attention. These findings support the role of noradrenaline in modulating attention and call for further investigations concerning the effects of methylphenidate on attentional processes in rats.
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Affiliation(s)
- Joachim Hauser
- Department of Experimental Psychology, University of Regensburg, 93040, Regensburg, Germany
| | - Andreas Reissmann
- Department of Experimental Psychology, University of Regensburg, 93040, Regensburg, Germany
| | - Thomas-A Sontag
- Department of Experimental Psychology, University of Regensburg, 93040, Regensburg, Germany
| | - Oliver Tucha
- Department of Clinical and Developmental Neuropsychology, University of Groningen, Groningen, The Netherlands
| | - Klaus W Lange
- Department of Experimental Psychology, University of Regensburg, 93040, Regensburg, Germany.
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Benn A, Robinson ESJ. Differential roles for cortical versus sub-cortical noradrenaline and modulation of impulsivity in the rat. Psychopharmacology (Berl) 2017; 234:255-266. [PMID: 27744551 PMCID: PMC5203835 DOI: 10.1007/s00213-016-4458-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/25/2016] [Accepted: 10/03/2016] [Indexed: 12/31/2022]
Abstract
RATIONALE Atomoxetine is a noradrenaline re-uptake inhibitor licensed for the treatment of adult and childhood attention deficit hyperactivity disorder. Although atomoxetine has established efficacy, the mechanisms which mediate its effects are not well understood. OBJECTIVES In this study, we investigated the role of cortical versus sub-cortical noradrenaline by using focal dopamine beta hydroxylase-saporin-induced lesions, to the prefrontal cortex (n = 16) or nucleus accumbens shell (n = 18). METHODS Healthy animals were tested by using the forced-choice serial reaction time task to assess the impact of the lesion on baseline performance and the response to atomoxetine and the psychostimulant amphetamine. RESULTS We observed attenuation in the efficacy of atomoxetine in animals with lesions to the nucleus accumbens shell, but not the prefrontal cortex. Amphetamine-induced increases in premature responses were potentiated in animals with lesions to the prefrontal cortex, but not the nucleus accumbens shell. CONCLUSIONS These data suggest that noradrenaline in the nucleus accumbens shell plays an important role in the effects of atomoxetine. Under these conditions, prefrontal cortex noradrenaline did not appear to contribute to atomoxetine's effects suggesting a lack of cortical-mediated "top-down" modulation. Noradrenaline in the prefrontal cortex appears to contribute to the modulation of impulsive responding in amphetamine-treated animals, with a loss of noradrenaline associated with potentiation of its effects. These data demonstrate a potential dissociation between cortical and sub-cortical noradrenergic mechanisms and impulse control in terms of the actions of atomoxetine and amphetamine.
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Affiliation(s)
- Abigail Benn
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Biomedical Sciences Building, University Walk, Bristol, BS8 1TD, UK
| | - Emma S J Robinson
- School of Physiology, Pharmacology and Neuroscience, University of Bristol, Biomedical Sciences Building, University Walk, Bristol, BS8 1TD, UK.
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20
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Fizet J, Cassel JC, Kelche C, Meunier H. A review of the 5-Choice Serial Reaction Time (5-CSRT) task in different vertebrate models. Neurosci Biobehav Rev 2016; 71:135-153. [DOI: 10.1016/j.neubiorev.2016.08.027] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Revised: 08/24/2016] [Accepted: 08/26/2016] [Indexed: 01/25/2023]
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21
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Schippers MC, Schetters D, De Vries TJ, Pattij T. Differential effects of the pharmacological stressor yohimbine on impulsive decision making and response inhibition. Psychopharmacology (Berl) 2016; 233:2775-85. [PMID: 27251129 PMCID: PMC4917594 DOI: 10.1007/s00213-016-4337-3] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Accepted: 05/05/2016] [Indexed: 12/28/2022]
Abstract
RATIONALE High levels of impulsivity have been associated with psychiatric disorders such as attention-deficit/hyperactivity disorder (ADHD) and substance abuse. In addition, acute stress is known to exacerbate many psychiatric symptoms in impulse control disorders. OBJECTIVES The purpose of the current study was to investigate the acute effects of the pharmacological stressor yohimbine on response inhibition and impulsive choice. METHODS A group of male rats (n = 12) was trained in the delayed reward task (DRT) to assess impulsive choice. A separate group (n = 10) was trained in the stop-signal task (SST) to measure response inhibition. Upon stable responding, the effects of yohimbine (0, 1.25, 2.5, and 5 mg/kg i.p.) were tested in a Latin square design. RESULTS Acute yohimbine significantly increased the preference for the large and delayed reinforcer in the DRT, indicating a decrease in impulsive choice. On the contrary, the effect size of 1.25 mg/kg yohimbine on stop-signal reaction times correlated negatively with baseline performance, suggesting a baseline-dependent effect on response inhibition as measured in the SST. CONCLUSIONS The current data suggest that the effects of the pharmacological stressor yohimbine on impulse control strongly depend on the type of impulsive behavior. Pharmacological stress decreased impulsive decision making, an observation that is in line with previously published rodent studies. By contrast, the lowest dose of yohimbine revealed a baseline-dependent effect on response inhibition. As such, the effects of yohimbine are largely comparable to the effects of psychostimulants on impulsivity and may support the notion of cross sensitization of stress and psychostimulants.
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Affiliation(s)
- M. C. Schippers
- Department of Anatomy and Neurosciences, Neuroscience Campus Amsterdam, VU University Medical Center, De Boelelaan 1108, 1081 HZ Amsterdam, The Netherlands
| | - D. Schetters
- Department of Anatomy and Neurosciences, Neuroscience Campus Amsterdam, VU University Medical Center, De Boelelaan 1108, 1081 HZ Amsterdam, The Netherlands
| | - T. J. De Vries
- Department of Anatomy and Neurosciences, Neuroscience Campus Amsterdam, VU University Medical Center, De Boelelaan 1108, 1081 HZ Amsterdam, The Netherlands
| | - T. Pattij
- Department of Anatomy and Neurosciences, Neuroscience Campus Amsterdam, VU University Medical Center, De Boelelaan 1108, 1081 HZ Amsterdam, The Netherlands
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Marek GJ, Day M, Hudzik TJ. The Utility of Impulsive Bias and Altered Decision Making as Predictors of Drug Efficacy and Target Selection: Rethinking Behavioral Screening for Antidepressant Drugs. ACTA ACUST UNITED AC 2015; 356:534-48. [DOI: 10.1124/jpet.115.229922] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2015] [Accepted: 12/22/2015] [Indexed: 11/22/2022]
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Abstract
The ability to focus one's attention on important environmental stimuli while ignoring irrelevant stimuli is fundamental to human cognition and intellectual function. Attention is inextricably linked to perception, learning and memory, and executive function; however, it is often impaired in a variety of neuropsychiatric disorders, including Alzheimer's disease, schizophrenia, depression, and attention deficit hyperactivity disorder (ADHD). Accordingly, attention is considered as an important therapeutic target in these disorders. The purpose of this chapter is to provide an overview of the most common behavioral paradigms of attention that have been used in animals (particularly rodents) and to review the literature where these tasks have been employed to elucidate neurobiological substrates of attention as well as to evaluate novel pharmacological agents for their potential as treatments for disorders of attention. These paradigms include two tasks of sustained attention that were developed as rodent analogues of the human Continuous Performance Task (CPT), the Five-Choice Serial Reaction Time Task (5-CSRTT) and the more recently introduced Five-Choice Continuous Performance Task (5C-CPT), and the Signal Detection Task (SDT) which was designed to emphasize temporal components of attention.
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Affiliation(s)
- Patrick M Callahan
- Department of Pharmacology and Toxicology, CB-3545, Georgia Regents University, 1120 Fifteenth Street, Augusta, GA, 30912-2450, USA
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Jupp B, Dalley JW. Convergent pharmacological mechanisms in impulsivity and addiction: insights from rodent models. Br J Pharmacol 2014; 171:4729-66. [PMID: 24866553 PMCID: PMC4209940 DOI: 10.1111/bph.12787] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2014] [Revised: 05/02/2014] [Accepted: 05/12/2014] [Indexed: 01/15/2023] Open
Abstract
Research over the last two decades has widely demonstrated that impulsivity, in its various forms, is antecedent to the development of drug addiction and an important behavioural trait underlying the inability of addicts to refrain from continued drug use. Impulsivity describes a variety of rapidly and prematurely expressed behaviours that span several domains from impaired response inhibition to an intolerance of delayed rewards, and is a core symptom of attention deficit hyperactivity disorder (ADHD) and other brain disorders. Various theories have been advanced to explain how impulsivity interacts with addiction both causally and as a consequence of chronic drug abuse; these acknowledge the strong overlaps in neural circuitry and mechanisms between impulsivity and addiction and the seemingly paradoxical treatment of ADHD with stimulant drugs with high abuse potential. Recent years have witnessed unprecedented progress in the elucidation of pharmacological mechanisms underpinning impulsivity. Collectively, this work has significantly improved the prospect for new therapies in ADHD as well as our understanding of the neural mechanisms underlying the shift from recreational drug use to addiction. In this review, we consider the extent to which pharmacological interventions that target impulsive behaviour are also effective in animal models of addiction. We highlight several promising examples of convergence based on empirical findings in rodent-based studies.
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Affiliation(s)
- B Jupp
- Behavioural and Clinical Neuroscience Institute and Department of Psychology, University of CambridgeCambridge, UK
- Florey Institute of Neuroscience and Mental Health, University of MelbourneParkville, Australia
| | - J W Dalley
- Behavioural and Clinical Neuroscience Institute and Department of Psychology, University of CambridgeCambridge, UK
- Department of Psychiatry, University of CambridgeCambridge, UK
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25
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Asinof SK, Paine TA. The 5-choice serial reaction time task: a task of attention and impulse control for rodents. J Vis Exp 2014:e51574. [PMID: 25146934 DOI: 10.3791/51574] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Abstract
This protocol describes the 5-choice serial reaction time task, which is an operant based task used to study attention and impulse control in rodents. Test day challenges, modifications to the standard task, can be used to systematically tax the neural systems controlling either attention or impulse control. Importantly, these challenges have consistent effects on behavior across laboratories in intact animals and can reveal either enhancements or deficits in cognitive function that are not apparent when rats are only tested on the standard task. The variety of behavioral measures that are collected can be used to determine if other factors (i.e., sedation, motivation deficits, locomotor impairments) are contributing to changes in performance. The versatility of the 5CSRTT is further enhanced because it is amenable to combination with pharmacological, molecular, and genetic techniques.
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The neural and genetic basis of executive function: attention, cognitive flexibility, and response inhibition. Pharmacol Biochem Behav 2013; 123:45-54. [PMID: 23978501 DOI: 10.1016/j.pbb.2013.08.007] [Citation(s) in RCA: 257] [Impact Index Per Article: 23.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2013] [Revised: 07/28/2013] [Accepted: 08/14/2013] [Indexed: 12/11/2022]
Abstract
Executive function is a collection of cognitive processes essential for higher order mental function. Processes involved in executive function include, but are not limited to, working memory, attention, cognitive flexibility, and impulse control. These complex behaviors are largely mediated by prefrontal cortical function but are modulated by dopaminergic, noradrenergic, serotonergic, and cholinergic input. The ability of these neurotransmitter systems to modulate executive function allows for adaptation in cognitive behavior in response to changes in the environment. Because of the important role these neurotransmitter systems play in regulating executive function, changes in these systems can also have a grave impact on executive function. In addition, polymorphisms in genes associated with these neurotransmitters are associated with phenotypic differences in executive function. Understanding how these naturally occurring polymorphisms contribute to different executive function phenotypes will advance basic knowledge of cognition and potentially further understanding and treatment of mental illness that involve changes in executive function. In this review, we will examine the influence of dopamine, norepinephrine, serotonin, and acetylcholine on the following measures of executive function: attention, cognitive flexibility, and impulse control. We will also review the effects of polymorphisms in genes associated with these neurotransmitter systems on these measures of executive function.
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27
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Trillo L, Das D, Hsieh W, Medina B, Moghadam S, Lin B, Dang V, Sanchez MM, De Miguel Z, Ashford JW, Salehi A. Ascending monoaminergic systems alterations in Alzheimer's disease. translating basic science into clinical care. Neurosci Biobehav Rev 2013; 37:1363-79. [PMID: 23707776 DOI: 10.1016/j.neubiorev.2013.05.008] [Citation(s) in RCA: 150] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2013] [Revised: 05/13/2013] [Accepted: 05/16/2013] [Indexed: 01/23/2023]
Abstract
Extensive neuropathological studies have established a compelling link between abnormalities in structure and function of subcortical monoaminergic (MA-ergic) systems and the pathophysiology of Alzheimer's disease (AD). The main cell populations of these systems including the locus coeruleus, the raphe nuclei, and the tuberomamillary nucleus undergo significant degeneration in AD, thereby depriving the hippocampal and cortical neurons from their critical modulatory influence. These studies have been complemented by genome wide association studies linking polymorphisms in key genes involved in the MA-ergic systems and particular behavioral abnormalities in AD. Importantly, several recent studies have shown that improvement of the MA-ergic systems can both restore cognitive function and reduce AD-related pathology in animal models of neurodegeneration. This review aims to explore the link between abnormalities in the MA-ergic systems and AD symptomatology as well as the therapeutic strategies targeting these systems. Furthermore, we will examine possible mechanisms behind basic vulnerability of MA-ergic neurons in AD.
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Affiliation(s)
- Ludwig Trillo
- Department of Physiology, School of Medicine, National University of San Agustin, Arequipa, Peru
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Killeen PR, Russell VA, Sergeant JA. A behavioral neuroenergetics theory of ADHD. Neurosci Biobehav Rev 2013; 37:625-57. [PMID: 23454637 DOI: 10.1016/j.neubiorev.2013.02.011] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2012] [Revised: 02/02/2013] [Accepted: 02/18/2013] [Indexed: 02/02/2023]
Abstract
Energetic insufficiency in neurons due to inadequate lactate supply is implicated in several neuropathologies, including attention-deficit/hyperactivity disorder (ADHD). By formalizing the mechanism and implications of such constraints on function, the behavioral Neuroenergetics Theory (NeT) predicts the results of many neuropsychological tasks involving individuals with ADHD and kindred dysfunctions, and entails many novel predictions. The associated diffusion model predicts that response times will follow a mixture of Wald distributions from the attentive state, and ex-Wald distributions after attentional lapses. It is inferred from the model that ADHD participants can bring only 75-85% of the neurocognitive energy to bear on tasks, and allocate only about 85% of the cognitive resources of comparison groups. Parameters derived from the model in specific tasks predict performance in other tasks, and in clinical conditions often associated with ADHD. The primary action of therapeutic stimulants is to increase norepinephrine in active regions of the brain. This activates glial adrenoceptors, increasing the release of lactate from astrocytes to fuel depleted neurons. The theory is aligned with other approaches and integrated with more general theories of ADHD. Therapeutic implications are explored.
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Affiliation(s)
- Peter R Killeen
- Department of Psychology, Arizona State University, Tempe, AZ 85287-1104, USA.
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Humpston CS, Wood CM, Robinson ESJ. Investigating the roles of different monoamine transmitters and impulse control using the 5-choice serial reaction time task. J Psychopharmacol 2013; 27:213-21. [PMID: 23135241 DOI: 10.1177/0269881112466182] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Previous studies have shown that drugs which block the reuptake of catecholamine neurotransmitters improve impulse control in diseases such as attention deficit hyperactivity disorder (ADHD). Serotonin-specific reuptake inhibitors (SSRI) lack efficacy in ADHD and have been linked to increased suicide risk. The present study investigated drugs with affinity for one or more of the monoamine reuptake transporters using the 5-choice serial reaction time task, a model of attention and impulsivity in rodents. We also tested the effects of the alpha(2)-adreoceptor antagonist, idazoxan and novel antidepressant, agomelatine, which both increase cortical noradrenaline concentrations through non-reuptake mechanisms. Improvements in impulse control were observed with venlafaxine, a serotonin and noradrenaline re-uptake inhibitor (SNRI) but not bupropion (dopamine and noradrenaline re-uptake inhibitor). Sibutramine (SNRI) reduced premature responses by ~50% at the highest dose tested but this was not significant. All three of the SSRIs tested reduced premature responding in a dose-dependent manner, although also slowed response and collection latencies. Neither idazoxan nor agomelatine significantly reduced premature responding, suggesting a lack of efficacy at the doses tested. None of the drugs tested improved attention in this task but sibutramine (SNRI), fluoxetine (SSRI) and paroxetine (SSRI) all increased omissions at the highest dose tested. These data suggest that the SNRIs and SSRIs reduce premature responding but tend to be less specific than noradrenaline specific reuptake inhibitors in this model. SSRIs did not induce any specific impairment in impulse control in this model.
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Affiliation(s)
- Clara S Humpston
- School of Physiology and Pharmacology, University of Bristol, Bristol, BS8 1TD, UK
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Bari A, Robbins TW. Noradrenergic versus dopaminergic modulation of impulsivity, attention and monitoring behaviour in rats performing the stop-signal task: possible relevance to ADHD. Psychopharmacology (Berl) 2013; 230:89-111. [PMID: 23681165 PMCID: PMC3824307 DOI: 10.1007/s00213-013-3141-6] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/19/2013] [Accepted: 04/29/2013] [Indexed: 01/06/2023]
Abstract
RATIONALE Deficient response inhibition is a prominent feature of many pathological conditions characterised by impulsive and compulsive behaviour. Clinically effective doses of catecholamine reuptake inhibitors are able to improve such inhibitory deficits as measured by the stop-signal task (SST) in humans and other animals. However, the precise therapeutic mode of action of these compounds in terms of their relative effects on dopamine (DA) and noradrenaline (NA) systems in prefrontal cortical and striatal regions mediating attention and cognitive control remains unclear. OBJECTIVES We sought to fractionate the effects of global catecholaminergic manipulations on SST performance by using receptor-specific compounds for NA or DA. The results are described in terms of the effects of modulating specific receptor subtypes on various behavioural measures such as response inhibition, perseveration, sustained attention, error monitoring and motivation. RESULTS Blockade of α2-adrenoceptors improved sustained attention and response inhibition, whereas α1 and β1/2 adrenergic receptor antagonists disrupted go performance and sustained attention, respectively. No relevant effects were obtained after targeting DA D1, D2 or D4 receptors, while both a D3 receptor agonist and antagonist improved post-error slowing and compulsive nose-poke behaviour, though generally impairing other task measures. CONCLUSIONS Our results suggest that the use of specific pharmacological agents targeting α2 and β noradrenergic receptors may improve existing treatments for attentional deficits and impulsivity, whereas DA D3 receptors may modulate error monitoring and perseverative behaviour.
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Affiliation(s)
- A. Bari
- Behavioural and Clinical Neuroscience Institute and Department of Psychology, University of Cambridge, Cambridge, CB2 3EB UK ,Department of Neurosciences, Medical University of South Carolina, Ashley Avenue 173, BSB 409, 29425 Charleston, SC USA
| | - T. W. Robbins
- Behavioural and Clinical Neuroscience Institute and Department of Psychology, University of Cambridge, Cambridge, CB2 3EB UK
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Tsutsui-Kimura I, Ohmura Y, Izumi T, Kumamoto H, Yamaguchi T, Yoshida T, Yoshioka M. Milnacipran enhances the control of impulsive action by activating D₁-like receptors in the infralimbic cortex. Psychopharmacology (Berl) 2013; 225:495-504. [PMID: 22892727 DOI: 10.1007/s00213-012-2835-5] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2011] [Accepted: 07/30/2012] [Indexed: 11/27/2022]
Abstract
RATIONALE Elevated impulsivity is often observed in patients with depression. We recently found that milnacipran, an antidepressant and a serotonin/noradrenaline reuptake inhibitor, could enhance impulse control in rats. However, the neural mechanisms underlying the effects of milnacipran on impulsive action remain unclear. Milnacipran increases not only extracellular serotonin and noradrenaline but also dopamine specifically in the medial prefrontal cortex, which is one of the brain regions responsible for impulsive action. OBJECTIVES Our goal was to identify whether D(1)- and/or D(2)-like receptors in the infralimbic cortex (IL), the ventral portion of the medial prefrontal cortex, mediates the milnacipran-enhanced impulse control in a three-choice serial reaction time task. METHODS The rats were bilaterally injected with SCH23390, a selective D(1)-like receptor antagonist (0.3 or 3 ng/side) or eticlopride, a selective D(2)-like receptor antagonist (0.3 or 1 μg/side) into the IL after acute intraperitoneal administration of milnacipran (10 mg/kg). RESULTS Intra-IL SCH23390 injections reversed the milnacipran-enhanced impulse control, whereas injections of eticlopride into the IL failed to block the effects of milnacipran on impulsive action. CONCLUSIONS This is the first report that demonstrates a critical role for D(1)-like receptors of the IL in milnacipran-enhanced control of impulsive action.
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Affiliation(s)
- Iku Tsutsui-Kimura
- Department of Neuropharmacology, Hokkaido University Graduate School of Medicine, N15 W7, Kita-ku, Sapporo 060-8638, Japan
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Atomoxetine modulates spontaneous and sensory-evoked discharge of locus coeruleus noradrenergic neurons. Neuropharmacology 2012; 64:53-64. [PMID: 22820275 DOI: 10.1016/j.neuropharm.2012.07.020] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2012] [Revised: 07/09/2012] [Accepted: 07/11/2012] [Indexed: 11/24/2022]
Abstract
Atomoxetine (ATM) is a potent norepinephrine (NE) uptake inhibitor and increases both NE and dopamine synaptic levels in prefrontal cortex, where it is thought to exert its beneficial effects on attention and impulsivity. At the behavioral level, ATM has been shown to cause improvements on the measures of executive functions, such as response inhibition, working memory and attentional set shifting across different species. However, the exact mechanism of action for ATM's effects on cognition is still not clear. One possible target for the cognitive enhancing effects of ATM is the noradrenergic locus coeruleus (LC), the only source of NE to key forebrain areas such as cerebral cortex and hippocampus. Although it is known that ATM increases NE availability overall by blocking reuptake of NE, the effects of this agent on impulse activity of LC neurons have not been reported. Here, the effect of ATM (0.1-1 mg/kg, ip) on NE-LC neurons was investigated by recording extracellular activity of LC neurons in isoflurane-anesthetized rats. ATM caused a significant decrease of the tonic activity of LC single-units, although leaving intact the sensory-evoked excitatory component of LC phasic response. Moreover, the magnitude of the inhibitory component of LC response to paw stimulation was increased after 1 mg/kg of ATM and its duration was prolonged at 0.3 mg/kg. Together, these effects of ATM produced an increase in the phasic-to-tonic ratio of LC phasic response to sensory stimulation. ATM also modulated the average sensory-evoked local field potential (LFP) and spike-field coherence in LC depending on the dose tested. The lower dose (0.1 mg/kg) significantly decreased early positive and negative components of the sensory-evoked LFP response. Higher doses (0.3-1 mg/kg) initially increased and then decreased the amplitude of components of the evoked fields, whereas the spike-field coherence was enhanced by 1 mg/kg ATM across frequency bands. Finally, coherence between LC fields and EEG signals was generally increased by 1 mg/kg ATM, whereas 0.1 and 0.3 mg/kg respectively decreased and increased coherence values in specific frequency bands. Taken together these results suggest that ATM effects on LC neuronal activity are dose-dependent, with different doses affecting different aspects of LC firing. This modulation of activity of LC-NE neurons may play a role in the cognitive effects of ATM. This article is part of a Special Issue entitled 'Cognitive Enhancers'.
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α₂- and β-adrenoceptors involvement in nortriptyline modulation of auditory sustained attention and impulsivity. Psychopharmacology (Berl) 2012; 222:237-45. [PMID: 22271065 DOI: 10.1007/s00213-012-2635-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2011] [Accepted: 01/01/2012] [Indexed: 10/14/2022]
Abstract
RATIONALE The catecholamine innervation of the prefrontal cortex controls attentional focus and inhibits inappropriate behavioral responses. The mechanism of action with which norepinephrine (NE) reuptake inhibitors modulate these cognitive functions has not been fully investigated. OBJECTIVE We investigated the effect of systemic administration of the NE reuptake blocker nortriptyline (NT) on attention and impulsivity using an auditory sustained attention task. The task was designed to assess impulsive behavior and the maintenance of attentional focus to an auditory stimulus presented at interresponse time durations (IRT) between 5 and 80 s. RESULTS NT (2.0 but not 3.0 mg/kg) improved sustained attention and decreased the percentage of premature responses without changing their latency. To better understand the adrenergic component of NT action, we tested the effect of noradrenergic receptor antagonists alone or together with NT. The α(2)-receptor antagonist yohimbine, the α(1)-receptor antagonist prazosin, or the β-receptor antagonist propranolol alone did not significantly affect attentive performance or premature responses. However, the beneficial effects of NT on sustained attention and premature responses were attenuated by pretreatment with either yohimbine or propranolol. On the contrary, prazosin did not affect the NT-mediated improvement in sustained attention. CONCLUSIONS We conclude that sustained attention displays an inverse U-shaped dependence on NT, mediated-at least in part-by α(2)- and β-adrenoceptors. We speculate that low doses of NT improve performance by maximizing the phasic release of NE, while higher doses of NT would elevate tonic levels of NE, thus producing suboptimal levels of phasically released NE.
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Dalley JW, Roiser JP. Dopamine, serotonin and impulsivity. Neuroscience 2012; 215:42-58. [PMID: 22542672 DOI: 10.1016/j.neuroscience.2012.03.065] [Citation(s) in RCA: 278] [Impact Index Per Article: 23.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2012] [Revised: 03/08/2012] [Accepted: 03/10/2012] [Indexed: 12/17/2022]
Abstract
Impulsive people have a strong urge to act without thinking. It is sometimes regarded as a positive trait but rash impulsiveness is also widely present in clinical disorders such as attention deficit hyperactivity disorder (ADHD), drug dependence, mania, and antisocial behaviour. Contemporary research has begun to make major inroads into unravelling the brain mechanisms underlying impulsive behaviour with a prominent focus on the limbic cortico-striatal systems. With this progress has come the understanding that impulsivity is a multi-faceted behavioural trait involving neurally and psychologically diverse elements. We discuss the significance of this heterogeneity for clinical disorders expressing impulsive behaviour and the pivotal contribution made by the brain dopamine and serotonin systems in the aetiology and treatment of behavioural syndromes expressing impulsive symptoms.
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Affiliation(s)
- J W Dalley
- Behavioural and Clinical Neuroscience Institute and Department of Experimental Psychology, University of Cambridge, Downing Street, Cambridge CB2 3EB, UK. jwd20@cam. ac. uk
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