1
|
The Non-Linear Path from Gene Dysfunction to Genetic Disease: Lessons from the MICPCH Mouse Model. Cells 2022; 11:cells11071131. [PMID: 35406695 PMCID: PMC8997851 DOI: 10.3390/cells11071131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 03/09/2022] [Accepted: 03/24/2022] [Indexed: 11/17/2022] Open
Abstract
Most human disease manifests as a result of tissue pathology, due to an underlying disease process (pathogenesis), rather than the acute loss of specific molecular function(s). Successful therapeutic strategies thus may either target the correction of a specific molecular function or halt the disease process. For the vast majority of brain diseases, clear etiologic and pathogenic mechanisms are still elusive, impeding the discovery or design of effective disease-modifying drugs. The development of valid animal models and their proper characterization is thus critical for uncovering the molecular basis of the underlying pathobiological processes of brain disorders. MICPCH (microcephaly and pontocerebellar hypoplasia) is a monogenic condition that results from variants of an X-linked gene, CASK (calcium/calmodulin-dependent serine protein kinase). CASK variants are associated with a wide range of clinical presentations, from lethality and epileptic encephalopathies to intellectual disabilities, microcephaly, and autistic traits. We have examined CASK loss-of-function mutations in model organisms to simultaneously understand the pathogenesis of MICPCH and the molecular function/s of CASK. Our studies point to a highly complex relationship between the potential molecular function/s of CASK and the phenotypes observed in model organisms and humans. Here we discuss the implications of our observations from the pathogenesis of MICPCH as a cautionary narrative against oversimplifying molecular interpretations of data obtained from genetically modified animal models of human diseases.
Collapse
|
2
|
Paez Segala MG, Looger LL. Optogenetics. Mol Imaging 2021. [DOI: 10.1016/b978-0-12-816386-3.00092-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
|
3
|
Nazaré TE, Nepomuceno EG, Martins SAM, Butusov DN. A Note on the Reproducibility of Chaos Simulation. ENTROPY (BASEL, SWITZERLAND) 2020; 22:E953. [PMID: 33286722 PMCID: PMC7597239 DOI: 10.3390/e22090953] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 08/24/2020] [Accepted: 08/27/2020] [Indexed: 11/21/2022]
Abstract
An evergreen scientific feature is the ability for scientific works to be reproduced. Since chaotic systems are so hard to understand analytically, numerical simulations assume a key role in their investigation. Such simulations have been considered as reproducible in many works. However, few studies have focused on the effects of the finite precision of computers on the simulation reproducibility of chaotic systems; moreover, code sharing and details on how to reproduce simulation results are not present in many investigations. In this work, a case study of reproducibility is presented in the simulation of a chaotic jerk circuit, using the software LTspice. We also employ the OSF platform to share the project associated with this paper. Tests performed with LTspice XVII on four different computers show the difficulties of simulation reproducibility by this software. We compare these results with experimental data using a normalised root mean square error in order to identify the computer with the highest prediction horizon. We also calculate the entropy of the signals to check differences among computer simulations and the practical experiment. The methodology developed is efficient in identifying the computer with better performance, which allows applying it to other cases in the literature. This investigation is fully described and available on the OSF platform.
Collapse
Affiliation(s)
- Thalita E. Nazaré
- Control and Modelling Group (GCOM), Department of Electrical Engineering, Federal University of São João del-Rei, São João del-Rei, MG 36307-352, Brazil; (T.E.N.); (S.A.M.M.)
| | - Erivelton G. Nepomuceno
- Control and Modelling Group (GCOM), Department of Electrical Engineering, Federal University of São João del-Rei, São João del-Rei, MG 36307-352, Brazil; (T.E.N.); (S.A.M.M.)
| | - Samir A. M. Martins
- Control and Modelling Group (GCOM), Department of Electrical Engineering, Federal University of São João del-Rei, São João del-Rei, MG 36307-352, Brazil; (T.E.N.); (S.A.M.M.)
| | - Denis N. Butusov
- Youth Research Institute, Saint-Petersburg Electrotechnical University “LETI”, 197376 Saint Petersburg, Russia;
| |
Collapse
|
4
|
Octeau JC, Gangwani MR, Allam SL, Tran D, Huang S, Hoang-Trong TM, Golshani P, Rumbell TH, Kozloski JR, Khakh BS. Transient, Consequential Increases in Extracellular Potassium Ions Accompany Channelrhodopsin2 Excitation. Cell Rep 2020; 27:2249-2261.e7. [PMID: 31116972 PMCID: PMC6582980 DOI: 10.1016/j.celrep.2019.04.078] [Citation(s) in RCA: 57] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Revised: 03/04/2019] [Accepted: 04/17/2019] [Indexed: 12/13/2022] Open
Abstract
Channelrhodopsin2 (ChR2) optogenetic excitation is widely used to study neurons, astrocytes, and circuits. Using complementary approaches in situ and in vivo, we found that ChR2 stimulation leads to significant transient elevation of extracellular potassium ions by ~5 mM. Such elevations were detected in ChR2-expressing mice, following local in vivo expression of ChR2(H134R) with adeno-associated viruses (AAVs), in different brain areas and when ChR2 was expressed in neurons or astrocytes. In particular, ChR2-mediated excitation of striatal astrocytes was sufficient to increase medium spiny neuron (MSN) excitability and immediate early gene expression. The effects on MSN excitability were recapitulated in silico with a computational MSN model and detected in vivo as increased action potential firing in awake, behaving mice. We show that transient, physiologically consequential increases in extracellular potassium ions accompany ChR2 optogenetic excitation. This coincidental effect may be important to consider during astrocyte studies employing ChR2 to interrogate neural circuits and animal behavior. Using multiple approaches, Octeau et al. discover that optogenetic excitation of ChR2-expressing cells leads to significant transient extracellular potassium ion elevations that increase neuronal excitability and immediate early gene expression in neurons following in vivo stimulation.
Collapse
Affiliation(s)
- J Christopher Octeau
- Department of Physiology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095-1751, USA
| | - Mohitkumar R Gangwani
- Department of Physiology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095-1751, USA
| | - Sushmita L Allam
- IBM T.J. Watson Research Center, P.O. Box 218, 1101 Kitchawan Road, Yorktown Heights, NY 10598, USA
| | - Duy Tran
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095-1751, USA
| | - Shuhan Huang
- Department of Physiology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095-1751, USA
| | - Tuan M Hoang-Trong
- IBM T.J. Watson Research Center, P.O. Box 218, 1101 Kitchawan Road, Yorktown Heights, NY 10598, USA
| | - Peyman Golshani
- Department of Neurology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095-1751, USA; Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095-1751, USA; Intellectual and Developmental Disabilities Research Center, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095-1751, USA; Center for Neurobehavioral Genetics, Semel Institute for Neuroscience and Human Behavior, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095-1751, USA
| | - Timothy H Rumbell
- IBM T.J. Watson Research Center, P.O. Box 218, 1101 Kitchawan Road, Yorktown Heights, NY 10598, USA
| | - James R Kozloski
- IBM T.J. Watson Research Center, P.O. Box 218, 1101 Kitchawan Road, Yorktown Heights, NY 10598, USA
| | - Baljit S Khakh
- Department of Physiology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095-1751, USA; Department of Neurobiology, David Geffen School of Medicine, University of California, Los Angeles, Los Angeles, CA 90095-1751, USA.
| |
Collapse
|
5
|
Yu X, Nagai J, Khakh BS. Improved tools to study astrocytes. Nat Rev Neurosci 2020; 21:121-138. [DOI: 10.1038/s41583-020-0264-8] [Citation(s) in RCA: 112] [Impact Index Per Article: 28.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/09/2020] [Indexed: 12/21/2022]
|
6
|
Hippocampal Global Remapping Can Occur without Input from the Medial Entorhinal Cortex. Cell Rep 2019; 22:3152-3159. [PMID: 29562172 PMCID: PMC5929481 DOI: 10.1016/j.celrep.2018.02.082] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2017] [Revised: 12/26/2017] [Accepted: 02/21/2018] [Indexed: 12/11/2022] Open
Abstract
The high storage capacity of the episodic memory system relies on distinct representations for events that are separated in time and space. The spatial component of these computations includes the formation of independent maps by hippocampal place cells across environments, referred to as global re-mapping. Such remapping is thought to emerge by the switching of input patterns from specialized spatially selective cells in medial entorhinal cortex (mEC), such as grid and border cells. Although it has been shown that acute manipulations of mEC firing patterns are sufficient for inducing hippocampal remapping, it remains unknown whether specialized spatial mEC inputs are necessary for the reorganization of hippocampal spatial representations. Here, we examined remapping in rats without mEC input to the hippocampus and found that highly distinct spatial maps emerged rapidly in every individual rat. Our data suggest that hippocampal spatial computations do not depend on inputs from specialized cell types in mEC.
Collapse
|
7
|
Bayless DW, Yang T, Mason MM, Susanto AAT, Lobdell A, Shah NM. Limbic Neurons Shape Sex Recognition and Social Behavior in Sexually Naive Males. Cell 2019; 176:1190-1205.e20. [PMID: 30712868 PMCID: PMC6453703 DOI: 10.1016/j.cell.2018.12.041] [Citation(s) in RCA: 70] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Revised: 11/13/2018] [Accepted: 12/21/2018] [Indexed: 12/18/2022]
Abstract
Sexually naive animals have to distinguish between the sexes because they show species-typical interactions with males and females without meaningful prior experience. However, central neural pathways in naive mammals that recognize sex of other individuals remain poorly characterized. We examined the role of the principal component of the bed nucleus of stria terminalis (BNSTpr), a limbic center, in social interactions in mice. We find that activity of aromatase-expressing BNSTpr (AB) neurons appears to encode sex of other animals and subsequent displays of mating in sexually naive males. Silencing these neurons in males eliminates preference for female pheromones and abrogates mating success, whereas activating them even transiently promotes male-male mating. Surprisingly, female AB neurons do not appear to control sex recognition, mating, or maternal aggression. In summary, AB neurons represent sex of other animals and govern ensuing social behaviors in sexually naive males.
Collapse
Affiliation(s)
- Daniel W Bayless
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA 94305, USA
| | - Taehong Yang
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA 94305, USA
| | - Matthew M Mason
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA 94305, USA
| | - Albert A T Susanto
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA 94305, USA
| | - Alexandra Lobdell
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA 94305, USA
| | - Nirao M Shah
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA 94305, USA; Department of Neurobiology, Stanford University, Stanford, CA 94305, USA.
| |
Collapse
|
8
|
Ferbinteanu J. Memory systems 2018 - Towards a new paradigm. Neurobiol Learn Mem 2019; 157:61-78. [PMID: 30439565 PMCID: PMC6389412 DOI: 10.1016/j.nlm.2018.11.005] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2018] [Revised: 10/29/2018] [Accepted: 11/10/2018] [Indexed: 12/26/2022]
Abstract
The multiple memory systems theory (MMS) postulates that the brain stores information based on the independent and parallel activity of a number of modules, each with distinct properties, dynamics, and neural basis. Much of the evidence for this theory comes from dissociation studies indicating that damage to restricted brain areas cause selective types of memory deficits. MMS has been the prevalent paradigm in memory research for more than thirty years, even as it has been adjusted several times to accommodate new data. However, recent empirical results indicating that the memory systems are not always dissociable constitute a challenge to fundamental tenets of the current theory because they suggest that representations formed by individual memory systems can contribute to more than one type of memory-driven behavioral strategy. This problem can be addressed by applying a dynamic network perspective to memory architecture. According to this view, memory networks can reconfigure or transiently couple in response to environmental demands. Within this context, the neural network underlying a specific memory system can act as an independent unit or as an integrated component of a higher order meta-network. This dynamic network model proposes a way in which empirical evidence that challenges the idea of distinct memory systems can be incorporated within a modular memory architecture. The model also provides a framework to account for the complex interactions among memory systems demonstrated at the behavioral level. Advances in the study of dynamic networks can generate new ideas to experimentally manipulate and control memory in basic or clinical research.
Collapse
Affiliation(s)
- J Ferbinteanu
- Dept. of Physiology and Pharmacology, Dept. of Neurology, SUNY Downstate Medical Center, 450 Clarkson Ave, Box 31, Brooklyn, NY 11203, USA.
| |
Collapse
|
9
|
Devan BD, Berger K, McDonald RJ. The Emergent Engram: A Historical Legacy and Contemporary Discovery. Front Behav Neurosci 2018; 12:168. [PMID: 30131682 PMCID: PMC6090515 DOI: 10.3389/fnbeh.2018.00168] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Accepted: 07/16/2018] [Indexed: 01/10/2023] Open
Affiliation(s)
- Bryan D Devan
- Laboratory of Comparative Neuropsychology, Psychology Department, Towson University, Towson, MD, United States
| | - Kyle Berger
- Laboratory of Comparative Neuropsychology, Psychology Department, Towson University, Towson, MD, United States
| | - Robert J McDonald
- Canadian Center for Behavioural Neuroscience, University of Lethbridge, Lethbridge, AB, Canada
| |
Collapse
|
10
|
A neural network for intermale aggression to establish social hierarchy. Nat Neurosci 2018; 21:834-842. [DOI: 10.1038/s41593-018-0153-x] [Citation(s) in RCA: 66] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Accepted: 04/05/2018] [Indexed: 11/08/2022]
|
11
|
Yu X, Franks NP, Wisden W. Sleep and Sedative States Induced by Targeting the Histamine and Noradrenergic Systems. Front Neural Circuits 2018; 12:4. [PMID: 29434539 PMCID: PMC5790777 DOI: 10.3389/fncir.2018.00004] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Accepted: 01/11/2018] [Indexed: 01/07/2023] Open
Abstract
Sedatives target just a handful of receptors and ion channels. But we have no satisfying explanation for how activating these receptors produces sedation. In particular, do sedatives act at restricted brain locations and circuitries or more widely? Two prominent sedative drugs in clinical use are zolpidem, a GABAA receptor positive allosteric modulator, and dexmedetomidine (DEX), a selective α2 adrenergic receptor agonist. By targeting hypothalamic neuromodulatory systems both drugs induce a sleep-like state, but in different ways: zolpidem primarily reduces the latency to NREM sleep, and is a controlled substance taken by many people to help them sleep; DEX produces prominent slow wave activity in the electroencephalogram (EEG) resembling stage 2 NREM sleep, but with complications of hypothermia and lowered blood pressure—it is used for long term sedation in hospital intensive care units—under DEX-induced sedation patients are arousable and responsive, and this drug reduces the risk of delirium. DEX, and another α2 adrenergic agonist xylazine, are also widely used in veterinary clinics to sedate animals. Here we review how these two different classes of sedatives, zolpidem and dexmedetomideine, can selectively interact with some nodal points of the circuitry that promote wakefulness allowing the transition to NREM sleep. Zolpidem enhances GABAergic transmission onto histamine neurons in the hypothalamic tuberomammillary nucleus (TMN) to hasten the transition to NREM sleep, and DEX interacts with neurons in the preoptic hypothalamic area that induce sleep and body cooling. This knowledge may aid the design of more precise acting sedatives, and at the same time, reveal more about the natural sleep-wake circuitry.
Collapse
Affiliation(s)
- Xiao Yu
- Department of Life Sciences, Imperial College London, London, United Kingdom
| | - Nicholas P Franks
- Department of Life Sciences, Imperial College London, London, United Kingdom.,Centre for Neurotechnology, Imperial College London, London, United Kingdom.,UK Dementia Research Institute, Imperial College London, London, United Kingdom
| | - William Wisden
- Department of Life Sciences, Imperial College London, London, United Kingdom.,Centre for Neurotechnology, Imperial College London, London, United Kingdom.,UK Dementia Research Institute, Imperial College London, London, United Kingdom
| |
Collapse
|
12
|
Abstract
The motor cortex is a large frontal structure in the cerebral cortex of eutherian mammals. A vast array of evidence implicates the motor cortex in the volitional control of motor output, but how does the motor cortex exert this 'control'? Historically, ideas regarding motor cortex function have been shaped by the discovery of cortical 'motor maps' - that is, ordered representations of stimulation-evoked movements in anaesthetized animals. Volitional control, however, entails the initiation of movements and the ability to suppress undesired movements. In this article, we highlight classic and recent findings that emphasize that motor cortex neurons have a role in both processes.
Collapse
|
13
|
Xu S, Das G, Hueske E, Tonegawa S. Dorsal Raphe Serotonergic Neurons Control Intertemporal Choice under Trade-off. Curr Biol 2017; 27:3111-3119.e3. [PMID: 28988863 PMCID: PMC5691357 DOI: 10.1016/j.cub.2017.09.008] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Revised: 08/11/2017] [Accepted: 09/06/2017] [Indexed: 11/28/2022]
Abstract
Appropriate choice about delayed reward is fundamental to the survival of animals. Although animals tend to prefer immediate reward, delaying gratification is often advantageous. The dorsal raphe (DR) serotonergic neurons have long been implicated in the processing of delayed reward, but it has been unclear whether or when their activity causally directs choice. Here, we transiently augmented or reduced the activity of DR serotonergic neurons, while mice decided between differently delayed rewards as they performed a novel odor-guided intertemporal choice task. We found that these manipulations, precisely targeted at the decision point, were sufficient to bidirectionally influence impulsive choice. The manipulation specifically affected choices with more difficult trade-off. Similar effects were observed when we manipulated the serotonergic projections to the nucleus accumbens (NAc). We propose that DR serotonergic neurons preempt reward delays at the decision point and play a critical role in suppressing impulsive choice by regulating decision trade-off.
Collapse
Affiliation(s)
- Sangyu Xu
- RIKEN-MIT Center for Neural Circuit Genetics at the Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Agency for Science, Technology and Research, Singapore 138632, Singapore.
| | - Gishnu Das
- RIKEN-MIT Center for Neural Circuit Genetics at the Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Emily Hueske
- RIKEN-MIT Center for Neural Circuit Genetics at the Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Susumu Tonegawa
- RIKEN-MIT Center for Neural Circuit Genetics at the Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Howard Hughes Medical Institute, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; Brain Science Institute, RIKEN, Wako, Saitama 351-0198, Japan.
| |
Collapse
|
14
|
Eriksson D. Estimating Neural Background Input with Controlled and Fast Perturbations: A Bandwidth Comparison between Inhibitory Opsins and Neural Circuits. Front Neural Circuits 2016; 10:58. [PMID: 27574506 PMCID: PMC4983554 DOI: 10.3389/fncir.2016.00058] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2016] [Accepted: 07/25/2016] [Indexed: 11/13/2022] Open
Abstract
To test the importance of a certain cell type or brain area it is common to make a "lack of function" experiment in which the neuronal population of interest is inhibited. Here we review physiological and methodological constraints for making controlled perturbations using the corticothalamic circuit as an example. The brain with its many types of cells and rich interconnectivity offers many paths through which a perturbation can spread within a short time. To understand the side effects of the perturbation one should record from those paths. We find that ephaptic effects, gap-junctions, and fast chemical synapses are so fast that they can react to the perturbation during the few milliseconds it takes for an opsin to change the membrane potential. The slow chemical synapses, astrocytes, extracellular ions and vascular signals, will continue to give their physiological input for around 20 ms before they also react to the perturbation. Although we show that some pathways can react within milliseconds the strength/speed reported in this review should be seen as an upper bound since we have omitted how polysynaptic signals are attenuated. Thus the number of additional recordings that has to be made to control for the perturbation side effects is expected to be fewer than proposed here. To summarize, the reviewed literature not only suggests that it is possible to make controlled "lack of function" experiments, but, it also suggests that such a "lack of function" experiment can be used to measure the context of local neural computations.
Collapse
Affiliation(s)
- David Eriksson
- Center for Neuroscience, Albert Ludwig University of FreiburgFreiburg, Germany; BrainLinks-BrainTools, Albert Ludwig University of FreiburgFreiburg, Germany
| |
Collapse
|
15
|
Abstract
Scientists, public servants, and patient advocates alike increasingly question the validity of published scientific results, endangering the public’s acceptance of science. Here, I argue that emerging flaws in the integrity of the peer review system are largely responsible. Distortions in peer review are driven by economic forces and enabled by a lack of accountability of journals, editors, and authors. One approach to restoring trust in the validity of published results may be to establish basic rules that render peer review more transparent, such as publishing the reviews (a practice already embraced by some journals) and monitoring not only the track records of authors but also of editors and journals. In this Perspective, Thomas C. Südhof describes some of the current challenges to the peer review system that have endangered public acceptance of science and discusses possible avenues to addressing these challenges.
Collapse
Affiliation(s)
- Thomas C. Südhof
- Department of Molecular and Cellular Physiology and Howard Hughes Medical Institute, Stanford University Medical School, Stanford, California, United States of America
- * E-mail:
| |
Collapse
|
16
|
Ferbinteanu J. Contributions of Hippocampus and Striatum to Memory-Guided Behavior Depend on Past Experience. J Neurosci 2016; 36:6459-70. [PMID: 27307234 PMCID: PMC5015782 DOI: 10.1523/jneurosci.0840-16.2016] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2016] [Revised: 05/03/2016] [Accepted: 05/07/2016] [Indexed: 11/21/2022] Open
Abstract
UNLABELLED The hippocampal and striatal memory systems are thought to operate independently and in parallel in supporting cognitive memory and habits, respectively. Much of the evidence for this principle comes from double dissociation data, in which damage to brain structure A causes deficits in Task 1 but not Task 2, whereas damage to structure B produces the reverse pattern of effects. Typically, animals are explicitly trained in one task. Here, we investigated whether this principle continues to hold when animals concurrently learn two types of tasks. Rats were trained on a plus maze in either a spatial navigation or a cue-response task (sequential training), whereas a third set of rats acquired both (concurrent training). Subsequently, the rats underwent either sham surgery or neurotoxic lesions of the hippocampus (HPC), medial dorsal striatum (DSM), or lateral dorsal striatum (DSL), followed by retention testing. Finally, rats in the sequential training condition also acquired the novel "other" task. When rats learned one task, HPC and DSL selectively supported spatial navigation and cue response, respectively. However, when rats learned both tasks, HPC and DSL additionally supported the behavior incongruent with the processing style of the corresponding memory system. Thus, in certain conditions, the hippocampal and striatal memory systems can operate cooperatively and in synergism. DSM significantly contributed to performance regardless of task or training procedure. Experience with the cue-response task facilitated subsequent spatial learning, whereas experience with spatial navigation delayed both concurrent and subsequent response learning. These findings suggest that there are multiple operational principles that govern memory networks. SIGNIFICANCE STATEMENT Currently, we distinguish among several types of memories, each supported by a distinct neural circuit. The memory systems are thought to operate independently and in parallel. Here, we demonstrate that the hippocampus and the dorsal striatum memory systems operate independently and in parallel when rats learn one type of task at a time, but interact cooperatively and in synergism when rats concurrently learn two types of tasks. Furthermore, new learning is modulated by past experiences. These results can be explained by a model in which independent and parallel information processing that occurs in the separate memory-related neural circuits is supplemented by information transfer between the memory systems at the level of the cortex.
Collapse
Affiliation(s)
- Janina Ferbinteanu
- Departments of Physiology and Pharmacology and Neurology, State University of New York Downstate Medical Center, Brooklyn, New York 11203
| |
Collapse
|