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Constant A, Friston KJ, Clark A. Cultivating creativity: predictive brains and the enlightened room problem. Philos Trans R Soc Lond B Biol Sci 2024; 379:20220415. [PMID: 38104605 PMCID: PMC10725762 DOI: 10.1098/rstb.2022.0415] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Accepted: 09/13/2023] [Indexed: 12/19/2023] Open
Abstract
How can one conciliate the claim that humans are uncertainty minimizing systems that seek to navigate predictable and familiar environments with the claim that humans can be creative? We call this the Enlightened Room Problem (ERP). The solution, we suggest, lies not (or not only) in the error-minimizing brain but in the environment itself. Creativity emerges from various degrees of interplay between predictive brains and changing environments: ones that repeatedly move the goalposts for our own error-minimizing machinery. By (co)constructing these challenging worlds, we effectively alter and expand the space within which our own prediction engines operate, and that function as 'exploration bubbles' that enable information seeking, uncertainty minimizing minds to penetrate deeper and deeper into artistic, scientific and engineering space. In what follows, we offer a proof of principle for this kind of environmentally led cognitive expansion. This article is part of the theme issue 'Art, aesthetics and predictive processing: theoretical and empirical perspectives'.
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Affiliation(s)
- Axel Constant
- Department of Informatics, University of Sussex, Brighton, BN1 9RH, UK
| | - Karl John Friston
- Wellcome Trust Centre for Neuroimaging, University College London, London, WC1N 3AR, UK
| | - Andy Clark
- Department of Informatics, University of Sussex, Brighton, BN1 9RH, UK
- Department of Philosophy, and Dept of Informatics, University of Sussex, Brighton, BN1 9RH, UK
- Department of Philosophy, Macquarie University, Sydney, NSW 2109, Australia
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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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Bouras NN, Mack NR, Gao WJ. Prefrontal modulation of anxiety through a lens of noradrenergic signaling. Front Syst Neurosci 2023; 17:1173326. [PMID: 37139472 PMCID: PMC10149815 DOI: 10.3389/fnsys.2023.1173326] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Accepted: 03/30/2023] [Indexed: 05/05/2023] Open
Abstract
Anxiety disorders are the most common class of mental illness in the U.S., affecting 40 million individuals annually. Anxiety is an adaptive response to a stressful or unpredictable life event. Though evolutionarily thought to aid in survival, excess intensity or duration of anxiogenic response can lead to a plethora of adverse symptoms and cognitive dysfunction. A wealth of data has implicated the medial prefrontal cortex (mPFC) in the regulation of anxiety. Norepinephrine (NE) is a crucial neuromodulator of arousal and vigilance believed to be responsible for many of the symptoms of anxiety disorders. NE is synthesized in the locus coeruleus (LC), which sends major noradrenergic inputs to the mPFC. Given the unique properties of LC-mPFC connections and the heterogeneous subpopulation of prefrontal neurons known to be involved in regulating anxiety-like behaviors, NE likely modulates PFC function in a cell-type and circuit-specific manner. In working memory and stress response, NE follows an inverted-U model, where an overly high or low release of NE is associated with sub-optimal neural functioning. In contrast, based on current literature review of the individual contributions of NE and the PFC in anxiety disorders, we propose a model of NE level- and adrenergic receptor-dependent, circuit-specific NE-PFC modulation of anxiety disorders. Further, the advent of new techniques to measure NE in the PFC with unprecedented spatial and temporal resolution will significantly help us understand how NE modulates PFC function in anxiety disorders.
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Britten RA, Fesshaye A, Tidmore A, Blackwell AA. Similar Loss of Executive Function Performance after Exposure to Low (10 cGy) Doses of Single (4He) Ions and the Multi-Ion GCRSim Beam. Radiat Res 2022; 198:375-383. [DOI: 10.1667/rade-22-00022.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Accepted: 06/14/2022] [Indexed: 11/03/2022]
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Liu XH, He Y, Zhang Q, Zeng TS, Zhang JY, Min J, Tian SH, Huang H, Wang W, Dong F, Wang P, Zhang L, Shuang Z, Chen LL, Hu X. Catch-up fat in male adults induces low testosterone and consequently promotes metabolic abnormalities and cognitive impairment. Andrology 2022; 10:871-884. [PMID: 35340131 DOI: 10.1111/andr.13177] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 03/15/2022] [Accepted: 03/16/2022] [Indexed: 11/29/2022]
Abstract
BACKGROUND Catch-up fat in adult (CUFA) caused by rapid nutrition promotion after undernutrition plays an important role in the epidemic of insulin resistance-related diseases in developing societies. Insulin resistance is considered to be closely associated with reduced testosterone levels and cognitive function. However, the effects of CUFA on testosterone levels and cognitive function are unclear in males. OBJECTIVES To investigate the changes of testosterone levels and cognitive function in CUFA in male humans and rats, and explore their probable relationship and mechanisms in rats. MATERIALS AND METHODS The blood testosterone levels, fasting glucose, and blood insulin (FINS) were measured in subpopulation 1 (27 CUFA individuals, 61 controls without CUFA) aged 40-50 years to show the characteristics of sex hormone levels and the metabolic status in CUFA men. Cognitive Flexibility Inventory was conducted in subpopulation 2 (54 CUFA individuals, 214 controls) over 20 years to investigate the associations between sex hormone levels, cognitive function, and CUFA. Male rats (n = 27) were randomly allocated to NC group (normal chow controls), RN group (CUFA, refeeding after caloric restriction), and RT group (RN with testosterone intramuscular injected while refeeding). The blood testosterone levels, intraperitoneal insulin tolerance test (IPITT), and FINS were measured, and the attentional set-shifting task test (ASST) for the assessment of cognitive function was performed in these animals. Insulin signaling pathway, N-methyl-d-aspartate receptors subtype 2A (NR2A) and 2B (NR2B) expression levels were determined in the rat cerebral cortex. RESULTS The total testosterone levels decreased (medium [IQRs], 13.43[9.87-18.96] vs 15.58[13.37-24.96], P = 0.036), and HOMA-IR (Homeostatic Model Assessment for Insulin Resistance) elevated (1.61[1.08-2.33] vs 1.24[0.87-1.87], P = 0.037) in CUFA men in subpopulation 1. Additionally, cognitive impairment was observed in CUFA men in subpopulation 2. Moreover, our results indicated decreases in total and free testosterone levels, elevations in visceral lipid accumulation, FINS, HOMA-IR, blood glucose and the area under the curve (AUC) after IPITT, increases in the number of trials required to achieve the criterion of the first reversal of discrimination (R1) in ASST, and downregulation of IRS-1 mRNA expression, AKT phosphorylation, and the NR2A and NR2B expression in brain tissue in male CUFA rats. Notably, testosterone supplementation improved visceral lipid accumulation and insulin resistance-related metabolic disorders, cognitive dysfunction, decreases in IRS-1 mRNA expression, Akt phosphorylation, and NR2A and NR2B expression in brain tissue in male CUFA rodents. DISCUSSION AND CONCLUSION CUFA was characterized by reduced testosterone levels, metabolic abnormalities, and cognitive dysfunction in males, and testosterone supplementation attenuated these changes, as well as the alteration in insulin signaling and NR2A and NR2B expression in male CUFA rodents. Herein, we tentatively put forward that CUFA in males induces low testosterone, consequently promoting metabolic abnormalities and cognitive impairment probably mediated by defects in insulin signaling and NR2A, NR2B pathway in brain tissue. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Xiao-Huan Liu
- Department of Endocrinology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Hubei provincial Clinical Research Center for Diabetes and Metabolic Disorders, Wuhan, China
| | - Yi He
- Department of Endocrinology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Hubei provincial Clinical Research Center for Diabetes and Metabolic Disorders, Wuhan, China
| | - Qiao Zhang
- Department of Cardiovascular Surgery, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Tian-Shu Zeng
- Department of Endocrinology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Hubei provincial Clinical Research Center for Diabetes and Metabolic Disorders, Wuhan, China
| | - Jiao-Yue Zhang
- Department of Endocrinology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Hubei provincial Clinical Research Center for Diabetes and Metabolic Disorders, Wuhan, China
| | - Jie Min
- Department of Endocrinology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Hubei provincial Clinical Research Center for Diabetes and Metabolic Disorders, Wuhan, China
| | - Sheng-Hua Tian
- Department of Endocrinology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Hubei provincial Clinical Research Center for Diabetes and Metabolic Disorders, Wuhan, China
| | | | | | | | - Ping Wang
- Precision Health Program, Department of Radiology, College of Human Medicine, Michigan State University, East Lansing, Michigan, 48823, USA
| | - Linwei Zhang
- Department of Neurology, China-Japan Friendship Hospital, Beijing, China
| | - Zhenyu Shuang
- Department of Endocrinology, Yueyang People's Hosptial, Yueyang, China
| | - Lu-Lu Chen
- Department of Endocrinology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Hubei provincial Clinical Research Center for Diabetes and Metabolic Disorders, Wuhan, China
| | - Xiang Hu
- Department of Endocrinology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.,Hubei provincial Clinical Research Center for Diabetes and Metabolic Disorders, Wuhan, China
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Burket JA, Matar M, Fesshaye A, Pickle JC, Britten RA. Exposure to Low (≤10 cGy) Doses of 4He Particles Leads to Increased Social Withdrawal and Loss of Executive Function Performance. Radiat Res 2021; 196:345-354. [PMID: 34270762 DOI: 10.1667/rade-20-00251.1] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Accepted: 07/06/2021] [Indexed: 11/03/2022]
Abstract
Astronauts on the planned mission to Mars will be exposed to galactic cosmic radiation (GCR), with proton and He particles accounting (in approximately equal amounts) for ∼75% of the equivalent dose. Exposure to ≤15 cGy of space radiation ions with Z ≥ 15 particles has been shown to impair various executive functions, including attentional set shifting and creative problem-solving in rats. Executive functions also regulate social interactions and mood. Should space radiation exposure alter these executive functions as it does cognitive flexibility, there is the possibility of altered interactions among crew members and team cooperativity during prolonged space exploration. This study characterized the effects of ≤10 cGy 400 MeV/n of 4He particles on cognitive flexibility and social interaction (within freely interacting dyads) in male Wistar rats. Exposure to ≥1 cGy 4He ions induced deficits in the SD and/or CD stages of the attentional set shifting (ATSET) task, as reported after exposure to Z ≥ 15 space radiation ions. Should similar effects occur in astronauts, these data suggest that they would have a reduced ability to identify key events in a new situation and would be more easily distracted by extraneous variables. The irradiated rats were also screened for performance in a task for unconstrained cognitive flexibility (UCFlex), often referred to as creative problem-solving. There was a marked dose-dependent change in UCFlex performance with ∼30% of rats exposed to 10 cGy being unable to solve the problem, while the remaining rats took longer than the sham-irradiated animals to resolve the problem. Importantly, performance in the ATSET test was not indicative of UCFlex performance. From a risk assessment perspective, these findings suggest that a value based on a single behavioral end point may not fully represent the cognitive deficits induced by space radiation, even within the cognitive flexibility domain. Rats that received 5 cGy 4He ion irradiation had a significantly lower level of interaction toward their sham-irradiated partners in a non-anxiogenic (uncaged) dyad interactions study. This is consistent with the social withdrawal previously observed in space radiation-exposed male mice in a three-chamber test. 4He-irradiated rats exhibited a significantly higher incidence and duration of self-grooming, which is even more concerning, given that their dyad partners were able to physically interact with the irradiated rats (i.e., touching/climbing over them). This study has established that exposure of male rats to "light" ions such as He affects multiple executive functions resulting in deficits in both sociability and cognitive flexibility, and possibly affective behavior (reward valuation). Further studies are needed to determine if these space radiation-induced co-morbidities are concomitantly induced within individual rats.
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Affiliation(s)
- Jessica A Burket
- Department of Molecular Biology and Chemistry, Christopher Newport University, Newport News, Virginia 23606
- Department of Program in Neuroscience, Christopher Newport University, Newport News, Virginia 23606
| | - Mona Matar
- National Aeronautics and Space Administration, John H. Glenn Research Center, Cleveland, Ohio 44135
| | - Arriyam Fesshaye
- Department of Radiation Oncology, Eastern Virginia Medical School, Norfolk, Virginia 23507
| | - Jerrah C Pickle
- School of Medicine, Eastern Virginia Medical School, Norfolk, Virginia 23507
| | - Richard A Britten
- Department of Radiation Oncology, Eastern Virginia Medical School, Norfolk, Virginia 23507
- Department of Microbiology and Molecular Cell Biology, Eastern Virginia Medical School, Norfolk, Virginia 23507
- Leroy T Canoles Jr. Cancer Center, Eastern Virginia Medical School, Norfolk, Virginia 23507
- Center for Integrative Neuroinflammatory and Inflammatory diseases, Eastern Virginia Medical School, Norfolk, Virginia 23507
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Britten RA, Wellman LL, Sanford LD. Progressive increase in the complexity and translatability of rodent testing to assess space-radiation induced cognitive impairment. Neurosci Biobehav Rev 2021; 126:159-174. [PMID: 33766676 DOI: 10.1016/j.neubiorev.2021.01.027] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2020] [Revised: 12/15/2020] [Accepted: 01/07/2021] [Indexed: 11/29/2022]
Abstract
Ground-based rodent models have established that space radiation doses (approximately those that astronauts will be exposed to on a mission to Mars) significantly impair performance in a wide range of cognitive tasks. Over the last 40 years there has been a progressive increase in both the complexity and the translatability (to humans) of the cognitive tasks investigated. This review outlines technical and conceptual advances in space radiation rodent testing approaches, along with the advances in analytical approaches, that will make data from ground based studies more amenable to probabilistic risk analysis. While great progress has been made in determining the impact of space radiation on many advanced cognitive processes, challenges remain that need to be addressed prior to commencing deep space missions. A summary of on-going attempts to address existing knowledge gaps and the critical role that rodent studies will have in establishing the impact of space radiation on even more complex (human) cognitive tasks are presented and discussed.
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Affiliation(s)
- Richard A Britten
- Department of Radiation Oncology, Eastern Virginia Medical School, Norfolk, VA, 23507, USA; Department of Microbiology and Molecular Cell Biology, Eastern Virginia Medical School, Norfolk, VA, 23507, USA; Leroy T Canoles Jr. Cancer Center, Eastern Virginia Medical School, Norfolk, VA, 23507, USA; Center for Integrative Neuroscience and Inflammatory Diseases, Eastern Virginia Medical School, Norfolk, VA, 23507, USA.
| | - Laurie L Wellman
- Center for Integrative Neuroscience and Inflammatory Diseases, Eastern Virginia Medical School, Norfolk, VA, 23507, USA; Department of Pathology & Anatomy, Eastern Virginia Medical School, Norfolk, VA, 23507, USA
| | - Larry D Sanford
- Center for Integrative Neuroscience and Inflammatory Diseases, Eastern Virginia Medical School, Norfolk, VA, 23507, USA; Department of Pathology & Anatomy, Eastern Virginia Medical School, Norfolk, VA, 23507, USA
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Beversdorf DQ. The Role of the Noradrenergic System in Autism Spectrum Disorders, Implications for Treatment. Semin Pediatr Neurol 2020; 35:100834. [PMID: 32892961 PMCID: PMC7477304 DOI: 10.1016/j.spen.2020.100834] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Autism spectrum disorder (ASD) is frequently associated with anxiety and hyperarousal. While the pathological changes in the noradrenergic system in ASD are not entirely clear, a number of functional indices of the sympathetic/parasympathetic balance are altered in individuals with ASD, often with a high degree of inter-individual variability. The neuropsychopharmacological effects of α2 agonists and β-adrenergic antagonists make agents targeting these receptors of particular interest. α2 agonists have shown beneficial effects for attention deficit hyperactivity disorder (ADHD) and in other domains in individuals with ASD, but effects on core ASD symptoms are less clear. Case series and single dose psychopharmacological challenges suggest that treatment with β-adrenergic antagonists has beneficial effects on language and social domains. Additionally, psychophysiological markers and premorbid anxiety may predict response to these medications. As a result, β-adrenergic antagonists are currently being utilized in a clinical trial for improving core symptoms as well as anxiety in individuals with ASD.
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Affiliation(s)
- David Q Beversdorf
- Departments of Radiology, Neurology, and Psychological Sciences, and the Thompson Center for Autism and Neurodevelopmental Disorders, University of Missouri-Columbia, Columbia, MO, William and Nancy Thompson Endowed Chair in Radiology..
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Britten RA, Duncan VD, Fesshaye A, Rudobeck E, Nelson GA, Vlkolinsky R. Altered Cognitive Flexibility and Synaptic Plasticity in the Rat Prefrontal Cortex after Exposure to Low (≤15 cGy) Doses of 28Si Radiation. Radiat Res 2020; 193:223-235. [DOI: 10.1667/rr15458.1] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Affiliation(s)
| | | | | | - Emil Rudobeck
- Department of Basic Sciences, Loma Linda University, Loma Linda, California, 92354
| | - Gregory A. Nelson
- Department of Basic Sciences, Loma Linda University, Loma Linda, California, 92354
| | - Roman Vlkolinsky
- Department of Basic Sciences, Loma Linda University, Loma Linda, California, 92354
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Effects of stress on functional connectivity during verbal processing. Brain Imaging Behav 2019; 14:2708-2723. [PMID: 31833016 DOI: 10.1007/s11682-019-00221-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Effects of stress on functional connectivity (FC) in specific language processing regions of the brain during verbal fluency tasks were explored. Roles of gender and serotonin transporter gene polymorphisms (5-HTTLPR), associated with stress susceptibility, were also examined to understand their effect. Forty-five healthy volunteers (Mean age: 19.6 ± 1.6 years; 28 females) participated. Functional magnetic resonance imaging was carried out while participants performed letter and category fluency tasks. These tasks were interposed with the Montreal Imaging Stress Test to induce stress or a no-stress control task. Buccal swabs collected were used to genotype for the presence of polymorphisms on the SLC6A4 gene known to contribute to atypical stress responses. Significant variations in strength of FC were noted between several ROIs, including left inferior frontal gyrus and left middle temporal gyrus. Overall, males showed regional increases in FC strength over long and short distances during task under stress. Additionally, variability in effects of stress on task performance was associated with effects of stress on FC. Results suggest that long distance FC may be strengthened to compensate for additional cognitive load of the stressor but that specific short distance functional connections may be strengthened in a gender specific manner. Additionally, FC may serve as a marker for effects of stress on performance. This is the first study exploring stress effects on language tasks with imaging markers. Future studies will need to explore stress susceptible populations and establish the role of FC as a marker, with implications for targeted therapeutic interventions.
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Britten RA, Duncan VD, Fesshaye AS, Wellman LL, Fallgren CM, Sanford LD. Sleep fragmentation exacerbates executive function impairments induced by protracted low dose rate neutron exposure. Int J Radiat Biol 2019; 97:1077-1087. [PMID: 31724895 DOI: 10.1080/09553002.2019.1694190] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Revised: 10/07/2019] [Accepted: 10/29/2019] [Indexed: 12/20/2022]
Abstract
PURPOSE Astronauts on the planned missions to Mars are expected to have to work more autonomously than on previous missions. Thus mission success may be influenced by the astronauts' ability to respond quickly to unexpected problems, processes that require several executive functions. The purpose of this study was to determine the impact that prolonged low dose and low dose rate exposure to neutrons had on two executive functions, and whether the severity and incidence of cognitive impairment was altered by sleep fragmentation. MATERIALS AND METHODS In this study we assessed the impact that prolonged (six month) low dose rate neutron exposure had on the ability of male Wistar rats to perform in two executive function tasks (i.e. attentional set shifting (ATSET) - a constrained cognitive flexibility task and the UCFlex assay - an unconstrained cognitive flexibility task). In recognition of the fact that astronauts also have to contend with inadequate sleep quantity and quality for much of their time in space, we determined the impact that relatively mild sleep disruption had on the ability to perform in the ATSET test in sham and neutron-irradiated rats. RESULTS Chronic low dose (18 cGy) and dose-rate (1 mGy/day) exposure of rats to mixed neutron and photon over the course of six months resulted in significant impairment of simple discrimination (SD) performance. Should similar effects occur in astronauts subjected to low dose rate exposure to Space Radiation, the impairment of SD performance would result in a decreased ability to identify and learn the 'rules' required to respond to a new task or situation. Analysis of the behavioral data by kernel density estimation revealed that 40% of rats had severe ATSET impairments. This value may be a best-case scenario because exposure to neutrons also adversely impacted performance in the UCFlex task. Furthermore, when the good performing rats were reevaluated after they had been subjected to sleep fragmentation, additional ATSET performance decrements were observed in the set shifting stages of the ATSET test, with only 7.4% of the neutron exposed rats able to successfully perform ATSET under normal and sleep fragmented conditions, as opposed to ∼55% of shams. CONCLUSION Protracted low dose and low dose rate neutron exposures impairs executive functions in a high percentage of rats that were normally rested, however further detriments in performance become evident when the rats are subjected to sleep fragmentation.
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Affiliation(s)
- Richard A Britten
- Department of Radiation Oncology, Eastern Virginia Medical School, Norfolk, VA, USA
- Department of Microbiology and Molecular Cell Biology, Eastern Virginia Medical School, Norfolk, VA, USA
- Leroy T Canoles Jr. Cancer Center, Eastern Virginia Medical School, Norfolk, VA, USA
| | - Vania D Duncan
- Department of Radiation Oncology, Eastern Virginia Medical School, Norfolk, VA, USA
| | - Arriyam S Fesshaye
- Department of Radiation Oncology, Eastern Virginia Medical School, Norfolk, VA, USA
| | - Laurie L Wellman
- Department of Pathology & Anatomy, Eastern Virginia Medical School, Norfolk, VA, USA
| | - Christina M Fallgren
- Department of Environmental and Radiological Health Sciences, Colorado State University, Fort Collins, CO, USA
| | - Larry D Sanford
- Department of Pathology & Anatomy, Eastern Virginia Medical School, Norfolk, VA, USA
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Fei XY, Liu S, Sun YH, Cheng L. Social isolation improves the performance of rodents in a novel cognitive flexibility task. Front Zool 2019; 16:43. [PMID: 31788010 PMCID: PMC6858689 DOI: 10.1186/s12983-019-0339-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2019] [Accepted: 10/09/2019] [Indexed: 01/16/2023] Open
Abstract
Background Social isolation, i.e., the deprivation of social contact, is a highly stressful circumstance that affects behavioral and functional brain development in social animals. Cognitive flexibility, one of the essential executive brain function that facilitates survival problem solving, was reported to be impaired after social isolation rearing. However, most of the previous studies have focused on the constrained aspect of flexibility and little is known about the unconstrained aspect. In the present study, the unconstrained cognitive flexibility of Kunming mice (Mus musculus, Km) reared in isolation was examined by a novel digging task. The exploratory behavior of the mice was also tested utilizing the hole-board and elevated plus maze tests to explain the differences in cognitive flexibility between the mice reared socially and in isolation. Results The results demonstrated that the isolated mice had a higher success rate in solving the novel digging problem and showed a higher rate of exploratory behavior compared with the controls. Linear regression analysis revealed that the time it took the mice to solve the digging problem was negatively associated with exploratory behavior. Conclusions The data suggest that social isolation rearing improves unconstrained cognitive flexibility in mice, which is probably related to an increase in their exploratory behavior. Such effects may reflect the behavioral and cognitive evolutionary adaptations of rodents to survive under complex and stressful conditions.
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Affiliation(s)
- Xin-Yuan Fei
- 1School of Psychology & Key Laboratory of Adolescent Cyberpsycology and Behavior (CCNU) of Ministry of Education, Central China Normal University, Wuhan, 430079 China
| | - Sha Liu
- 1School of Psychology & Key Laboratory of Adolescent Cyberpsycology and Behavior (CCNU) of Ministry of Education, Central China Normal University, Wuhan, 430079 China
| | - Yan-Hong Sun
- 2Fisheries Research Institute, Wuhan Academy of Agricultural Sciences, Wuhan, 430207 China
| | - Liang Cheng
- 1School of Psychology & Key Laboratory of Adolescent Cyberpsycology and Behavior (CCNU) of Ministry of Education, Central China Normal University, Wuhan, 430079 China
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Toledo C, Andrade DC, Díaz HS, Inestrosa NC, Del Rio R. Neurocognitive Disorders in Heart Failure: Novel Pathophysiological Mechanisms Underpinning Memory Loss and Learning Impairment. Mol Neurobiol 2019; 56:8035-8051. [PMID: 31165973 DOI: 10.1007/s12035-019-01655-0] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Accepted: 05/20/2019] [Indexed: 01/01/2023]
Abstract
Heart failure (HF) is a major public health issue affecting more than 26 million people worldwide. HF is the most common cardiovascular disease in elder population; and it is associated with neurocognitive function decline, which represent underlying brain pathology diminishing learning and memory faculties. Both HF and neurocognitive impairment are associated with recurrent hospitalization episodes and increased mortality rate in older people, but particularly when they occur simultaneously. Overall, the published studies seem to confirm that HF patients display functional impairments relating to attention, memory, concentration, learning, and executive functioning compared with age-matched controls. However, little is known about the molecular mechanisms underpinning neurocognitive decline in HF. The present review round step recent evidence related to the possible molecular mechanism involved in the establishment of neurocognitive disorders during HF. We will make a special focus on cerebral ischemia, neuroinflammation and oxidative stress, Wnt signaling, and mitochondrial DNA alterations as possible mechanisms associated with cognitive decline in HF. Also, we provide an integrative mechanism linking pathophysiological hallmarks of altered cardiorespiratory control and the development of cognitive dysfunction in HF patients. Graphical Abstract Main molecular mechanisms involved in the establishment of cognitive impairment during heart failure. Heart failure is characterized by chronic activation of brain areas responsible for increasing cardiac sympathetic load. In addition, HF patients also show neurocognitive impairment, suggesting that the overall mechanisms that underpin cardiac sympathoexcitation may be related to the development of cognitive disorders in HF. In low cardiac output, HF cerebral infarction due to cardiac mural emboli and cerebral ischemia due to chronic or intermittent cerebral hypoperfusion has been described as a major mechanism related to the development of CI. In addition, while acute norepinephrine (NE) release may be relevant to induce neural plasticity in the hippocampus, chronic or tonic release of NE may exert the opposite effects due to desensitization of the adrenergic signaling pathway due to receptor internalization. Enhanced chemoreflex drive is a major source of sympathoexcitation in HF, and this phenomenon elevates brain ROS levels and induces neuroinflammation through breathing instability. Importantly, both oxidative stress and neuroinflammation can induce mitochondrial dysfunction and vice versa. Then, this ROS inflammatory pathway may propagate within the brain and potentially contribute to the development of cognitive impairment in HF through the activation/inhibition of key molecular pathways involved in neurocognitive decline such as the Wnt signaling pathway.
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Affiliation(s)
- C Toledo
- Laboratory of Cardiorespiratory Control, Department of Physiology, Pontificia Universidad Católica de Chile, Santiago, Chile.,Center for Aging and Regeneration (CARE-UC), Pontificia Universidad Católica de Chile, Santiago, Chile
| | - D C Andrade
- Laboratory of Cardiorespiratory Control, Department of Physiology, Pontificia Universidad Católica de Chile, Santiago, Chile.,Centro de investigación en fisiología del ejercicio, Universidad Mayor, Santiago, Chile
| | - H S Díaz
- Laboratory of Cardiorespiratory Control, Department of Physiology, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - N C Inestrosa
- Center for Aging and Regeneration (CARE-UC), Pontificia Universidad Católica de Chile, Santiago, Chile.,Centro de Excelencia en Biomedicina de Magallanes (CEBIMA), Universidad de Magallanes, Punta Arenas, Chile
| | - R Del Rio
- Laboratory of Cardiorespiratory Control, Department of Physiology, Pontificia Universidad Católica de Chile, Santiago, Chile. .,Center for Aging and Regeneration (CARE-UC), Pontificia Universidad Católica de Chile, Santiago, Chile. .,Centro de Excelencia en Biomedicina de Magallanes (CEBIMA), Universidad de Magallanes, Punta Arenas, Chile.
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Beversdorf DQ. Neuropsychopharmacological regulation of performance on creativity-related tasks. Curr Opin Behav Sci 2019; 27:55-63. [PMID: 31106256 PMCID: PMC6519931 DOI: 10.1016/j.cobeha.2018.09.010] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
A number of factors affect performance on tasks associated with creativity. Two pharmacological systems in particularly been identified as important for their impact on creativity, the noradrenergic system and the dopaminergic systems. Furthermore, stress is also established as an important factor impacting performance, most likely mediated by its effects on these neurotransmitter systems. Herein, we review the current literature on the relationships between stress, the noradrenergic system, the dopaminergic system, and other pharmacological factors and their effects on performance on tasks associated with creativity.
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Affiliation(s)
- David Q Beversdorf
- William and Nancy Thompson Endowed Chair in Radiology, University of Missouri
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15
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Lin H, Vartanian O. A Neuroeconomic Framework for Creative Cognition. PERSPECTIVES ON PSYCHOLOGICAL SCIENCE 2018; 13:655-677. [DOI: 10.1177/1745691618794945] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Neuroeconomics is the study of the neurobiological bases of subjective preferences and choices. We present a novel framework that synthesizes findings from the literatures on neuroeconomics and creativity to provide a neurobiological description of creative cognition. We propose that value-based decision-making processes and activity in the locus ceruleus-norepinephrine (LC-NE) neuromodulatory system underlie creative cognition, as well as the large-scale brain network dynamics shown to be associated with creativity. This reconceptualization leads to several falsifiable hypotheses that can further understanding of creativity, decision making, and brain network dynamics.
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Affiliation(s)
- Hause Lin
- Department of Psychology, University of Toronto
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16
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Szabo B, Noble DW, Byrne RW, Tait DS, Whiting MJ. Subproblem learning and reversal of a multidimensional visual cue in a lizard: evidence for behavioural flexibility? Anim Behav 2018. [DOI: 10.1016/j.anbehav.2018.07.018] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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17
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Girotti M, Adler SM, Bulin SE, Fucich EA, Paredes D, Morilak DA. Prefrontal cortex executive processes affected by stress in health and disease. Prog Neuropsychopharmacol Biol Psychiatry 2018; 85:161-179. [PMID: 28690203 PMCID: PMC5756532 DOI: 10.1016/j.pnpbp.2017.07.004] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Revised: 07/01/2017] [Accepted: 07/05/2017] [Indexed: 11/23/2022]
Abstract
Prefrontal cortical executive functions comprise a number of cognitive capabilities necessary for goal directed behavior and adaptation to a changing environment. Executive dysfunction that leads to maladaptive behavior and is a symptom of psychiatric pathology can be instigated or exacerbated by stress. In this review we survey research addressing the impact of stress on executive function, with specific focus on working memory, attention, response inhibition, and cognitive flexibility. We then consider the neurochemical pathways underlying these cognitive capabilities and, where known, how stress alters them. Finally, we review work exploring potential pharmacological and non-pharmacological approaches that can ameliorate deficits in executive function. Both preclinical and clinical literature indicates that chronic stress negatively affects executive function. Although some of the circuitry and neurochemical processes underlying executive function have been characterized, a great deal is still unknown regarding how stress affects these processes. Additional work focusing on this question is needed in order to make progress on developing interventions that ameliorate executive dysfunction.
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Affiliation(s)
- Milena Girotti
- Department of Pharmacology, Center for Biomedical Neuroscience, UT Health San Antonio, 7703 Floyd Curl Dr, San Antonio, TX 78229, USA.
| | - Samantha M Adler
- Department of Pharmacology, Center for Biomedical Neuroscience, UT Health San Antonio, 7703 Floyd Curl Dr, San Antonio, TX 78229, USA
| | - Sarah E Bulin
- Department of Pharmacology, Center for Biomedical Neuroscience, UT Health San Antonio, 7703 Floyd Curl Dr, San Antonio, TX 78229, USA
| | - Elizabeth A Fucich
- Department of Pharmacology, Center for Biomedical Neuroscience, UT Health San Antonio, 7703 Floyd Curl Dr, San Antonio, TX 78229, USA
| | - Denisse Paredes
- Department of Pharmacology, Center for Biomedical Neuroscience, UT Health San Antonio, 7703 Floyd Curl Dr, San Antonio, TX 78229, USA
| | - David A Morilak
- Department of Pharmacology, Center for Biomedical Neuroscience, UT Health San Antonio, 7703 Floyd Curl Dr, San Antonio, TX 78229, USA
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Frye RE, Wynne R, Rose S, Slattery J, Delhey L, Tippett M, Kahler SG, Bennuri SC, Melnyk S, Sequeira JM, Quadros EV. Thyroid dysfunction in children with autism spectrum disorder is associated with folate receptor α autoimmune disorder. J Neuroendocrinol 2017; 29. [PMID: 28199771 DOI: 10.1111/jne.12461] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2015] [Revised: 02/07/2017] [Accepted: 02/09/2017] [Indexed: 12/11/2022]
Abstract
Folate receptor α (FRα) autoantibodies (FRAAs) are prevalent in autism spectrum disorder (ASD). FRAAs disrupt folate transport across the blood-brain barrier by binding to the FRα. Thyroid dysfunction is frequently found in children with ASD. We measured blocking and binding FRAAs and thyroid-stimulating hormone (TSH), free thyroxine (T4) (FT4), total triiodothyronine (T3) (TT3), reverse T3 (rT3), thyroid-releasing hormone (TRH) and other metabolites in 87 children with ASD, 84 of whom also underwent behaviour and cognition testing and in 42 of whom FRAAs, TSH and FT4 were measured at two time points. To better understand the significance of the FRα in relation to thyroid development, we examined FRα expression on prenatal and postnatal thyroid. TSH, TT3 and rT3 were above the normal range in 7%, 33% and 51% of the participants and TRH was below the normal range in 13% of the participants. FT4 was rarely outside the normal range. TSH concentration was positively and the FT4/TSH, TT3/TSH and rT3/TSH ratios were inversely related to blocking FRAA titres. On repeated measurements, changes in TSH and FT4/TSH ratio were found to correspond to changes in blocking FRAA titres. TSH and the FT4/TSH, TT3/TSH and rT3/TSH ratios were related to irritability on the Aberrant Behavior Checklist and several scales of the Social Responsiveness Scale (SRS), whereas TT3 was associated with SRS subscales and TRH was related to Vineland Adaptive Behavior Scale subscales. The thyroid showed significant FRα expression during the early prenatal period, although expression decreased significantly in later gestation and postnatal thyroid tissue. The results of the present study suggest that thyroid dysfunction in ASD may be related to blocking FRAA. The high expression of FRα in the early foetal thyroid suggests that foetal and neonatal exposure to maternal FRAAs could affect the development of the thyroid and may contribute to the pathology in ASD.
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Affiliation(s)
- R E Frye
- Department of Pediatrics, Arkansas Children's Research Institute, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - R Wynne
- Department of Pediatrics, Arkansas Children's Research Institute, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - S Rose
- Department of Pediatrics, Arkansas Children's Research Institute, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - J Slattery
- Department of Pediatrics, Arkansas Children's Research Institute, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - L Delhey
- Department of Pediatrics, Arkansas Children's Research Institute, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - M Tippett
- Department of Pediatrics, Arkansas Children's Research Institute, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - S G Kahler
- Department of Pediatrics, Arkansas Children's Research Institute, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - S C Bennuri
- Department of Pediatrics, Arkansas Children's Research Institute, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - S Melnyk
- Department of Pediatrics, Arkansas Children's Research Institute, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - J M Sequeira
- Department of Medicine, State University of New York - Downstate Medical Center, Brooklyn, NY, USA
| | - E V Quadros
- Department of Medicine, State University of New York - Downstate Medical Center, Brooklyn, NY, USA
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20
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Atzori M, Cuevas-Olguin R, Esquivel-Rendon E, Garcia-Oscos F, Salgado-Delgado RC, Saderi N, Miranda-Morales M, Treviño M, Pineda JC, Salgado H. Locus Ceruleus Norepinephrine Release: A Central Regulator of CNS Spatio-Temporal Activation? Front Synaptic Neurosci 2016; 8:25. [PMID: 27616990 PMCID: PMC4999448 DOI: 10.3389/fnsyn.2016.00025] [Citation(s) in RCA: 86] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2016] [Accepted: 08/05/2016] [Indexed: 12/22/2022] Open
Abstract
Norepinephrine (NE) is synthesized in the Locus Coeruleus (LC) of the brainstem, from where it is released by axonal varicosities throughout the brain via volume transmission. A wealth of data from clinics and from animal models indicates that this catecholamine coordinates the activity of the central nervous system (CNS) and of the whole organism by modulating cell function in a vast number of brain areas in a coordinated manner. The ubiquity of NE receptors, the daunting number of cerebral areas regulated by the catecholamine, as well as the variety of cellular effects and of their timescales have contributed so far to defeat the attempts to integrate central adrenergic function into a unitary and coherent framework. Since three main families of NE receptors are represented-in order of decreasing affinity for the catecholamine-by: α2 adrenoceptors (α2Rs, high affinity), α1 adrenoceptors (α1Rs, intermediate affinity), and β adrenoceptors (βRs, low affinity), on a pharmacological basis, and on the ground of recent studies on cellular and systemic central noradrenergic effects, we propose that an increase in LC tonic activity promotes the emergence of four global states covering the whole spectrum of brain activation: (1) sleep: virtual absence of NE, (2) quiet wake: activation of α2Rs, (3) active wake/physiological stress: activation of α2- and α1-Rs, (4) distress: activation of α2-, α1-, and β-Rs. We postulate that excess intensity and/or duration of states (3) and (4) may lead to maladaptive plasticity, causing-in turn-a variety of neuropsychiatric illnesses including depression, schizophrenic psychoses, anxiety disorders, and attention deficit. The interplay between tonic and phasic LC activity identified in the LC in relationship with behavioral response is of critical importance in defining the short- and long-term biological mechanisms associated with the basic states postulated for the CNS. While the model has the potential to explain a large number of experimental and clinical findings, a major challenge will be to adapt this hypothesis to integrate the role of other neurotransmitters released during stress in a centralized fashion, like serotonin, acetylcholine, and histamine, as well as those released in a non-centralized fashion, like purines and cytokines.
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Affiliation(s)
- Marco Atzori
- Neurobiology of Stress Laboratory, Facultad de Ciencias, Universidad Autónoma de San Luis PotosíSan Luis Potosí, Mexico; School for Behavior and Brain Sciences, University of Texas at DallasRichardson, TX, USA
| | - Roberto Cuevas-Olguin
- Neurobiology of Stress Laboratory, Facultad de Ciencias, Universidad Autónoma de San Luis Potosí San Luis Potosí, Mexico
| | - Eric Esquivel-Rendon
- Neurobiology of Stress Laboratory, Facultad de Ciencias, Universidad Autónoma de San Luis Potosí San Luis Potosí, Mexico
| | | | - Roberto C Salgado-Delgado
- Neurobiology of Stress Laboratory, Facultad de Ciencias, Universidad Autónoma de San Luis Potosí San Luis Potosí, Mexico
| | - Nadia Saderi
- Neurobiology of Stress Laboratory, Facultad de Ciencias, Universidad Autónoma de San Luis Potosí San Luis Potosí, Mexico
| | - Marcela Miranda-Morales
- Neurobiology of Stress Laboratory, Facultad de Ciencias, Universidad Autónoma de San Luis Potosí San Luis Potosí, Mexico
| | - Mario Treviño
- Laboratory of Cortical Plasticity and Learning, Universidad de Guadalajara Guadalajara, Mexico
| | - Juan C Pineda
- Electrophysiology Laboratory, Centro de Investigaciones Regionales "Dr. Hideyo Noguchi", Universidad Autónoma de Yucatán Mérida, Mexico
| | - Humberto Salgado
- Electrophysiology Laboratory, Centro de Investigaciones Regionales "Dr. Hideyo Noguchi", Universidad Autónoma de Yucatán Mérida, Mexico
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