1
|
Gutiérrez-Menéndez A, Méndez M, Arias JL. Learning and metabolic brain differences between juvenile male and female rats in the execution of different training regimes of a spatial memory task. Physiol Behav 2023; 267:114203. [PMID: 37086830 DOI: 10.1016/j.physbeh.2023.114203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 04/17/2023] [Accepted: 04/19/2023] [Indexed: 04/24/2023]
Abstract
Spatial memory is responsible for encoding spatial information to form a path, storing this mental representation, and evaluating and recovering spatial configurations to find a target location in the environment. It is mainly supported by the hippocampus and its interaction with other structures, such as the prefrontal cortex, and emerges in rodents around postnatal day (PND) 20. Sex differences in spatial tasks have been found in adults, with a supposedly better performance in males. However, few studies have examined sex differences in orientation throughout postnatal development. This study aimed to analyse the performance of juvenile (PND 23) male (n=18) and female (n=21) Wistar rats in a spatial reference memory task in the Morris water maze (MWM) with two different training regimes in the acquisition phase, and their subjacent metabolic brain activity. Based on sex, subjects were assigned to two different groups: one that performed four learning trials per day (n=9 males and n=8 females) and the other that was submitted to two trials per day (n=9 males and n=13 females). After the behavioural protocols, metabolic activity was evaluated using cytochrome c oxidase histochemistry. Results showed no metabolic brain or behavioural differences in the four-trial protocol performance, in which both sexes reached the learning criterion on the fourth day. By contrast, the two-trial protocol revealed an advantage for females, who reached the learning criterion on day four, whereas males needed more training and succeeded on day six. The female group showed lower metabolic activity than the male group in the cingulate and prelimbic cortex. These results suggest a faster consolidation process in the female group than the male group. Further research is needed to understand sex differences in spatial memory at early stages.
Collapse
Affiliation(s)
- Alba Gutiérrez-Menéndez
- Laboratory of Neuroscience, Department of Psychology, University of Oviedo, Plaza Feijóo, s/n, E-33003, Oviedo, Spain; Instituto de Neurociencias del Principado de Asturias (INEUROPA), Oviedo, Spain; Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), Oviedo, Spain.
| | - Marta Méndez
- Laboratory of Neuroscience, Department of Psychology, University of Oviedo, Plaza Feijóo, s/n, E-33003, Oviedo, Spain; Instituto de Neurociencias del Principado de Asturias (INEUROPA), Oviedo, Spain; Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), Oviedo, Spain
| | - Jorge L Arias
- Laboratory of Neuroscience, Department of Psychology, University of Oviedo, Plaza Feijóo, s/n, E-33003, Oviedo, Spain; Instituto de Neurociencias del Principado de Asturias (INEUROPA), Oviedo, Spain; Instituto de Investigación Sanitaria del Principado de Asturias (ISPA), Oviedo, Spain
| |
Collapse
|
2
|
Puig-Parnau I, Garcia-Brito S, Vila-Soles L, Riberas A, Aldavert-Vera L, Segura-Torres P, Kádár E, Huguet G. Intracranial Self-stimulation of the Medial Forebrain Bundle Ameliorates Memory Disturbances and Pathological Hallmarks in an Alzheimer's Disease Model by Intracerebral Administration of Amyloid-β in Rats. Neuroscience 2023; 512:16-31. [PMID: 36646411 DOI: 10.1016/j.neuroscience.2023.01.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Revised: 01/04/2023] [Accepted: 01/05/2023] [Indexed: 01/15/2023]
Abstract
No curative or fully effective treatments are currently available for Alzheimer's disease (AD), the most common form of dementia. Electrical stimulation of deep brain areas has been proposed as a novel neuromodulatory therapeutic approach. Previous research from our lab demonstrates that intracranial self-stimulation (ICSS) targeting medial forebrain bundle (MFB) facilitates explicit and implicit learning and memory in rats with age or lesion-related memory impairment. At a molecular level, MFB-ICSS modulates the expression of plasticity and neuroprotection-related genes in memory-related brain areas. On this basis, we suggest that MFB could be a promising stimulation target for AD treatment. In this study, we aimed to assess the effects of MFB-ICSS on both explicit memory as well as the levels of neuropathological markers ptau and drebrin (DBN) in memory-related areas, in an AD rat model obtained by Aβ icv-injection. A total of 36 male rats were trained in the Morris water maze on days 26-30 after Aβ injection and tested on day 33. Results demonstrate that this Aβ model displayed spatial memory impairment in the retention test, accompanied by changes in the levels of DBN and ptau in lateral entorhinal cortex and hippocampus, resembling pathological alterations in early AD. Administration of MFB-ICSS treatment consisting of 5 post-training sessions to AD rats managed to reverse the memory deficits as well as the alteration in ptau and DBN levels. Thus, this paper reports both cognitive and molecular effects of a post-training reinforcing deep brain stimulation procedure in a sporadic AD model for the first time.
Collapse
Affiliation(s)
| | - Soleil Garcia-Brito
- Universitat Autònoma de Barcelona, Unitat Psicobiologia, Institut de Neurociències, 08193 Bellaterra, Barcelona, Spain
| | - Laia Vila-Soles
- Universitat Autònoma de Barcelona, Unitat Psicobiologia, Institut de Neurociències, 08193 Bellaterra, Barcelona, Spain
| | - Andrea Riberas
- Universitat de Girona, Departament de Biologia, 17003 Girona, Spain
| | - Laura Aldavert-Vera
- Universitat Autònoma de Barcelona, Unitat Psicobiologia, Institut de Neurociències, 08193 Bellaterra, Barcelona, Spain
| | - Pilar Segura-Torres
- Universitat Autònoma de Barcelona, Unitat Psicobiologia, Institut de Neurociències, 08193 Bellaterra, Barcelona, Spain.
| | - Elisabet Kádár
- Universitat de Girona, Departament de Biologia, 17003 Girona, Spain
| | - Gemma Huguet
- Universitat de Girona, Departament de Biologia, 17003 Girona, Spain.
| |
Collapse
|
3
|
Vila-Solés L, García-Brito S, Aldavert-Vera L, Kádár E, Huguet G, Morgado-Bernal I, Segura-Torres P. Protocol to assess rewarding brain stimulation as a learning and memory modulating treatment: Comparison between self-administration and experimenter-administration. Front Behav Neurosci 2022; 16:1046259. [PMID: 36590922 PMCID: PMC9798322 DOI: 10.3389/fnbeh.2022.1046259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2022] [Accepted: 11/25/2022] [Indexed: 12/23/2022] Open
Abstract
Intracranial electrical self-stimulation (ICSS) is a useful procedure in animal research. This form of administration ensures that areas of the brain reward system (BRS) are being functionally activated, since the animals must perform an operant response to self-administer an electrical stimulus. Rewarding post-training ICSS of the medial forebrain bundle (MFB), an important system of the BRS, has been shown to consistently improve rats' acquisition and retention in several learning tasks. In the clinical setting, deep brain stimulation (DBS) of different targets is currently being used to palliate the memory impairment that occurs in some neurodegenerative diseases. However, the stimulation of the MFB has only been used to treat emotional alterations, not memory disorders. Since DBS stimulation treatments in humans are exclusively administered by external sources, studies comparing the efficacy of that form of application to a self-administered stimulation are key to the translationality of ICSS. This protocol compares self-administered (ICSS) and experimenter-administered (EAS) stimulation of the MFB on the spatial Morris Water Maze task (MWM). c-Fos immunohistochemistry procedure was carried out to evaluate neural activation after retention. Results show that the stimulation of the MFB improves the MWM task regardless of the form of administration, although some differences in c-Fos expression were found. Present results suggest that MFB-ICSS is a valid animal model to study the effects of MFB electrical stimulation on memory, which could guide clinical applications of DBS. The present protocol is a useful guide for establishing ICSS behavior in rats, which could be used as a learning and memory-modulating treatment.
Collapse
Affiliation(s)
- Laia Vila-Solés
- Departament de Psicobiologia i de Metodologia de les Ciències de la Salut, Institut de Neurociències, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Soleil García-Brito
- Departament de Psicobiologia i de Metodologia de les Ciències de la Salut, Institut de Neurociències, Universitat Autònoma de Barcelona, Barcelona, Spain,*Correspondence: Soleil García-Brito,
| | - Laura Aldavert-Vera
- Departament de Psicobiologia i de Metodologia de les Ciències de la Salut, Institut de Neurociències, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Elisabet Kádár
- Departament de Biologia, Universitat de Girona, Girona, Spain
| | - Gemma Huguet
- Departament de Biologia, Universitat de Girona, Girona, Spain
| | - Ignacio Morgado-Bernal
- Departament de Psicobiologia i de Metodologia de les Ciències de la Salut, Institut de Neurociències, Universitat Autònoma de Barcelona, Barcelona, Spain
| | - Pilar Segura-Torres
- Departament de Psicobiologia i de Metodologia de les Ciències de la Salut, Institut de Neurociències, Universitat Autònoma de Barcelona, Barcelona, Spain
| |
Collapse
|
4
|
Palaus M, Viejo-Sobera R, Redolar-Ripoll D, Marrón EM. Cognitive Enhancement via Neuromodulation and Video Games: Synergistic Effects? Front Hum Neurosci 2020; 14:235. [PMID: 32636739 PMCID: PMC7319101 DOI: 10.3389/fnhum.2020.00235] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2020] [Accepted: 05/28/2020] [Indexed: 12/18/2022] Open
Abstract
Transcranial magnetic stimulation (TMS) is a non-invasive brain stimulation technique able to modulate cortical excitability. This modulation may influence areas and networks responsible for specific cognitive processes, and the repetition of the induced temporary changes can produce long-lasting effects. TMS effectiveness may be enhanced when used in conjunction with cognitive training focused on specific cognitive functions. Playing video games can be an optimal cognitive training since it involves different cognitive components and high levels of engagement and motivation. The goal of this study is to assess the synergistic effects of TMS and video game training to enhance cognition, specifically, working memory and executive functions. We conducted a randomized 2 × 3 repeated measures (stimulation × time) study, randomly assigning 27 healthy volunteers to an active intermittent theta-burst stimulation or a sham stimulation group. Participants were assessed using a comprehensive neuropsychological battery before, immediately after, and 15 days after finishing the video game+TMS training. The training consisted of 10 sessions where participants played a 3D platform video game for 1.5 h. After each gaming session, TMS was applied over the right dorsolateral prefrontal cortex (DLPFC). All participants improved their video gaming performance, but we did not find a synergistic effect of stimulation and video game training. Neither had we found cognitive improvements related to the stimulation. We explored possible confounding variables such as age, gender, and early video gaming experience through linear regression. The early video gaming experience was related to improvements in working memory and inhibitory control. This result, although exploratory, highlights the influence of individual variables and previous experiences on brain plasticity.
Collapse
Affiliation(s)
| | - Raquel Viejo-Sobera
- Cognitive NeuroLab, Faculty of Health Sciences, Universitat Oberta de Catalunya (UOC), Barcelona, Spain
| | | | | |
Collapse
|
5
|
Orexin-1 receptor blockade differentially affects spatial and visual discrimination memory facilitation by intracranial self-stimulation. Neurobiol Learn Mem 2020; 169:107188. [PMID: 32061874 DOI: 10.1016/j.nlm.2020.107188] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2019] [Revised: 02/06/2020] [Accepted: 02/11/2020] [Indexed: 01/07/2023]
Abstract
Intracranial self-stimulation (ICSS) of the medial forebrain bundle is an effective treatment to facilitate memory. Performance in both explicit and implicit memory tasks has been improved by ICSS, and this treatment has even been capable of recovering loss of memory function due to lesions or old age. Several neurochemical systems have been studied in regard to their role in ICSS effects on memory, however the possible involvement of the orexinergic system in this facilitation has yet to be explored. The present study aims to examine the relationship between the OX1R and the facilitative effects of ICSS on two different types of memory tasks, both carried out in the Morris Water Maze: spatial and visual discrimination. Results show that the OX1R blockade, by intraventricular administration of SB-334867, partially negates the facilitating effect of ICSS on spatial memory, whereas it hinders ICSS facilitation of the discrimination task. However, ICSS treatment was capable of compensating for the severe detrimental effects of OX1R blockade on both memory paradigms. These results suggest different levels of involvement of the orexinergic system in the facilitation of memory by ICSS, depending on the memory task.
Collapse
|
6
|
Rewarding deep brain stimulation at the medial forebrain bundle favours avoidance conditioned response in a remote memory test, hinders extinction and increases neurogenesis. Behav Brain Res 2020; 378:112308. [PMID: 31629001 DOI: 10.1016/j.bbr.2019.112308] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Revised: 10/15/2019] [Accepted: 10/15/2019] [Indexed: 12/16/2022]
Abstract
Intracranial Self-Stimulation (ICSS) at the medial forebrain bundle consistently facilitates learning and memory in rats when administered post-training or when administered non-concurrent to training, but its scope regarding remote memory has not yet been studied. The present work aims to test whether the combination of these two forms of ICSS administration can cause a greater persistence of the facilitating effect on remote retention and affect neurogenesis in the dentate gyrus (DG) of the hippocampus. Rats were trained in active avoidance conditioning and tested in two retention sessions (10 and 90 days) and later extinction. Subjects received an ICSS session after each of the five avoidance acquisition sessions (post-training treatment) and half of them also received ten additional ICSS sessions during the rest period between retention tests (non-concurrent treatment). All the stimulated groups showed a higher performance in acquisition and retention sessions, but only the rats receiving both ICSS treatments showed greater resistance to extinction. Remarkably, at seven months, rats receiving the non-concurrent ICSS treatment had a greater number of DCX-positive cells in the DG as well as a higher amount of new-born cells within the granular layer compared to rats that did not receive this additional ICSS treatment. Our present findings significantly extend the temporal window of the facilitating effect of ICSS on active avoidance and demonstrate a neurogenic effect of rewarding medial forebrain bundle stimulation.
Collapse
|
7
|
García-Brito S, Morgado-Bernal I, Biosca-Simon N, Segura-Torres P. Intracranial self-stimulation also facilitates learning in a visual discrimination task in the Morris water maze in rats. Behav Brain Res 2017; 317:360-366. [DOI: 10.1016/j.bbr.2016.09.069] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Revised: 09/27/2016] [Accepted: 09/30/2016] [Indexed: 12/12/2022]
|
8
|
Kádár E, Vico-Varela E, Aldavert-Vera L, Huguet G, Morgado-Bernal I, Segura-Torres P. Increase in c-Fos and Arc protein in retrosplenial cortex after memory-improving lateral hypothalamic electrical stimulation treatment. Neurobiol Learn Mem 2016; 128:117-24. [DOI: 10.1016/j.nlm.2015.12.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Revised: 12/21/2015] [Accepted: 12/30/2015] [Indexed: 12/19/2022]
|
9
|
Kádár E, Ramoneda M, Aldavert-Vera L, Huguet G, Morgado-Bernal I, Segura-Torres P. Rewarding brain stimulation reverses the disruptive effect of amygdala damage on emotional learning. Behav Brain Res 2014; 274:43-52. [DOI: 10.1016/j.bbr.2014.07.050] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2014] [Revised: 07/24/2014] [Accepted: 07/28/2014] [Indexed: 12/11/2022]
|
10
|
Intracranial self-stimulation facilitates active-avoidance retention and induces expression of c-Fos and Nurr1 in rat brain memory systems. Behav Brain Res 2013; 250:46-57. [DOI: 10.1016/j.bbr.2013.04.025] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2012] [Revised: 04/15/2013] [Accepted: 04/19/2013] [Indexed: 01/05/2023]
|
11
|
Kadar E, Aldavert-Vera L, Huguet G, Costa-Miserachs D, Morgado-Bernal I, Segura-Torres P. Intracranial self-stimulation induces expression of learning and memory-related genes in rat amygdala. GENES BRAIN AND BEHAVIOR 2010; 10:69-77. [DOI: 10.1111/j.1601-183x.2010.00609.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
12
|
Hamani C, Dubiela FP, Soares JCK, Shin D, Bittencourt S, Covolan L, Carlen PL, Laxton AW, Hodaie M, Stone SSD, Ha Y, Hutchison WD, Lozano AM, Mello LE, Oliveira MGM. Anterior thalamus deep brain stimulation at high current impairs memory in rats. Exp Neurol 2010; 225:154-62. [PMID: 20558163 DOI: 10.1016/j.expneurol.2010.06.007] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2010] [Revised: 05/29/2010] [Accepted: 06/07/2010] [Indexed: 11/26/2022]
Abstract
Deep brain stimulation (DBS) of the anterior thalamic nucleus (AN), an important relay in the circuitry of memory, is currently being proposed as a treatment for epilepsy. Despite the encouraging results with the use of this therapy, potential benefits and adverse effects are yet to be determined. We show that AN stimulation at relatively high current disrupted the acquisition of contextual fear conditioning and impaired performance on a spatial alternating task in rats. This has not been observed at parameters generating a charge density that approximated the one used in clinical practice. At settings that impaired behavior, AN stimulation induced a functional depolarization block nearby the electrode, increased c-Fos expression in cerebral regions projecting to and receiving projections from the AN, and influenced hippocampal activity. This suggests that complex mechanisms might be involved in the effects of AN DBS, including a local target inactivation and the modulation of structures at a distance. Though translating data from animals to humans has to be considered with caution, our study underscores the need for carefully monitoring memory function while selecting stimulation parameters during the clinical evaluation of AN DBS.
Collapse
Affiliation(s)
- Clement Hamani
- Division of Neurosurgery, Toronto Western Hospital, Toronto, Ontario, Canada.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
13
|
Intracranial self-stimulation recovers learning and memory capacity in basolateral amygdala-damaged rats. Neurobiol Learn Mem 2010; 93:117-26. [DOI: 10.1016/j.nlm.2009.09.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2009] [Revised: 09/03/2009] [Accepted: 09/09/2009] [Indexed: 11/23/2022]
|
14
|
Intracranial self-stimulation to the lateral hypothalamus, a memory improving treatment, results in hippocampal changes in gene expression. Neuroscience 2009; 162:359-74. [DOI: 10.1016/j.neuroscience.2009.04.074] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2009] [Revised: 04/24/2009] [Accepted: 04/30/2009] [Indexed: 12/20/2022]
|
15
|
Ruiz-Medina J, Morgado-Bernal I, Redolar-Ripoll D, Aldavert-Vera L, Segura-Torres P. Intracranial self-stimulation facilitates a spatial learning and memory task in the Morris water maze. Neuroscience 2008; 154:424-30. [DOI: 10.1016/j.neuroscience.2008.03.059] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2008] [Revised: 03/13/2008] [Accepted: 03/17/2008] [Indexed: 10/22/2022]
|
16
|
Intracranial self-stimulation improves memory consolidation in rats with little training. Neurobiol Learn Mem 2008; 89:574-81. [DOI: 10.1016/j.nlm.2007.11.005] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2007] [Revised: 11/19/2007] [Accepted: 11/27/2007] [Indexed: 11/18/2022]
|
17
|
Soriano-Mas C, Redolar-Ripoll D, Guillazo-Blanch G, Morgado-Bernal I, Segura-Torres P. Intracranial self-stimulation after memory reactivation: Immediate and late effects. Brain Res Bull 2007; 74:51-7. [PMID: 17683789 DOI: 10.1016/j.brainresbull.2007.05.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2006] [Revised: 04/12/2007] [Accepted: 05/03/2007] [Indexed: 11/18/2022]
Abstract
To assess whether intracranial self-stimulation (SS) given after memory reactivation could improve memory retrieval, we tested the immediate (Experiment 1) and late (24 h; Experiment 2) effects of an SS treatment on the retrieval of a two-way active avoidance conditioning in Wistar rats. Memory was reactivated 24 h after training and the reminder (Rm) used consisted of a 3 s exposure to the conditioned stimulus (a tone) in the same context as in the original learning. SS treatment (2500 trains at 100% of each rat's optimal intensity) was administered immediately afterwards. No significant differences between SS-treated and control groups were observed when the retrieval was tested immediately after the SS treatment with or without memory reactivation. However, retrieval was improved when tested 24 h after SS treatment alone or after the reminder exposure alone. The greatest improvement in avoidance was observed when both treatments were given together, that is, when the SS treatment was administered immediately after memory reactivation. Moreover, there were no significant statistical interactions between the effect of SS treatment and the ones of memory reactivation in any of both experiments. The present results show that the effect of an immediate SS treatment can be added to the ones of memory reactivation causing a strong long-term facilitation of memory retrieval.
Collapse
Affiliation(s)
- Carles Soriano-Mas
- Unitat de Psicobiologia, Institut de Neurociències, Universitat Autònoma de Barcelona, Barcelona, Spain
| | | | | | | | | |
Collapse
|
18
|
Soriano-Mas C, Redolar-Ripoll D, Aldavert-Vera L, Morgado-Bernal I, Segura-Torres P. Post-training intracranial self-stimulation facilitates a hippocampus-dependent task. Behav Brain Res 2005; 160:141-7. [PMID: 15836909 DOI: 10.1016/j.bbr.2004.11.025] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2004] [Revised: 11/22/2004] [Accepted: 11/22/2004] [Indexed: 11/21/2022]
Abstract
Previous research has shown that post-training intracranial self-stimulation facilitates implicit or procedural memory. To know whether it can also facilitate explicit memory, post-training intracranial self-stimulation was given to Wistar rats immediately after every daily session of a delayed spatial alternation task that seems to depend on the integrity of the hippocampal memory system. We tested the effects of intracranial self-stimulation in three consecutive learning phases which tried to make the task progressively more difficult: 10 s delay (D10 phase), 30 s delay (D30 phase), and inverting the starting position of the animals to make their response more dependent on allocentric cues (INV phase). Every phase finished when each rat achieved a fixed learning criterion. Intracranial self-stimulation facilitated the flexible expression of the learned response (INV phase). That is, when the starting position was randomly inverted, only the rats that received intracranial self-stimulation maintained the performance level acquired in the previous training phases. Changing the starting position reduced the correct performance of the non-treated subjects, which need more training sessions to achieve the learning criterion and made less correct responses than treated rats. These findings show that post-training intracranial self-stimulation can facilitate hippocampus-dependent memories.
Collapse
Affiliation(s)
- Carles Soriano-Mas
- Unitat de Psicobiologia, Institut de Neurociències, Departament de Psicobiologia i de Metodologia de les Ciències de la Salut, Facultat de Psicologia, Edifici B., Universitat Autònoma de Barcelona, 08193 Bellaterra, Barcelona, Spain
| | | | | | | | | |
Collapse
|
19
|
Walling SG, Nutt DJ, Lalies MD, Harley CW. Orexin-A infusion in the locus ceruleus triggers norepinephrine (NE) release and NE-induced long-term potentiation in the dentate gyrus. J Neurosci 2004; 24:7421-6. [PMID: 15329388 PMCID: PMC6729640 DOI: 10.1523/jneurosci.1587-04.2004] [Citation(s) in RCA: 82] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2003] [Revised: 07/13/2004] [Accepted: 07/15/2004] [Indexed: 11/21/2022] Open
Abstract
The orexins (ORX-A/ORX-B) are neuroactive peptides known to have roles in feeding and sleep. Evidence of dense, excitatory projections of ORX-A neurons to the noradrenergic pontine nucleus, the locus ceruleus (LC), suggests ORX-A also participates in attention and memory. Activation of LC neurons by glutamate produces a beta-adrenergic receptor-mediated long-term potentiation (LTP) of the perforant path-evoked potential in the dentate gyrus, a target structure of the LC that has been implicated in memory. We asked whether ORX-A also activates norepinephrine (NE)-induced LTP by initiating NE release in the hippocampus. Here, we show that ORX-A infusion (0.25-25 fmol) into the LC produces a robust, beta-adrenergic receptor-dependent, long-lasting potentiation of the perforant path-evoked dentate gyrus population spike in the anesthetized rat. Pharmacological inactivation of the LC with an alpha2-adrenergic receptor agonist, before ORX-A infusion, prevents this potentiation. Analysis of NE concentrations in the hippocampus after ORX-A infusion into the LC reveals a transient, but robust, increase in NE release. Thus, this study demonstrates that the dense orexinergic projection to the LC promotes the induction of NE-LTP in the dentate gyrus. ORX-A modulation of LC activity may provide important support for the cognitive processes of attention and memory.
Collapse
Affiliation(s)
- Susan G Walling
- Department of Psychology, Memorial University of Newfoundland, St. John's, Newfoundland, Canada A1B 3X9
| | | | | | | |
Collapse
|
20
|
Redolar-Ripoll D, Soriano-Mas C, Guillazo-Blanch G, Aldavert-Vera L, Segura-Torres P, Morgado-Bernal I. Posttraining intracranial self-stimulation ameliorates the detrimental effects of parafascicular thalamic lesions on active avoidance in young and aged rats. Behav Neurosci 2003; 117:246-56. [PMID: 12708521 DOI: 10.1037/0735-7044.117.2.246] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
To evaluate whether intracranial self-stimulation (SS) ameliorates conditioning deficits induced by parafascicular nucleus (PF) damage in young and aged rats, the authors gave rats a daily session of 2-way active avoidance until a fixed criterion was achieved. Four experimental groups were established in both young and aged rats: SS treatment after every conditioning session (SS groups), pretraining PF lesions (lesion groups), PF lesions and SS treatment (L + SS groups), and controls. SS treatment not only canceled the detrimental effects of PF lesions, but also improved conditioning in lesioned rats (L + SS groups). This effect was more powerful in aged rats. SS treatment compensated for memory deficits generated by hypofunctionality of arousal systems such as that involving the PF.
Collapse
Affiliation(s)
- Diego Redolar-Ripoll
- Institut de Neurosiènces, Unitat de Psicobiologia, Universitat Autònoma de Barcelona, Bellaterra, Spain
| | | | | | | | | | | |
Collapse
|
21
|
Lee Kavanau J. REM and NREM sleep as natural accompaniments of the evolution of warm-bloodedness. Neurosci Biobehav Rev 2002; 26:889-906. [PMID: 12667495 DOI: 10.1016/s0149-7634(02)00088-x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Divergence of primitive sleep into REM and NREM states is thought to have occurred in the nocturnal Triassic ancestors of mammals as a natural accompaniment of the evolution of warm-bloodedness. As ambient temperatures during twilight portions of primitive sleep traversed these evolving ancestors' core temperature, mechanisms of thermoregulatory control that employ muscle contractions became superfluous. The resulting loss of need for such contractions during twilight sleep led to muscle atonia. With muscle tone absent, selection favored the persistence of the fast waves of nocturnal activity during twilight sleep. Stimulations by these waves reinforce motor circuits at the increasing temperatures of evolving warm-bloodedness without leading to sleep-disturbing muscle contractions. By these and related interlinked adaptations, twilight sleep evolved into REM sleep. The daytime period of sleep became NREM sleep. The evolution of NREM and REM sleep following this scenario has implications for sleep's maintenance processes for long-term memories. During NREM sleep, there is an unsynchronized, uncoordinated stimulation and reinforcement of individual distributed component circuits of consolidated memories by slow wave potentials, a process termed 'uncoordinated reinforcement'. The corresponding process during REM sleep is the coordinated stimulation and reinforcement of these circuits by fast wave potentials. This action temporally binds the individual component circuit outputs into fully formed memories, a process termed 'coordinated reinforcement'. Sequential uncoordinated and coordinated reinforcement, that is, NREM followed by REM sleep, emerges as the most effective mechanism of long-term memory maintenance in vertebrates. With the evolution of this two-stage mechanism of long-term memory maintenance, it became adaptive to partition sleep into several NREM-REM cycles, thereby achieving a more lengthy application of the cooperative sequential actions.
Collapse
Affiliation(s)
- J Lee Kavanau
- Department of Organismic Biology, Ecology and Evolution, University of California at Los Angeles (UCLA), 4 90095-1606, USA.
| |
Collapse
|