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de Almeida CC, Neville IS, Hayashi CY, Gomes dos Santos A, Brunoni AR, Teixeira MJ, Paiva WS. Quantification of tumor induced motor cortical plasticity using navigated transcranial magnetic stimulation in patients with adult-type diffuse gliomas. Front Neurosci 2023; 17:1143072. [PMID: 37008212 PMCID: PMC10050360 DOI: 10.3389/fnins.2023.1143072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Accepted: 02/27/2023] [Indexed: 03/17/2023] Open
Abstract
IntroductionThe evaluation of brain plasticity can provide relevant information for the surgical planning of patients with brain tumors, especially when it comes to intrinsic lesions such as gliomas. Neuronavigated transcranial magnetic stimulation (nTMS) is a non-invasive tool capable of providing information about the functional map of the cerebral cortex. Although nTMS presents a good correlation with invasive intraoperative techniques, the measurement of plasticity still needs standardization. The present study evaluated objective and graphic parameters in the quantification and qualification of brain plasticity in adult patients with gliomas in the vicinity of the motor area.MethodsThis is a prospective observational study that included 35 patients with a radiological diagnosis of glioma who underwent standard surgical treatment. nTMS was performed with a focus on the motor area of the upper limbs in both the affected and healthy cerebral hemispheres in all patients to obtain data on motor thresholds (MT) and graphical evaluation by three-dimensional reconstruction and mathematical analysis of parameters related to the location and displacement of the motor centers of gravity (ΔL), dispersion (SDpc) and variability (VCpc) of the points where there was a positive motor response. Data were compared according to the ratios between the hemispheres of each patient and stratified according to the final pathology diagnosis.ResultsThe final sample consisted of 14 patients with a radiological diagnosis of low-grade glioma (LGG), of which 11 were consistent with the final pathology diagnosis. The normalized interhemispheric ratios of ΔL, SDpc, VCpc, and MT were significantly relevant for the quantification of plasticity (p < 0.001). The graphic reconstruction allows the qualitative evaluation of this plasticity.ConclusionThe nTMS was able to quantitatively and qualitatively demonstrate the occurrence of brain plasticity induced by an intrinsic brain tumor. The graphic evaluation allowed the observation of useful characteristics for the operative planning, while the mathematical analysis made it possible to quantify the magnitude of the plasticity.
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Affiliation(s)
- Cesar Cimonari de Almeida
- Division of Neurosurgery, Department of Neurology, University of São Paulo Medical School, São Paulo, Brazil
- Service of Interdisciplinary Neuromodulation, Instituto de Psiquiatria do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
- *Correspondence: Cesar Cimonari de Almeida,
| | - Iuri Santana Neville
- Division of Neurosurgery, Department of Neurology, University of São Paulo Medical School, São Paulo, Brazil
- Service of Interdisciplinary Neuromodulation, Instituto de Psiquiatria do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
- Instituto do Câncer do Estado de São Paulo, Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
| | - Cintya Yukie Hayashi
- Service of Interdisciplinary Neuromodulation, Instituto de Psiquiatria do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
| | - Alexandra Gomes dos Santos
- Division of Neurosurgery, Department of Neurology, University of São Paulo Medical School, São Paulo, Brazil
| | - André Russowsky Brunoni
- Service of Interdisciplinary Neuromodulation, Instituto de Psiquiatria do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
| | - Manoel Jacobsen Teixeira
- Division of Neurosurgery, Department of Neurology, University of São Paulo Medical School, São Paulo, Brazil
| | - Wellingson Silva Paiva
- Division of Neurosurgery, Department of Neurology, University of São Paulo Medical School, São Paulo, Brazil
- Service of Interdisciplinary Neuromodulation, Instituto de Psiquiatria do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, São Paulo, Brazil
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Naz S, Mahmood T, Ahsan F, Rizvi AA, Shamim A. Repercussion of cAMP and EPAC in Memory and Signaling. Drug Res (Stuttg) 2022; 72:65-71. [PMID: 34979574 DOI: 10.1055/a-1657-2464] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
It is well recognized that cyclic adenosine monophosphate (cAMP) signaling within neurons plays a key role in the foundation of long-term memories. Memory storage is the process that demands the movement of signals, neural plasticity, and the molecules which can transfer the signals from the sensory neuron to the dorsal root ganglion (DRG) neurons and later into the temporal region of the brain. The discovery of cAMP in 1958 as the second messenger also had a role in memory formation and other neural aspects. Further, in 1998 the scientists found that cAMP does not just activate protein kinase A (PKA) but also exchange protein directly activated by cAMP (Epac) which has an active role to play in hyperalgesia, memory, and signaling. The cAMP has three targets, hyperpolarization-activated cyclic nucleotide modulated (HCN) channels, protein kinase A (PKA), and exchange protein activated by cAMP (Epac). Different research has exposed that both PKA and HCN channels are significant for long-term memory creation. Epac is a cAMP-dependent guanine nucleotide exchange factor for the small G proteins including Rap1. However, slight information is there about the role of Epac in this process. The effects of cAMP are predominantly imparted by activating protein kinase A (PKA) and the more newly discovered exchange proteins are directly activated by cAMP 1 and 2 (EPAC1 and EPAC2). This review provides an insight regarding the function and role of both of these secondary messengers in memory and nerve signaling.
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Affiliation(s)
- Sabreena Naz
- Department of Pharmacology, Faculty of Pharmacy, Integral University, Lucknow (India)
| | - Tarique Mahmood
- Department of Pharmacology, Faculty of Pharmacy, Integral University, Lucknow (India)
| | - Farogh Ahsan
- Department of Pharmacology, Faculty of Pharmacy, Integral University, Lucknow (India)
| | - Ali Abbas Rizvi
- Department of Pharmacology, Faculty of Pharmacy, Integral University, Lucknow (India)
| | - Arshiya Shamim
- Department of Pharmacology, Faculty of Pharmacy, Integral University, Lucknow (India)
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Kitayama S, Yu Q, King AP, Yoon C, Liberzon I. The gray matter volume of the temporoparietal junction varies across cultures: a moderating role of the dopamine D4 receptor gene (DRD4). Soc Cogn Affect Neurosci 2021; 15:193-202. [PMID: 32300802 DOI: 10.1093/scan/nsaa032] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2019] [Revised: 02/06/2020] [Accepted: 02/28/2020] [Indexed: 01/01/2023] Open
Abstract
Prior work shows that compared to European Americans, East Asians show an enhanced propensity to take the perspective of another person. In the current work, we tested whether this cultural difference might be reflected in the gray matter (GM) volume of the temporoparietal junction (TPJ), a brain region selectively implicated in perspective taking and mentalizing. We also explored whether the cultural difference in the TPJ GM volume might be moderated by dopamine D4 receptor gene (DRD4) exon 3 variable-number tandem repeat polymorphism. Structural magnetic resonance imaging of 66 European Americans and 66 East Asian-born Asians were subjected to voxel-based morphometry. It was observed that the GM volume of the right TPJ was greater among East Asians than among European Americans. Moreover, this cultural difference was significantly more pronounced among carriers of the 7- or 2-repeat allele of DRD4 than among the non-carriers of these alleles. Our findings contribute to the growing evidence that culture can shape the brain.
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Affiliation(s)
- Shinobu Kitayama
- Department of Psychology, University of Michigan, Ann Arbor, MI, USA
| | - Qinggang Yu
- Department of Psychology, University of Michigan, Ann Arbor, MI, USA
| | - Anthony P King
- Department of Psychiatry, University of Michigan, Ann Arbor, MI, USA
| | - Carolyn Yoon
- Ross School of Business, University of Michigan, Ann Arbor, MI, USA
| | - Israel Liberzon
- Department of Psychiatry, Texas A&M College of Medicine, College Station, TX, USA
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Khurana K, Kumar M, Bansal N. Lacidipine Prevents Scopolamine-Induced Memory Impairment by Reducing Brain Oxido-nitrosative Stress in Mice. Neurotox Res 2021; 39:1087-1102. [PMID: 33721210 DOI: 10.1007/s12640-021-00346-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Revised: 02/08/2021] [Accepted: 02/28/2021] [Indexed: 02/06/2023]
Abstract
Cholinergic deficits and oxido-nitrosative stress are consistently associated with Alzheimer's disease (AD). Previous findings indicate that acetylcholine subdues Ca2+ current in the brain. Cholinergic antagonists (e.g., scopolamine) can instigate Ca2+-induced redox imbalance, inflammation, and cell-death pathways leading to AD-type memory impairment. Earlier, several Ca2+-channel blockers (CCB, e.g., dihydropyridine type) or cholinergic enhancers showed promising results in animal models of AD. In the present research, pretreatment effects of lacidipine (L-type CCB) on learning and memory functions were investigated using the scopolamine mouse model of AD. Swiss albino mice (20-25 g) were administered lacidipine (1 and 3 mg/kg) for 14 days. Scopolamine, an anti-muscarinic drug, was given (1 mg/kg) from days 8 to 14. The mice were subjected to elevated plus maze (EPM) and passive-avoidance (PA) paradigms. Bay-K8644 (a Ca2+-channel agonist) was administered before behavioral studies on days 13 and 14. Biochemical parameters of oxidative stress and acetylcholinesterase (AChE) activity were quantified using the whole brain. Behavioral studies showed an increase in transfer latency (TL) in the EPM test and a decrease in step-through latency (STL) in the PA test in scopolamine-administered mice. Scopolamine enhanced the AChE activity and oxidative stress in the brain of mice which resulted in memory impairment. Lacidipine prevented the amnesia against scopolamine and reduced the oxidative stress and AChE activity in the brain of mice. Bay-K8644 attenuated the lacidipine-induced improvement in memory and redox balance in scopolamine-administered mice. Lacidipine can prevent the oxidative stress and improve the cholinergic function in the brain. These properties of lacidipine can mitigate the pathogenesis of AD-type dementia.
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Affiliation(s)
- Kunal Khurana
- I.K. Gujral Punjab Technical University, Kapurthala, Punjab, 144603, India.,Department of Pharmacology, Amar Shaheed Baba Ajeet Singh Jujhar Singh Memorial College of Pharmacy, Bela, Ropar, Punjab, 140111, India
| | - Manish Kumar
- Department of Pharmacology, Amar Shaheed Baba Ajeet Singh Jujhar Singh Memorial College of Pharmacy, Bela, Ropar, Punjab, 140111, India.,Chitkara College of Pharmacy, Chitkara University, Punjab, 140111, India
| | - Nitin Bansal
- Department of Pharmacology, Amar Shaheed Baba Ajeet Singh Jujhar Singh Memorial College of Pharmacy, Bela, Ropar, Punjab, 140111, India. .,Department of Pharmaceutical Sciences, Chaudhary Bansi Lal University (CBLU), Bhiwani, Haryana, 127021, India.
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Quentin R, Awosika O, Cohen LG. Plasticity and recovery of function. HANDBOOK OF CLINICAL NEUROLOGY 2019; 163:473-483. [PMID: 31590747 DOI: 10.1016/b978-0-12-804281-6.00025-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
The frontal lobe plays a crucial role in human motor behavior. It is one of the last areas of the brain to mature, especially the prefrontal regions. After a brief historical perspective on the perceived dichotomy between the view of the brain as a static organ and that of a plastic, constantly changing structure, we discuss the stability/plasticity dilemma including examples of documented cortical reorganization taking place at multiple spatial and temporal scales. We pose that while plasticity is needed for motor learning, stability of the system is necessary for storage and maintenance of memorized skills. We discuss how this plasticity/stability dilemma is resolved along the life span and after a brain injury. We then examine the main challenges that clinicians have to overcome to promote recovery of function in patients with brain lesions, including attempts to use neurostimulation techniques as adjuvant to training-based customary neurorehabilitation.
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Affiliation(s)
- Romain Quentin
- Human Cortical Physiology and Neurorehabilitation Section, NINDS, Bethesda, MD, United States
| | - Oluwole Awosika
- Human Cortical Physiology and Neurorehabilitation Section, NINDS, Bethesda, MD, United States; University of Cincinnati, College of Medicine, Department of Neurology and Rehabilitation Medicine, Cincinnati, OH, United States
| | - Leonardo G Cohen
- Human Cortical Physiology and Neurorehabilitation Section, NINDS, Bethesda, MD, United States.
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Cassel JC. Environment is not trivial! Epilepsia 2019; 60:2020-2022. [PMID: 31584192 DOI: 10.1111/epi.16346] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Accepted: 08/28/2019] [Indexed: 11/30/2022]
Affiliation(s)
- Jean-Christophe Cassel
- Laboratory of Cognitive and Adaptive Neurosciences, University of Strasbourg, Strasbourg, France.,National Center for Scientific Research, Laboratory of Cognitive and Adaptive Neurosciences, Mixed Unit of Research 7364, Strasbourg, France
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Marschner L, Schreurs A, Lechat B, Mogensen J, Roebroek A, Ahmed T, Balschun D. Single mild traumatic brain injury results in transiently impaired spatial long-term memory and altered search strategies. Behav Brain Res 2019; 365:222-230. [DOI: 10.1016/j.bbr.2018.02.040] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2016] [Revised: 10/02/2017] [Accepted: 02/26/2018] [Indexed: 11/16/2022]
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Harper K. Alexander Bain's Mind and Body (1872): An underappreciated contribution to early neuropsychology. JOURNAL OF THE HISTORY OF THE BEHAVIORAL SCIENCES 2019; 55:139-160. [PMID: 30874315 DOI: 10.1002/jhbs.21963] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Alexander Bain (1818-1903) is well known for his two influential textbooks, The senses and the intellect (1855) and The emotions and the will (1859). In comparison, Bain's Mind and body: The theories of their relation (1872) has been of limited interest to historians, and it is here where he presents one of the first neural network models. This paper addresses the historical foundations of Bain's neural network model and explores some of his primary influences. Additionally, this study addresses some of the reasons Bain's Mind and Body did not receive the historical notice his earlier works garnered.
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Affiliation(s)
- Kate Harper
- Spiritual Care and Psychotherapy Program, Martin Luther University College, Wilfrid Laurier University, Waterloo, ON, Canada
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9
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Life-span plasticity of the brain and cognition: From questions to evidence and back. Neurosci Biobehav Rev 2013; 37:2195-200. [DOI: 10.1016/j.neubiorev.2013.10.003] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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10
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Evolutionary Psychology and the Problem of Neural Plasticity. PHILOSOPHY OF BEHAVIORAL BIOLOGY 2012. [DOI: 10.1007/978-94-007-1951-4_11] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
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11
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Popkirov SG, Manahan-Vaughan D. Involvement of the metabotropic glutamate receptor mGluR5 in NMDA receptor-dependent, learning-facilitated long-term depression in CA1 synapses. Cereb Cortex 2010; 21:501-9. [PMID: 20525770 PMCID: PMC3041006 DOI: 10.1093/cercor/bhq093] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Learning-facilitated synaptic plasticity describes the ability of hippocampal synapses to respond with persistent synaptic plasticity to the coupling of weak afferent stimulation, which is subthreshold for the induction of plasticity, with a spatial learning experience. The metabotropic glutamate receptor subtype 5 (mGluR5) is critically involved in enabling the persistency of multiple forms of hippocampal synaptic plasticity. We compared the effects of pharmacological allosteric antagonism of mGluR5 in learning-facilitated plasticity with plasticity that had been induced solely by patterned afferent stimulation of the Schaffer collateral pathway to the CA1 stratum radiatum of adult freely behaving rats. Intracerebroventricular injection of the selective mGluR5 antagonist 2-methyl-6-(phenylethynyl)pyridine (MPEP) had no effect on basal synaptic transmission but significantly prevented both long-term depression (LTD) elicited by electrical stimulation and LTD facilitated by novel object-place configuration learning. NMDA receptor antagonism also prevented learning-facilitated LTD. Habituation to the objects was prevented by MPEP application. Whereas reexposure to the object-place configuration (after 7 days) failed to facilitate LTD in control animals, those who had been treated previously with MPEP expressed LTD, suggesting that inhibition of learning contributed to the initial prevention of LTD. These data support a pivotal role for mGluR5 in both hippocampal LTD and the acquisition of object-place configurations.
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Affiliation(s)
- Stoyan G Popkirov
- Department of Experimental Neurophysiology, Medical Faculty, Ruhr University Bochum, Bochum, Germany
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Park PJ, Bell MA. Variation of telencephalon morphology of the threespine stickleback (Gasterosteus aculeatus) in relation to inferred ecology. J Evol Biol 2010; 23:1261-77. [PMID: 20406344 DOI: 10.1111/j.1420-9101.2010.01987.x] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
We tested the hypothesis that increased telencephalon size has evolved in threespine stickleback fish (Gasterosteus aculeatus) from structurally complex habitats using field-caught samples from one sea-run (ancestral) and 18 ecologically diverse freshwater (descendant) populations. Freshwater habitats ranged from shallow, structurally complex lakes with benthic-foraging stickleback (benthics), to deeper, structurally simple lakes in which stickleback depend more heavily on plankton for prey (generalists). Contrary to our expectations, benthics had smaller telencephala than generalists, but the shape of the telencephalon of the sea-run and benthic populations were more convex laterally. Convex telencephalon shape may indicate enlargement of the dorsolateral region, which is homologous with the tetrapod hippocampus. Telencephalon morphology is also sexually dimorphic, with larger, less convex telencephala in males. Freshwater stickleback from structurally complex habitats have retained the ancestral telencephalon morphology, but populations that feed more in open habitats on plankton have evolved larger, laterally concave telencephala.
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Affiliation(s)
- Peter J Park
- Department of Ecology and Evolution, Stony Brook University, Stony Brook, NY 11794-5245, USA.
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Prenatal lipopolysaccharide reduces motor activity after an immune challenge in adult male offspring. Behav Brain Res 2010; 211:77-82. [PMID: 20226214 DOI: 10.1016/j.bbr.2010.03.009] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2009] [Revised: 02/05/2010] [Accepted: 03/04/2010] [Indexed: 11/23/2022]
Abstract
Prenatal lipopolysaccharide (LPS) exposure causes reproductive, behavioral and neurochemical injuries in both the mother and pups. Previous investigations by our group showed that prenatal LPS administration (100 microg/kg, i.p.) on gestational day 9.5 impaired the male offspring's social behavior in infancy and adulthood. In the present study, we investigated whether these social behavioral changes were associated with motor activity impairment. Male rat pups treated prenatally with LPS or not were tested for reflexological development and open field general activity during infancy. In adulthood, animals were tested for open field general activity, haloperidol-induced catalepsy and apomorphine-induced stereotypy; striatal dopamine levels and turnover were also measured. Moreover, LPS-treated or untreated control pups were challenged with LPS in adulthood and observed for general activity in the open field. In relation to the control group, the motor behavior of prenatally treated male pups was unaffected at basal levels, both in infancy and in adulthood, but decreased general activity was observed in adulthood after an immune challenge. Also, striatal dopamine and metabolite levels were decreased in adulthood. In conclusion, prenatal LPS exposure disrupted the dopaminergic system involved with motor function, but this neurochemical effect was not accompanied by behavioral impairment, probably due to adaptive plasticity processes. Notwithstanding, behavioral impairment was revealed when animals were challenged with LPS, resulting in enhanced sickness behavior.
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Selective involvement of the goldfish lateral pallium in spatial memory. Behav Brain Res 2010; 210:191-201. [PMID: 20178818 DOI: 10.1016/j.bbr.2010.02.031] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2010] [Revised: 02/11/2010] [Accepted: 02/15/2010] [Indexed: 11/20/2022]
Abstract
The involvement of the main pallial subdivisions of the teleost telencephalic pallium in spatial cognition was evaluated in a series of three experiments. The first two compared the effects of lesions selective to the lateral (LP), medial (MP) and dorsal (DP) telencephalic pallium of goldfish, on the retention and the reversal learning of a spatial constancy task which requires the use of allocentric or relational strategies. The results showed that LP lesions produced a selective impairment on the capability of goldfish to solve the spatial task previously learned and on the reversal learning of the same procedure, whereas MP and DP lesions did not produce observable deficits. The third experiment evaluated, by means of the AgNOR stain, learning-dependent changes of the neuronal transcription activity in the pallium of goldfish trained in the spatial constancy task or in a cue version of the same procedure, which only differed on their spatial cognition demands. The results revealed that training in the spatial task produced an increment in the transcriptive activity which was selective to the neurons of the ventral lateral pallium, as indicated by increases in the size of the nucleolar organizing region (NOR), the nucleolar organelles associated with the synthesis of ribosomal proteins. In contrast, training in the cue version did not produced observable changes. These data, revealing a striking functional similarity between the lateral telencephalic pallium of the teleost fish and the amniote hippocampus, provide additional evidence regarding the homology of both structures.
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The Languages of Neurons: An Analysis of Coding Mechanisms by Which Neurons Communicate, Learn and Store Information. ENTROPY 2009. [DOI: 10.3390/e11040782] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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Cai R, Guo F, Zhang J, Xu J, Cui Y, Sun X. Environmental enrichment improves behavioral performance and auditory spatial representation of primary auditory cortical neurons in rat. Neurobiol Learn Mem 2009; 91:366-76. [DOI: 10.1016/j.nlm.2009.01.005] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2008] [Revised: 12/23/2008] [Accepted: 01/09/2009] [Indexed: 11/24/2022]
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Memory modification as an outcome variable in anxiety disorder treatment. J Anxiety Disord 2009; 23:546-56. [PMID: 19117720 DOI: 10.1016/j.janxdis.2008.11.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/10/2008] [Revised: 11/06/2008] [Accepted: 11/06/2008] [Indexed: 01/31/2023]
Abstract
Learning and memory are interdependent processes. Memories are learned, and cumulative learning requires memory. It is generally accepted that learning contributes to psychopathology and consequently to pertinent memory formation. Neuroscience and psychological research have established that memory is an active reconstructive process that is influenced by thoughts, feelings, and behaviors including post-event information. Recent research on the treatment of anxiety disorders using medications (i.e., d-cyclcloserine) to alter neurological systems associated with memory used in conjunction with behavior therapy suggests that memory is part of a central mechanism in the etiology and maintenance of these conditions. The main thesis of this article is that learning-based interventions create new memories that may modify existing ones. This raises the possibility of using such memory modifications to measure intervention outcome. A connectionist context for understanding this phenomenon and informing intervention is provided, with specific reference to post-traumatic stress disorder, obsessive-compulsive disorder, and generalized anxiety disorder. Recommendations for future research examining the role of memory change in treatment outcome are suggested.
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Perez-Garcia G, Meneses A. Memory formation, amnesia, improved memory and reversed amnesia: 5-HT role. Behav Brain Res 2008; 195:17-29. [DOI: 10.1016/j.bbr.2007.11.027] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2007] [Revised: 11/27/2007] [Accepted: 11/27/2007] [Indexed: 11/16/2022]
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Darmopil S, Petanjek Z, Mohammed AH, Bogdanović N. Environmental enrichment alters dentate granule cell morphology in oldest-old rat. J Cell Mol Med 2008; 13:1845-1856. [PMID: 19175692 DOI: 10.1111/j.1582-4934.2008.00560.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
The hippocampus of aged rats shows marked age-related morphological changes that could cause memory deficits. Experimental evidence has established that environmental enrichment attenuates memory deficits in aged rats. We therefore studied whether environmental enrichment produces morphological changes on the dentate granule cells of aged rats. Fifteen male Sprague-Dawley rats, 24 months of age, were randomly distributed in two groups that were housed under standard (n = 7) or enriched (n = 8) environmental conditions for 26 days. Quantitative data of dendritic morphology from dentate gyrus granule cells were obtained on Golgi-Cox stained sections. Environmental enrichment significantly increased the complexity and size of dendritic tree (total number of segments increased by 61% and length by 116%), and spine density (88% increase). There were large interindividual differences within the enriched group, indicating differential individual responses to environmental stimulation. Previous studies in young animals have shown changes produced by environmental enrichment in the morphology of dentate gyrus granule cells. The results of the present study show that environmental enrichment can also produce changes in dentate granule cell morphology in the senescent brain. In conclusion, the hippocampus retains its neuroplastic capacity during aging, and enriched environmental housing conditions can attenuate age-related dendritic regression and synaptic loss, thus preserving memory functions.
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Affiliation(s)
- Sanja Darmopil
- Department for Neurobiology, Caring Science and Society, Division of Clinical Geriatrics, Karolinska Institutet Science Park, Novum Research Park, Stockholm, Sweden.,Croatian Institute for Brain Research, School of Medicine, University of Zagreb, Šalata, Zagreb, Croatia
| | - Zdravko Petanjek
- Croatian Institute for Brain Research, School of Medicine, University of Zagreb, Šalata, Zagreb, Croatia.,Department of Anatomy, School of Medicine, University of Zagreb, Šalata, Zagreb, Croatia
| | - Abdul H Mohammed
- Department for Neurobiology, Caring Science and Society, Division of Clinical Geriatrics, Karolinska Institutet Science Park, Novum Research Park, Stockholm, Sweden.,School of Social Sciences, Växjö University, Växjö, Sweden
| | - Nenad Bogdanović
- Department for Neurobiology, Caring Science and Society, Division of Clinical Geriatrics, Karolinska Institutet Science Park, Novum Research Park, Stockholm, Sweden.,Wyeth Pharmaceutical, Global Medical Team - Neuroscience, Maidenhead, London, UK
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Studying development in the 21 st Century. Behav Brain Sci 2008. [DOI: 10.1017/s0140525x08004202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
AbstractIn this response, we consider four main issues arising from the commentaries to the target article. These include further details of the theory of interactive specialization, the relationship between neuroconstructivism and selectionism, the implications of neuroconstructivism for the notion of representation, and the role of genetics in theories of development. We conclude by stressing the importance of multidisciplinary approaches in the future study of cognitive development and by identifying the directions in which neuroconstructivism can expand in the Twenty-first Century.
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Picchioni M, Matthiasson P, Broome M, Giampietro V, Brammer M, Mathes B, Fletcher P, Williams S, McGuire P. Medial temporal lobe activity at recognition increases with the duration of mnemonic delay during an object working memory task. Hum Brain Mapp 2008; 28:1235-50. [PMID: 17358019 PMCID: PMC6871489 DOI: 10.1002/hbm.20357] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
Object working memory (WM) engages a disseminated neural network, although the extent to which the length of time that data is held in WM influences regional activity within this network is unclear. We used functional magnetic resonance imaging to study a delayed matching to sample task in 14 healthy subjects, manipulating the duration of mnemonic delay. Across all lengths of delay, successful recognition was associated with the bilateral engagement of the inferior and middle frontal gyri and insula, the medial and inferior temporal, dorsal anterior cingulate and the posterior parietal cortices. As the length of time that data was held in WM increased, activation at recognition increased in the medial temporal, medial occipito-temporal, anterior cingulate and posterior parietal cortices. These results confirm the components of an object WM network required for successful recognition, and suggest that parts of this network, including the medial temporal cortex, are sensitive to the duration of mnemonic delay.
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Affiliation(s)
- Marco Picchioni
- King's College London, Institute of Psychiatry, Section of Neuroimaging, London, United Kingdom.
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22
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Historical perspective. Neurobiol Learn Mem 2007. [DOI: 10.1016/b978-012372540-0/50002-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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23
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Hannigan JH, O'leary-Moore SK, Berman RF. Postnatal environmental or experiential amelioration of neurobehavioral effects of perinatal alcohol exposure in rats. Neurosci Biobehav Rev 2006; 31:202-11. [PMID: 16911827 DOI: 10.1016/j.neubiorev.2006.06.019] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2006] [Accepted: 06/12/2006] [Indexed: 11/30/2022]
Abstract
Fetal alcohol spectrum disorders (FASDs) in children are characterized by life-long compromises in learning, memory, and adaptive responses. To date, there are no clinical remedies for the treatment of global fetal alcohol effects, although interventions for specific outcomes are available. Here we review basic research in animal models of perinatal alcohol exposure to assess the potential of global environmental manipulations to ameliorate the neurobehavioral effects associated with FASD. Enhancement of the postnatal environment via neonatal handling, environmental enrichment, or rehabilitative or "therapeutic" motor training, can improve behavioral performance and ameliorate or even eliminate some deficits in perinatal alcohol-exposed rats and mice. While neuroanatomical changes associated with the behavioral improvements have been reported in some models, there generally appears to be a persistent impairment in neuronal plasticity. Such research suggests that it may be possible to manage the postnatal environment or experience of children with FASDs to improve function. It is, however, necessary to consider the difficulties in translating findings from research in animals to the clinic, school or home because sex-, postnatal age- and species-specific differences are critical factors in how specific environments may influence brain development. Continued study of the potential ameliorative effects of neonatal handling, environmental enrichment, and rehabilitative training as "therapies" in animal models will remain a valuable source of information for eventually devising treatments for children with FASDs.
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Affiliation(s)
- John H Hannigan
- Department of Obstetrics & Gynecology, Wayne State University, 275 East Hancock, Detroit, MI 48201, USA.
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24
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Li SC, Brehmer Y, Shing YL, Werkle-Bergner M, Lindenberger U. Neuromodulation of associative and organizational plasticity across the life span: Empirical evidence and neurocomputational modeling. Neurosci Biobehav Rev 2006; 30:775-90. [PMID: 16930705 DOI: 10.1016/j.neubiorev.2006.06.004] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Developmental plasticity is the key mechanism that allows humans and other organisms to modify and adapt to contextual and experiential influences. Thus, reciprocal co-constructive interactions between behavioral and neuronal plasticity play important roles in regulating neurobehavioral development across the life span. This review focuses on behavioral and neuronal evidence of lifespan differences in associative memory plasticity and plasticity of the functional organization of cognitive and cortical processes, as well as the role of the dopaminergic system in modulating such plasticity. Special attention is given to neurocomputational models that help exploring lifespan differences in neuromodulation of neuronal and behavioral plasticity. Simulation results from these models suggest that lifespan changes in the efficacy of neuromodulatory mechanisms may shape associative memory plasticity and the functional organization of neurocognitive processes by affecting the fidelity of neuronal signal transmission, which has consequences for the distinctiveness of neurocognitive representations and the efficacy of distributed neural coding.
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Affiliation(s)
- Shu-Chen Li
- Center for Lifespan Psychology, Max Planck Institute for Human Development, Berlin, Germany.
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25
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Straub VA, Styles BJ, Ireland JS, O'Shea M, Benjamin PR. Central localization of plasticity involved in appetitive conditioning in Lymnaea. Learn Mem 2004; 11:787-93. [PMID: 15537733 PMCID: PMC534707 DOI: 10.1101/lm.77004] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Learning to associate a conditioned (CS) and unconditioned stimulus (US) results in changes in the processing of CS information. Here, we address directly the question whether chemical appetitive conditioning of Lymnaea feeding behavior involves changes in the peripheral and/or central processing of the CS by using extracellular recording techniques to monitor neuronal activity at two stages of the sensory processing pathway. Our data show that appetitive conditioning does not affect significantly the overall CS response of afferent nerves connecting chemosensory structures in the lips and tentacles to the central nervous system (CNS). In contrast, neuronal output from the cerebral ganglia, which represent the first central processing stage for chemosensory information, is enhanced significantly in response to the CS after appetitive conditioning. This demonstrates that chemical appetitive conditioning in Lymnaea affects the central, but not the peripheral processing of chemosensory information. It also identifies the cerebral ganglia of Lymnaea as an important site for neuronal plasticity and forms the basis for detailed cellular studies of neuronal plasticity.
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Affiliation(s)
- Volko A Straub
- Sussex Centre for Neuroscience, Department of Biology and Environmental Science, School of Life Sciences, University of Sussex, Falmer, Brighton, BN1 9QG, United Kingdom.
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26
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Novak MFSX. Fetal-maternal interactions: prenatal psychobiological precursors to adaptive infant development. Curr Top Dev Biol 2004; 59:37-60. [PMID: 14975246 DOI: 10.1016/s0070-2153(04)59002-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/07/2023]
Affiliation(s)
- Matthew F S X Novak
- Section on Comparative Behavioral Genetics, Laboratory of Comparative Ethology, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892, USA
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27
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Richter-Levin G, Akirav I. Emotional tagging of memory formation--in the search for neural mechanisms. ACTA ACUST UNITED AC 2004; 43:247-56. [PMID: 14629927 DOI: 10.1016/j.brainresrev.2003.08.005] [Citation(s) in RCA: 87] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Memory-related areas, such as the hippocampus, should be able to sort out the more significant from the less relevant aspects of an experience in order to transform only the earlier into long-term memory. We have recently suggested the Emotional Tagging concept, according to which the activation of the amygdala in emotionally arousing events mark the experience as important and aids in enhancing synaptic plasticity in other brain regions. Here, we review evidence from both human and animal studies that lend support to the Emotional Tagging hypothesis and to the central role the amygdala may play in its formation. We further speculate on potential neural mechanisms that may underlie emotional tagging. Long-term memory formation is considered to involve lasting alterations in synaptic efficacy, known as synaptic plasticity. It has been suggested that two factors are crucial for obtaining a synapse-specific long-term plasticity: (a) the successful activation of a synapse-specific, protein synthesis-independent tag, and (b) the activation of synapse-non-specific protein synthesis. The activation of protein synthesis can then induce lasting plasticity only in those synapses marked by a tag. Interestingly and relevant to the Emotional Tagging hypothesis, it has been recently shown that the activation of the amygdala could transform transient into long-lasting plasticity. These recent findings seem to fit well with the Emotional Tagging hypothesis. It seems reasonable to assume that the activation of the amygdala triggers neuromodulatory systems, which in turn reduce the threshold for the activation of the synaptic tag, and by this facilitate the transformation of early- into late-phase memory.
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Affiliation(s)
- Gal Richter-Levin
- Department of Psychology and The Brain and Behavior Research Center, University of Haifa, Haifa 31905, Israel.
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28
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29
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Li M, Fleming AS. Differential involvement of nucleus accumbens shell and core subregions in maternal memory in postpartum female rats. Behav Neurosci 2003; 117:426-45. [PMID: 12802872 DOI: 10.1037/0735-7044.117.3.426] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Maternal memory refers to the long-term retention of maternal responsiveness as a consequence of animals' prior experiences with their young. This study examined the relative roles of 2 subregions of the nucleus accumbens (NA; shell and core) in maternal memory in rats. NA shell lesions either before or immediately after a short experience significantly disrupted maternal memory, but lesions after a 24-hr maternal experience had no effect. NA core lesions had no significant impact on maternal memory. Cycloheximide (a protein synthesis inhibitor) at a high dose (25 micrograms/microliter) infused in the NA shell immediately after 1 hr of maternal experience also significantly disrupted maternal memory, whereas infusions in the medial preoptic area had no effect. It was concluded that the NA shell, but not the NA core, is involved in the consolidation of maternal memory.
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Affiliation(s)
- Ming Li
- Department of Psychology, University of Toronto at Mississauga, 3359 Mississauga Road, Mississauga, Ontario L5L 1C6, Canada
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30
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Li SC. Biocultural orchestration of developmental plasticity across levels: the interplay of biology and culture in shaping the mind and behavior across the life span. Psychol Bull 2003; 129:171-94. [PMID: 12696838 DOI: 10.1037/0033-2909.129.2.171] [Citation(s) in RCA: 180] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The author reviews reemerging coconstructive conceptions of development and recent empirical findings of developmental plasticity at different levels spanning several fields of developmental and life sciences. A cross-level dynamic biocultural coconstructive framework is endorsed to understand cognitive and behavioral development across the life span. This framework integrates main conceptions of earlier views into a unifying frame, viewing the dynamics of life span development as occurring simultaneously within different time scales (i.e., moment-to-moment microgenesis, life span ontogeny, and human phylogeny) and encompassing multiple levels (i.e., neurobiological, cognitive, behavioral, and sociocultural). Viewed through this metatheoretical framework, new insights of potential interfaces for reciprocal cultural and experiential influences to be integrated with behavioral genetics and cognitive neuroscience research can be more easily prescribed.
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Affiliation(s)
- Shu-Chen Li
- Max Planck Institute for Human Development, Center for Life Span Psychology, Berlin, Germany.
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31
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Mohammed AH, Zhu SW, Darmopil S, Hjerling-Leffler J, Ernfors P, Winblad B, Diamond MC, Eriksson PS, Bogdanovic N. Environmental enrichment and the brain. PROGRESS IN BRAIN RESEARCH 2002; 138:109-33. [PMID: 12432766 DOI: 10.1016/s0079-6123(02)38074-9] [Citation(s) in RCA: 189] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- A H Mohammed
- Division of Geriatric Medicine, NEUROTEC, Karolinska Institutet, S-141 86 Huddinge, Stockholm, Sweden.
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32
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Tang AC, Zou B. Neonatal exposure to novelty enhances long-term potentiation in CA1 of the rat hippocampus. Hippocampus 2002; 12:398-404. [PMID: 12099490 DOI: 10.1002/hipo.10017] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Exposing rats to an enriched environment over an extended period of time has been shown to enhance hippocampal long-term potentiation (LTP). Whether such prolonged exposure to environmental manipulation is necessary for LTP enhancement and whether the environmentally induced enhancement can persist long after the cessation of the environmental manipulation remain unknown. Using a novelty exposure procedure modified from the method of neonatal handling, we exposed neonatal rats to a non-home environment for 3 min/day during the first 3 weeks of life. We examined the LTP of both population spikes and excitatory postsynaptic potentials (EPSPs), in vitro, in the CA1 of the hippocampus during adulthood (7-8 and 13-14 months of age). We found that both the LTP of population spikes and the LTP of EPSPs were enhanced among animals who experienced neonatal novelty exposure. These results demonstrate that effective environmental enhancement of LTP can be achieved by as brief and as transient a manipulation as a 3-min/day exposure over the first 3 weeks of life. The resulting enhancement can outlast the environmental manipulation by at least 1 year.
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Affiliation(s)
- Akaysha C Tang
- Department of Psychology, University of New Mexico, Albuquerque 87131, USA.
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33
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Larsson F, Winblad B, Mohammed AH. Psychological stress and environmental adaptation in enriched vs. impoverished housed rats. Pharmacol Biochem Behav 2002; 73:193-207. [PMID: 12076739 DOI: 10.1016/s0091-3057(02)00782-7] [Citation(s) in RCA: 141] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
In this study, we report differential behavioural and cognitive effects, as assessed in the open-field and the Morris water maze, following psychological stress in enriched vs. impoverished housed rats. Three stress conditions were evaluated: nonstress, mild stress and powerful stress. Mild stress consisted of exposure to an avoidance box but without shock, while in the powerful stress condition animals were exposed to an electric shock. The results revealed distinct effects in the differentially housed animals. Prior exposure to a mild stress enhanced escape performance in the water maze in enriched but not impoverished animals. However, preexposure to powerful stress negatively affected animals from both housing conditions in the water maze task, but with the enriched animals less affected than impoverished animals. In the open-field test, stress preexposure reduced locomotion counts in both the differentially housed animals. In addition, the results showed that the enrichment effect on emotional reactivity in the open-field is long-lasting and persists even after extensive training and housing in standard laboratory conditions. The results are discussed in relation to the nature of the behavioural and learning differences between the differentially housed animals.
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Affiliation(s)
- Fredrik Larsson
- NEUROTEC, Division of Experimental Geriatric Medicine, Karolinska Institute, Huddinge University Hospital, S-141 86 Huddinge, Sweden
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34
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Archer T, Palomo T, Fredriksson A. Functional deficits following neonatal dopamine depletion and isolation housing: circular water maze acquisition under pre-exposure conditions and motor activity. Neurotox Res 2002; 4:503-522. [PMID: 12754163 DOI: 10.1080/1029842021000022098] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Seven experiments and several behavioural tests were performed to study the effects of housing condition and experimental test conditions upon the behavioural responses and performance of adult rats neonatally treated with 6-hydroxydopamine (6-OHDA, 100 ug intracisternally, i.c.) or with vehicle. Postnatal 6-OHDA induced locomotor and total activity hyperactivity and deficits in navigational learning in a circular swim maze that were blocked by pretreatment with a dopamine (DA) reuptake inhibitor but not a noradrenaline (NA) reuptake inhibitor. Isolation-housing induced deficits in maze learning performance. Grouped housing improved the maze learning performance of 6-OHDA treated rats whereas vehicle treated rats that were isolation housed performed better following latent learning (LL) pre-exposure trials. 6-OHDA treated rats that received both Grouped housing and latent learning trials performed better on the spatial navigation task than those that received Grouped housing but no latent learning or Isolation housing and latent learning. Analysis of habituation quotients indicated marked deficits by 6-OHDA-treated rats suggesting inability to acquire this simple, nonassociative form of learning. Methylphenidate increased all three parameters of motor activity: locomotion, rearing and total activity, in both Isolation-housed and Group-housed rats from 60- to 90- or 120-min post-injection. NDO 008 induced variable and parameter-dependent effects: locomotion was elevated initially in both Isolated and Grouped rats by the compound and then reduced in the Isolated rats only whereas total activity was only elevated initially in the Isolated rats and unaffected in the Grouped rats. Rearing behaviour was reduced markedly, directly post-injection, in the Isolation-housed rats. DA, DOPAC and HVA concentrations in the striatum, nucleus accumbens, olfactory tubercle and midbrain were reduced but most markedly in the striatum. 5-Hydroxytryptamine (5-HT) and 5-hydroxyindole acetic acid (5-HIAA) concentrations were elevated in the striatum, nucleus accumbens (not 5-HIAA) and olfactory tubercle.
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Affiliation(s)
- Trevor Archer
- University of Göteborg, Department of Psychology, Box 500, SE-40530 Göteborg, Sweden
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35
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Abstract
Biophysical, biochemical, and morphological studies have implicated sensory neurons as key sites of plasticity in the formation and retention of the memory of long-term sensitization in Aplysia californica. This study examined the effects of different sensitization training protocols on the structure of sensory neurons mediating the tail-siphon withdrawal reflex. A 4 d training period produced a robust localized outgrowth in these sensory neurons observed 24 hr after the end of training. These changes are consistent with previous results in siphon sensory neurons (Bailey and Chen, 1988a). In contrast, 1 d of sensitization training, which has been shown to effectively induce long-term behavioral sensitization and synaptic facilitation (Frost et al., 1985; Cleary et al., 1998), is not associated with morphological changes in tail sensory neurons at either 24 hr or 4 d after training. Similarly, a single treatment with the growth factor TGF-beta, which also induced facilitation, did not alter sensory neuron morphology. The different effectiveness of the two protocols was not simply a reflection of the number of stimuli presented, because a 1 d massed training protocol did not produce sensitization 24 hr after training, nor did it induce neuronal outgrowth. These results suggest that extensive sensitization training is required to induce neuronal outgrowth in tail sensory neurons, indicating that the memory of long-term sensitization induced by 1 d of training is mechanistically different from that induced by 4 d of training. Moreover, the induction of a form of long-term sensitization associated with neuronal outgrowth does not appear to be a function of the amount of stimulation but does appear to be dependent on the temporal spacing of the stimulation over multiple days.
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36
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Ip EYY, Giza CC, Griesbach GS, Hovda DA. Effects of enriched environment and fluid percussion injury on dendritic arborization within the cerebral cortex of the developing rat. J Neurotrauma 2002; 19:573-85. [PMID: 12042093 DOI: 10.1089/089771502753754055] [Citation(s) in RCA: 83] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
We have recently demonstrated that fluid percussion injury (FPI) sustained early in life prevents the neural plasticity response associated with rearing in an enriched environment (EE). In order to determine if this reduction in plasticity capacity is reflected in alterations in dendritic arborization, the present study examined dendritic changes in response to EE, FPI, and FPI followed by EE. Twenty postnatal day 19-20 rat pups were subjected to FPI or sham injury and were subsequently housed in EE (17 days) or standard conditions. Brains were processed according to the Golgi-Cox method and were analyzed using dendritic density (Sholl) and dendritic branching analyses in frontal, parietal, and occipital cortices. Rearing in EE induced an increase in dendritic density, primarily within the occipital cortex. FPI induced an increase in dendritic density, primarily in regions remote from the injury site, namely contralateral parietal cortex and ipsilateral and contralateral occipital cortex. In injured animals subsequently housed in EE, FPI appeared to inhibit the experience-dependent dendritic density effects of EE. However, an unexpected enhancement of dendritic density was seen in the ipsilateral occipital cortex, indicating a unique response of this region based on its distance-specific sensitivity to injury-induced plasticity and its region-specific sensitivity to experience-dependent plasticity. These results suggest that dendritic changes mediate the anatomical and behavioral changes characteristic of impaired developmental plasticity following FPI, and that these changes are dependent on location within the cerebral cortex.
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Affiliation(s)
- Emily Yu-Yen Ip
- UCLA School of Medicine, Division of Neurosurgery, Los Angeles, California 90025-7039, USA.
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37
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Döbrössy MD, Dunnett SB. The influence of environment and experience on neural grafts. Nat Rev Neurosci 2001; 2:871-9. [PMID: 11733794 DOI: 10.1038/35104055] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- M D Döbrössy
- School of Biosciences, Cardiff University, Museum Avenue Box 911, Cardiff CF10 3US, Wales, UK.
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38
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Tang AC. Neonatal exposure to novel environment enhances hippocampal-dependent memory function during infancy and adulthood. Learn Mem 2001; 8:257-64. [PMID: 11584072 PMCID: PMC311382 DOI: 10.1101/lm.43101] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2001] [Accepted: 08/08/2001] [Indexed: 11/25/2022]
Abstract
Early life experience affects behavior and brain mechanisms. Handling rats during the first three weeks in life can slow age-related cognitive decline (as measured by a hippocampal-dependent spatial learning task) and reduce age-related hippocampal neuron loss. It is not clear, however, whether this early environmental influence on learning is selective for old age or is more general, affecting cognitive development during infancy and young adulthood as well. We briefly exposed neonatal rats to a novel non-home environment for 3 min daily during the first three weeks of life (as a component of the handling method). We found that this brief early environmental manipulation resulted in enhanced hippocampal-dependent learning immediately after weaning and that this learning enhancement persisted into adulthood. These results suggest that subtle early life events can affect cognitive development in all developmental stages and that changes in neural mechanisms other than neuron number are likely to mediate the learning enhancement at multiple developmental stages.
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Affiliation(s)
- A C Tang
- Department of Psychology, University of New Mexico, Albuquerque, New Mexico 87131, USA.
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39
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Ferrari EADM, Toyoda MSS, Faleiros L, Cerutti SM. Plasticidade neural: relações com o comportamento e abordagens experimentais. PSICOLOGIA: TEORIA E PESQUISA 2001. [DOI: 10.1590/s0102-37722001000200011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
As interações entre os estímulos ambientais e as respostas de um organismo determinam as propriedades comportamentais que lhe garantem adaptação a diferentes situações e individualidade comportamental. A interação organismo-ambiente também diferencia e molda os circuitos neurais, que caracterizam a plasticidade e a individualidade neural do organismo. Os estudos sobre plasticidade neural incluem aqueles que manipulam o ambiente e analisam mudanças em circuitos neurais e outros que enfatizam recuperação comportamental após lesão do sistema nervoso. Diferentes questões relativas à fisiologia e ao comportamento, como também à morfologia, à bioquímica e à genética, são abordadas. Este trabalho procura caracterizar diferentes abordagens no estudo da plasticidade neural, indicando as suas relações com a análise do comportamento e da aprendizagem. A investigação dos efeitos que a interação organismo-ambiente produz sobre os sistemas neurais subjacentes ao comportamento é enfatizada como interessante.
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40
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Fineman I, Giza CC, Nahed BV, Lee SM, Hovda DA. Inhibition of neocortical plasticity during development by a moderate concussive brain injury. J Neurotrauma 2000; 17:739-49. [PMID: 11011814 DOI: 10.1089/neu.2000.17.739] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
To determine if a moderate traumatic brain injury (TBI) sustained early in life alters the capacity for developmental plasticity, 17-20-day-old rat pups received a lateral fluid percussion and then reared in an enriched environment for 17 days. Compared to sham-injured controls, this moderate TBI prevented the increase in cortical thickness (1.48 vs. 1.68 mm, p < 0.01) as well as the corresponding enhancement in cognitive performance in the Morris Water Maze (39 vs. 25 trials to criterion, p < 0.05). These injured animals exhibited no significant neuronal degeneration and no evidence of neurologic or motor deficits. These findings strongly support the conclusion that a diffuse brain injury is capable of inhibiting both anatomical and cognitive manifestations of experience-dependent developmental plasticity.
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Affiliation(s)
- I Fineman
- Division of Neurosurgery, UCLA School of Medicine, UCLA Brain Injury Research Center, 90095-7039, USA
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41
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Garcia JA, Zhang D, Estill SJ, Michnoff C, Rutter J, Reick M, Scott K, Diaz-Arrastia R, McKnight SL. Impaired cued and contextual memory in NPAS2-deficient mice. Science 2000; 288:2226-30. [PMID: 10864874 DOI: 10.1126/science.288.5474.2226] [Citation(s) in RCA: 176] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Neuronal PAS domain protein 2 (NPAS2) is a basic helix-loop-helix (bHLH) PAS domain transcription factor expressed in multiple regions of the vertebrate brain. Targeted insertion of a beta-galactosidase reporter gene (lacZ) resulted in the production of an NPAS2-lacZ fusion protein and an altered form of NPAS2 lacking the bHLH domain. The neuroanatomical expression pattern of NPAS2-lacZ was temporally and spatially coincident with formation of the mature frontal association/limbic forebrain pathway. NPAS2-deficient mice were subjected to a series of behavioral tests and were found to exhibit deficits in the long-term memory arm of the cued and contextual fear task. Thus, NPAS2 may serve a dedicated regulatory role in the acquisition of specific types of memory.
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Affiliation(s)
- J A Garcia
- Department of Biochemistry, University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390, USA
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42
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Vargas JP, Rodr¿iguez F, L¿opez JC, Arias JL, Salas C. Spatial learning-induced increase in the argyrophilic nucleolar organizer region of dorsolateral telencephalic neurons in goldfish. Brain Res 2000; 865:77-84. [PMID: 10814734 DOI: 10.1016/s0006-8993(00)02220-4] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Spatial learning and memory related morphological changes in the argyrophilic nucleolar organizer region (AgNOR) of telencephalic neurons in goldfish were quantitatively evaluated by means of AgNOR neurohistochemical stain. The AgNORs and nuclei of nerve cells of two different telencephalic regions of goldfish trained in a spatial task or submitted to a similar non-contingent behavioral procedure (control group) were morphometrically evaluated. Results show that the area of AgNORs in goldfish dorsolateral telencephalic neurons increased significantly in the spatial learning group but not in control group. This effect seems to be highly specific as it did not appear in the dorsolateral area of the control group neither in the dorsomedial area of both groups. As the size of AgNORs in the nerve cell nuclei reflect the level of transcriptive activity, these morphological changes could be revealing increased protein synthesis in goldfish dorsolateral telencephalic neurons related with learning and memory. These findings could contribute to determining the subregions of the teleost telencephalon implicated in spatial learning and could indicate that the AgNOR staining technique would be a useful tool in assesing learning and memory related neuronal activity.
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Affiliation(s)
- J P Vargas
- Laboratorio de Psicobiolog¿ia, Universidad de Sevilla, Avda. San Francisco Javier, s/n, 41005-Sevilla, Spain.
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43
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Abstract
Prenatal exposure to alcohol can result in fetal alcohol syndrome (FAS), characterized by growth retardation, facial dysmorphologies, and a host of neurobehavioral impairments. Neurobehavioral effects in FAS, and in alcohol-related neurodevelopmental disorder, include poor learning and memory, attentional deficits, and motor dysfunction. Many of these behavioral deficits can be modeled in rodents. This paper reviews the literature suggesting that many fetal alcohol effects result, at least in part, from teratogenic effects of alcohol on the hippocampus. Neurobehavioral studies show that animals exposed prenatally to alcohol are impaired in many of the same spatial learning and memory tasks sensitive to hippocampal damage, including T-mazes, the Morris water maze, and the radial arm maze. Direct evidence for hippocampal involvement is provided by neuroanatomical studies of the hippocampus documenting reduced numbers of neurons, lower dendritic spine density on pyramidal neurons, and decreased morphological plasticity after environmental enrichment in rats exposed prenatally to alcohol. Electrophysiological studies also demonstrate changes in synaptic activity in in vitro hippocampal brain slices isolated from prenatal alcohol-exposed animals. Considered together, these observations demonstrate that prenatal exposure to alcohol can result in abnormal hippocampal development and function. Such studies provide a better understanding of neurological deficits associated with FAS in humans, and may also contribute to the development of strategies to ameliorate the effects of prenatal alcohol exposure on behavior.
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Affiliation(s)
- R F Berman
- Department of Neurological Surgery, Center for Neuroscience, University of California at Davis, 95616, USA.
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44
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Filipkowski RK, Rydz M, Berdel B, Morys J, Kaczmarek L. Tactile experience induces c-fos expression in rat barrel cortex. Learn Mem 2000; 7:116-22. [PMID: 10753978 PMCID: PMC311323 DOI: 10.1101/lm.7.2.116] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Understanding gene expression that is responsive to sensory stimulation is central to elucidate molecular mechanisms underlying neuronal plasticity. In this study we demonstrate two new methods of stimulating whiskers that provide major sensory input to rat neocortex. In the first paradigm, animals were placed on the top of a cylinder and their vibrissae were brushed by hand. In the second paradigm, animals were placed for a brief period of time into a new, wired cage resulting in vibrissae stimulation when they explored the new environment. Both approaches induced c-Fos expression in barrel cortex corresponding to the stimulated vibrissae, especially in layer IV. Layers II/III and V/VI also showed c-Fos induction, but there were no detectable changes in layer VIb. The majority of c-Fos-expressing cells are probably not inhibitory neurons, because they do not show parvalbumin staining. Both paradigms, in contrast to the previous methods, are simple to use and do not require anesthesia, restraint of animals, or elaborate experimental setups.
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Affiliation(s)
- R K Filipkowski
- Department of Molecular and Cellular Neurobiology, Nencki Institute, 02-093 Warsaw, Poland
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45
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Hannigan JH, Berman RF. Amelioration of fetal alcohol-related neurodevelopmental disorders in rats: exploring pharmacological and environmental treatments. Neurotoxicol Teratol 2000; 22:103-11. [PMID: 10642119 DOI: 10.1016/s0892-0362(99)00050-1] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Fetal alcohol syndrome (FAS) and alcohol-related neurodevelopmental disorders (ARNDs) in children are characterized by life-long compromises in learning, memory, and adaptive responses. Until the advent of effective prevention measures, it will remain necessary to seek ways to treat the life-long neurobehavioral consequences of prenatal alcohol exposure. To date, there are no clinical remedies to recommend for either specific or global fetal alcohol effects. This article reviews our basic research in animal models that assesses the potential of global environmental manipulations or specific psychopharmacological treatments to ameliorate the neurobehavioral effects of prenatal exposure to alcohol. Postweaning environmental enrichment can improve behavioral performance and ameliorate or even eliminate deficits in prenatal alcohol-exposed rats, although there is persistent impairment in neuronal plasticity, as indicated by the failure of hippocampal pyramidal cells to increase dendrite spine density. Behavioral and neural responses to CNS stimulants differ in rats exposed prenatally to alcohol, although it is not clear that these shifts in dose-response curves would predict benefit to children. Although the present results may sound a note of optimism for the development of effective treatment strategies for children with FAS or ARNDs, it is important to consider that application of these findings in rodents may not be straightforward. We also need to know the critical features of specific environments that influence brain development, and the limits of pharmacotherapy, as well as critical periods of exposure. Continued study of the beneficial, ameliorative effects of environmental enrichment, rehabilitative training, and of pharmacological therapies in animal models, will remain a valuable source of information for eventually devising treatments specific for children with FAS and ARNDs.
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Affiliation(s)
- J H Hannigan
- Department of Obstetrics & Gynecology, Wayne State University School of Medicine, C.S. Mott Center for Human Growth and Development, Detroit, MI 48201, USA.
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46
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Pham TM, Ickes B, Albeck D, Söderström S, Granholm AC, Mohammed AH. Changes in brain nerve growth factor levels and nerve growth factor receptors in rats exposed to environmental enrichment for one year. Neuroscience 1999; 94:279-86. [PMID: 10613518 DOI: 10.1016/s0306-4522(99)00316-4] [Citation(s) in RCA: 187] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
This study examined the effects of long-term differential rearing on levels of brain nerve growth factor, its receptors, and their relationships to cognitive function. Adult rats (two months old) were placed into either enriched or standard housing conditions where they remained for 12 months. Animals from the enriched condition group had significantly higher levels of nerve growth factor in hippocampus, visual and entorhinal cortices compared with animals housed in isolated condition. Immunohistochemical analysis of brain tissue from the medial septal area revealed higher staining intensity and fibre density with both the low-affinity and the high-affinity nerve growth factor receptors. Enriched rats performed better than isolated rats in acquisition of spatial learning and had lower locomotion scores in the open field. These results provide further evidence that experimental stimulation results in increased production of trophic factors and structural reorganization in specific brain regions known to be involved in cognitive function.
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Affiliation(s)
- T M Pham
- Department of Clinical Neuroscience, Occupational Therapy and Elderly Care Research, Karolinska Institute, Huddinge University Hospital, Sweden
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47
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Abstract
Any integrated theory of mind and behavior must address the dynamic interaction between neurobiological and sociocultural systems as possible causes for human action. Newer findings within the behavioral neurosciences have pointed to the brain's exceptional plasticity and flexibility and suggest that one's surroundings, including one's cultural environment, may directly influence the way the human nervous system becomes organized. In this paper, a preliminary connectionist model of culture-brain interaction is proposed in an effort to illustrate the possible contribution of cultural factors to the development of the individual human brain.
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Affiliation(s)
- S Kennepohl
- Department of Psychology, University of Windsor, Windsor, Ontario, Canada.
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48
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Pham TM, Söderström S, Winblad B, Mohammed AH. Effects of environmental enrichment on cognitive function and hippocampal NGF in the non-handled rats. Behav Brain Res 1999; 103:63-70. [PMID: 10475165 DOI: 10.1016/s0166-4328(99)00019-4] [Citation(s) in RCA: 122] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
In this study we examine whether exposure to differential housing after weaning would counteract the effects of postnatal handling (H) or nonhandling (NH) treatment by affecting learning and memory processes in young rats. In addition, we seek to determine if experience in enriched environment would alter hippocampal nerve growth factor (NGF) levels which is one of the factors known to be involved in the regulation of the survival and differentiation of developing basal forebrain neurones. Rats were either exposed to handling treatment, or left undisturbed starting day 1 after birth through day 21. After weaning on day 22, we exposed half of the H rats and half of the NH rats to environmental enrichment for 60 days. The other respective half of the rats was housed in isolated environmental condition (IC). Behavioural measures were taken in open field test, and spatial water maze test. Exposure to enriched environment following postnatal handling and nonhandling increased hippocampal NGF levels, and improved cognitive function in the both groups, with NH rats being more responsive to the effects of enrichment. Our results suggest that environmental enrichment has the potential to prevent or reduce the cognitive and neurochemical deficits in the adult animals associated with nonhandling.
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Affiliation(s)
- T M Pham
- Department of Clinical Neuroscience and Family Medicine, Karolinska Institute, Huddinge Hospital, Sweden
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49
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Soffié M, Hahn K, Terao E, Eclancher F. Behavioural and glial changes in old rats following environmental enrichment. Behav Brain Res 1999; 101:37-49. [PMID: 10342398 DOI: 10.1016/s0166-4328(98)00139-9] [Citation(s) in RCA: 102] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The effects of enriched environment on short-term memory for event durations and on astrocytes (cell density, cell area and % of GFAP immunoreactivity) in hippocampus (Hi), frontal cortex (FC) and corpus callosum (CC) were analysed in old rats housed from weaning to the end of behavioural testing (23 months) either in standard (SC) or in enriched (EC) conditions and in young adults (5 months) all housed in SC. Old SC and EC and young SC rats trained (for 2 months) or not, in a Symbolic Delayed Matching to Sample Task, had to discriminate and remember two (2- and 10-s) signals after short retention intervals. Results confirm the aging-related acquisition and memory deficit. EC reduced the slowness of acquisition, reversed the short-term memory deficit and promoted the retention of the short signal (choose short effect). Old SC naive rats had many hypertrophied astrocytes with long processes in Hi and CC while old EC rats had decreased astrocytes number and size. The behavioural testing resulted in young adult SC rats in Hi and CC, in increased astrocytes number, size and GFAP% and in their decrease in old SC rats. EC and testing have additive effects (very low astrocytes number, size and GFAP%) to compensate for the aging-induced gliosis, mostly in Hi.
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Affiliation(s)
- M Soffié
- Psychobiology Unit, University of Louvain, Louvain-la-Neuve, Belgium.
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50
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Storozhuk M, Castellucci VF. Modulation of cholinergic transmission in the neuronal network of the gill and siphon withdrawal reflex in Aplysia. Neuroscience 1999; 90:291-301. [PMID: 10188955 DOI: 10.1016/s0306-4522(98)00458-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Inhibitory interneurons are important elements of the network underlying the gill and siphon withdrawal reflex in Aplysia, and a large component of this inhibition is cholinergic. In this study, we investigated one key identified cholinergic inhibitory interneuron of the network, neuron L16, and studied some properties of its synaptic transmission and its modulation. We found that a slow inhibitory postsynaptic potential evoked in sensory neurons by L16 has two components. An earlier inhibitory postsynaptic potential component is sensitive to curare (100 microM) and has a reversal potential near the Cl- equilibrium potential (-54.5 mV). A later inhibitory postsynaptic potential component is sensitive to tetraethylammonium (0.5-1 mM); it is decreased by membrane hyperpolarization and becomes undetectable near the K+ equilibrium potential (between -80 and -90 mV). Input to sensory neurons from L16 can be altered by two neuromodulators of the reflex, the small cardioactive peptide and serotonin. Small cardioactive peptide (10 microM) facilitates the connections between L16 and the sensory neurons, while serotonin (5-10 microM) inhibits them. Part of the effect of serotonin on the transmission between L16 and the sensory neurons is due to a postsynaptic mechanism, since responses to acetylcholine application in these cells are decreased by serotonin. These results indicate an additional site of synaptic plasticity in the withdrawal reflex network, the inhibitory cholinergic transmission, by two major neuromodulatory transmitters, small cardioactive peptide and serotonin.
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Affiliation(s)
- M Storozhuk
- Institut de recherches cliniques de Montréal, Centre de recherche en sciences neurologiques, Département de physiologie, Université de Montréal, Québec, Canada
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