1
|
Farkhondeh Tale Navi F, Heysieattalab S, Raoufy MR, Sabaghypour S, Nazari M, Nazari MA. Adaptive closed-loop modulation of cortical theta oscillations: Insights into the neural dynamics of navigational decision-making. Brain Stimul 2024; 17:1101-1118. [PMID: 39277130 DOI: 10.1016/j.brs.2024.09.005] [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: 10/21/2023] [Revised: 08/04/2024] [Accepted: 09/10/2024] [Indexed: 09/17/2024] Open
Abstract
Navigational decision-making tasks, such as spatial working memory (SWM), rely highly on information integration from several cortical and sub-cortical regions. Performance in SWM tasks is associated with theta rhythm, including low-frequency oscillations related to movement and memory. The interaction of the ventral hippocampus (vHPC) and medial prefrontal cortex (mPFC), reflected in theta synchrony, is essential in various steps of information processing during SWM. We used a closed-loop neurofeedback (CLNF) system to upregulate theta power in the mPFC and investigate its effects on circuit dynamics and behavior in animal models. Specifically, we hypothesized that enhancing the power of the theta rhythm in the mPFC might improve SWM performance. Animals were divided into three groups: closed-loop (CL), random-loop (RL), and OFF (without stimulation). We recorded local field potential (LFP) in the mPFC while electrical reward stimulation contingent on cortical theta activity was delivered to the lateral hypothalamus (LH), which is considered one of the central reward-associated regions. We also recorded LFP in the vHPC to evaluate the related subcortical neural changes. Results revealed a sustained increase in the theta power in both mPFC and vHPC for the CL group. Our analysis also revealed an increase in mPFC-vHPC synchronization in the theta range over the stimulation sessions in the CL group, as measured by coherence and cross-correlation in the theta frequency band. The reinforcement of this circuit improved spatial decision-making performance in the subsequent behavioral results. Our findings provide direct evidence of the relationship between specific theta upregulation and SWM performance and suggest that theta oscillations are integral to cognitive processes. Overall, this study highlights the potential of adaptive CLNF systems in investigating neural dynamics in various brain circuits.
Collapse
Affiliation(s)
- Farhad Farkhondeh Tale Navi
- Department of Cognitive Neuroscience, Faculty of Education and Psychology, University of Tabriz, Tabriz, Iran
| | - Soomaayeh Heysieattalab
- Department of Cognitive Neuroscience, Faculty of Education and Psychology, University of Tabriz, Tabriz, Iran
| | - Mohammad Reza Raoufy
- Department of Physiology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran.
| | - Saied Sabaghypour
- Department of Cognitive Neuroscience, Faculty of Education and Psychology, University of Tabriz, Tabriz, Iran
| | - Milad Nazari
- Department of Molecular Biology and Genetics, Aarhus University, Denmark
| | - Mohammad Ali Nazari
- Department of Cognitive Neuroscience, Faculty of Education and Psychology, University of Tabriz, Tabriz, Iran; Department of Neuroscience, Faculty of Advanced Technologies in Medicine, Iran University of Medical Sciences, Tehran, Iran.
| |
Collapse
|
2
|
Young RA, Shin JD, Guo Z, Jadhav SP. Hippocampal-prefrontal communication subspaces align with behavioral and network patterns in a spatial memory task. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.07.08.601617. [PMID: 39026752 PMCID: PMC11257456 DOI: 10.1101/2024.07.08.601617] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/20/2024]
Abstract
Rhythmic network states have been theorized to facilitate communication between brain regions, but how these oscillations influence communication subspaces, i.e, the low-dimensional neural activity patterns that mediate inter-regional communication, and in turn how subspaces impact behavior remains unclear. Using a spatial memory task in rats, we simultaneously recorded ensembles from hippocampal CA1 and the prefrontal cortex (PFC) to address this question. We found that task behaviors best aligned with low-dimensional, shared subspaces between these regions, rather than local activity in either region. Critically, both network oscillations and speed modulated the structure and performance of this communication subspace. Contrary to expectations, theta coherence did not better predict CA1-PFC shared activity, while theta power played a more significant role. To understand the communication space, we visualized shared CA1-PFC communication geometry using manifold techniques and found ring-like structures. We hypothesize that these shared activity manifolds are utilized to mediate the task behavior. These findings suggest that memory-guided behaviors are driven by shared CA1-PFC interactions that are dynamically modulated by oscillatory states, offering a novel perspective on the interplay between rhythms and behaviorally relevant neural communication.
Collapse
|
3
|
Miles JT, Mullins GL, Mizumori SJY. Flexible decision-making is related to strategy learning, vicarious trial and error, and medial prefrontal rhythms during spatial set-shifting. Learn Mem 2024; 31:a053911. [PMID: 39038921 PMCID: PMC11369635 DOI: 10.1101/lm.053911.123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Accepted: 05/14/2024] [Indexed: 07/24/2024]
Abstract
Flexible decision-making requires a balance between exploring features of an environment and exploiting prior knowledge. Behavioral flexibility is typically measured by how long it takes subjects to consistently make accurate choices after reward contingencies switch or task rules change. This measure, however, only allows for tracking flexibility across multiple trials, and does not assess the degree of flexibility. Plus, although increases in decision-making accuracy are strong indicators of learning, other decision-making behaviors have also been suggested as markers of flexibility, such as the on-the-fly decision reversals known as vicarious trial and error (VTE) or switches to a different, but incorrect, strategy. We sought to relate flexibility, learning, and neural activity by comparing choice history-derived evaluation of strategy use with changes in decision-making accuracy and VTE behavior while recording from the medial prefrontal cortex (mPFC) in rats. Using a set-shifting task that required rats to repeatedly switch between spatial decision-making strategies, we show that a previously developed strategy likelihood estimation procedure could identify putative learning points based on decision history. We confirm the efficacy of learning point estimation by showing increases in decision-making accuracy aligned to the learning point. Additionally, we show increases in the rate of VTE behavior surrounding identified learning points. By calculating changes in strategy likelihoods across trials, we tracked flexibility on a trial-by-trial basis and show that flexibility scores also increased around learning points. Further, we demonstrate that VTE behaviors could be separated into indecisive and deliberative subtypes depending on whether they occurred during periods of high or low flexibility and whether they led to correct or incorrect choice outcomes. Field potential recordings from the mPFC during decisions exhibited increased beta band activity on trials with VTE compared to non-VTE trials, as well as increased gamma during periods when learned strategies could be exploited compared to prelearning, exploratory periods. This study demonstrates that increased behavioral flexibility and VTE rates are often aligned to task learning. These relationships can break down, however, suggesting that VTE is not always an indicator of deliberative decision-making. Additionally, we further implicate the mPFC in decision-making and learning by showing increased beta-based activity on VTE trials and increased gamma after learning.
Collapse
Affiliation(s)
- Jesse T Miles
- Neuroscience Graduate Program, University of Washington, Seattle, Washington 98195, USA
- Psychology Department, University of Washington, Seattle, Washington 98195, USA
| | - Ginger L Mullins
- Psychology Department, University of Washington, Seattle, Washington 98195, USA
| | - Sheri J Y Mizumori
- Neuroscience Graduate Program, University of Washington, Seattle, Washington 98195, USA
- Psychology Department, University of Washington, Seattle, Washington 98195, USA
| |
Collapse
|
4
|
Zhang T, Rosenberg M, Jing Z, Perona P, Meister M. Endotaxis: A neuromorphic algorithm for mapping, goal-learning, navigation, and patrolling. eLife 2024; 12:RP84141. [PMID: 38420996 PMCID: PMC10911395 DOI: 10.7554/elife.84141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/02/2024] Open
Abstract
An animal entering a new environment typically faces three challenges: explore the space for resources, memorize their locations, and navigate towards those targets as needed. Here we propose a neural algorithm that can solve all these problems and operates reliably in diverse and complex environments. At its core, the mechanism makes use of a behavioral module common to all motile animals, namely the ability to follow an odor to its source. We show how the brain can learn to generate internal "virtual odors" that guide the animal to any location of interest. This endotaxis algorithm can be implemented with a simple 3-layer neural circuit using only biologically realistic structures and learning rules. Several neural components of this scheme are found in brains from insects to humans. Nature may have evolved a general mechanism for search and navigation on the ancient backbone of chemotaxis.
Collapse
Affiliation(s)
- Tony Zhang
- Division of Biology and Biological Engineering, California Institute of TechnologyPasadenaUnited States
| | - Matthew Rosenberg
- Division of Biology and Biological Engineering, California Institute of TechnologyPasadenaUnited States
- Center for the Physics of Biological Function, Princeton UniversityPrincetonUnited States
| | - Zeyu Jing
- Division of Biology and Biological Engineering, California Institute of TechnologyPasadenaUnited States
| | - Pietro Perona
- Division of Engineering and Applied Science, California Institute of TechnologyPasadenaUnited States
| | - Markus Meister
- Division of Biology and Biological Engineering, California Institute of TechnologyPasadenaUnited States
| |
Collapse
|
5
|
Maselli A, Gordon J, Eluchans M, Lancia GL, Thiery T, Moretti R, Cisek P, Pezzulo G. Beyond simple laboratory studies: Developing sophisticated models to study rich behavior. Phys Life Rev 2023; 46:220-244. [PMID: 37499620 DOI: 10.1016/j.plrev.2023.07.006] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Accepted: 07/06/2023] [Indexed: 07/29/2023]
Abstract
Psychology and neuroscience are concerned with the study of behavior, of internal cognitive processes, and their neural foundations. However, most laboratory studies use constrained experimental settings that greatly limit the range of behaviors that can be expressed. While focusing on restricted settings ensures methodological control, it risks impoverishing the object of study: by restricting behavior, we might miss key aspects of cognitive and neural functions. In this article, we argue that psychology and neuroscience should increasingly adopt innovative experimental designs, measurement methods, analysis techniques and sophisticated computational models to probe rich, ecologically valid forms of behavior, including social behavior. We discuss the challenges of studying rich forms of behavior as well as the novel opportunities offered by state-of-the-art methodologies and new sensing technologies, and we highlight the importance of developing sophisticated formal models. We exemplify our arguments by reviewing some recent streams of research in psychology, neuroscience and other fields (e.g., sports analytics, ethology and robotics) that have addressed rich forms of behavior in a model-based manner. We hope that these "success cases" will encourage psychologists and neuroscientists to extend their toolbox of techniques with sophisticated behavioral models - and to use them to study rich forms of behavior as well as the cognitive and neural processes that they engage.
Collapse
Affiliation(s)
- Antonella Maselli
- Institute of Cognitive Sciences and Technologies, National Research Council, Rome, Italy
| | - Jeremy Gordon
- University of California, Berkeley, Berkeley, CA, 94704, United States
| | - Mattia Eluchans
- Institute of Cognitive Sciences and Technologies, National Research Council, Rome, Italy; University of Rome "La Sapienza", Rome, Italy
| | - Gian Luca Lancia
- Institute of Cognitive Sciences and Technologies, National Research Council, Rome, Italy; University of Rome "La Sapienza", Rome, Italy
| | - Thomas Thiery
- Department of Psychology, University of Montréal, Montréal, Québec, Canada
| | - Riccardo Moretti
- Institute of Cognitive Sciences and Technologies, National Research Council, Rome, Italy; University of Rome "La Sapienza", Rome, Italy
| | - Paul Cisek
- Department of Neuroscience, University of Montréal, Montréal, Québec, Canada
| | - Giovanni Pezzulo
- Institute of Cognitive Sciences and Technologies, National Research Council, Rome, Italy.
| |
Collapse
|
6
|
Lancia GL, Eluchans M, D’Alessandro M, Spiers HJ, Pezzulo G. Humans account for cognitive costs when finding shortcuts: An information-theoretic analysis of navigation. PLoS Comput Biol 2023; 19:e1010829. [PMID: 36608145 PMCID: PMC9851521 DOI: 10.1371/journal.pcbi.1010829] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Revised: 01/19/2023] [Accepted: 12/19/2022] [Indexed: 01/09/2023] Open
Abstract
When faced with navigating back somewhere we have been before we might either retrace our steps or seek a shorter path. Both choices have costs. Here, we ask whether it is possible to characterize formally the choice of navigational plans as a bounded rational process that trades off the quality of the plan (e.g., its length) and the cognitive cost required to find and implement it. We analyze the navigation strategies of two groups of people that are firstly trained to follow a "default policy" taking a route in a virtual maze and then asked to navigate to various known goal destinations, either in the way they want ("Go To Goal") or by taking novel shortcuts ("Take Shortcut"). We address these wayfinding problems using InfoRL: an information-theoretic approach that formalizes the cognitive cost of devising a navigational plan, as the informational cost to deviate from a well-learned route (the "default policy"). In InfoRL, optimality refers to finding the best trade-off between route length and the amount of control information required to find it. We report five main findings. First, the navigational strategies automatically identified by InfoRL correspond closely to different routes (optimal or suboptimal) in the virtual reality map, which were annotated by hand in previous research. Second, people deliberate more in places where the value of investing cognitive resources (i.e., relevant goal information) is greater. Third, compared to the group of people who receive the "Go To Goal" instruction, those who receive the "Take Shortcut" instruction find shorter but less optimal solutions, reflecting the intrinsic difficulty of finding optimal shortcuts. Fourth, those who receive the "Go To Goal" instruction modulate flexibly their cognitive resources, depending on the benefits of finding the shortcut. Finally, we found a surprising amount of variability in the choice of navigational strategies and resource investment across participants. Taken together, these results illustrate the benefits of using InfoRL to address navigational planning problems from a bounded rational perspective.
Collapse
Affiliation(s)
- Gian Luca Lancia
- Institute of Cognitive Sciences and Technologies, National Research Council, Rome, Italy
- University of Rome “La Sapienza”, Rome, Italy
| | - Mattia Eluchans
- Institute of Cognitive Sciences and Technologies, National Research Council, Rome, Italy
- University of Rome “La Sapienza”, Rome, Italy
| | - Marco D’Alessandro
- Institute of Cognitive Sciences and Technologies, National Research Council, Rome, Italy
| | - Hugo J. Spiers
- Institute of Behavioural Neuroscience, Department of Experimental Psychology, Division of Psychology and Language Sciences, University College London, United Kingdom
| | - Giovanni Pezzulo
- Institute of Cognitive Sciences and Technologies, National Research Council, Rome, Italy
| |
Collapse
|
7
|
The ventral midline thalamus coordinates prefrontal-hippocampal neural synchrony during vicarious trial and error. Sci Rep 2022; 12:10940. [PMID: 35768454 PMCID: PMC9243057 DOI: 10.1038/s41598-022-14707-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Accepted: 06/10/2022] [Indexed: 11/22/2022] Open
Abstract
When faced with difficult choices, the possible outcomes are considered through a process known as deliberation. In rats, deliberation is thought to be reflected by pause-and-reorienting behaviors, better known as vicarious trial and errors (VTEs). While VTEs are thought to require medial prefrontal cortex (mPFC) and dorsal hippocampal (dHPC) interactions, no empirical evidence has yet demonstrated such a dual requirement. The nucleus reuniens (Re) of the ventral midline thalamus is anatomically connected with both the mPFC and dHPC, is required for HPC-dependent spatial memory tasks, and is critical for mPFC-dHPC neural synchronization. Currently, it is unclear if, or how, the Re is involved in deliberation. Therefore, by examining the role of the Re on VTE behaviors, we can better understand the anatomical and physiological mechanisms supporting deliberation. Here, we examined the impact of Re suppression on VTE behaviors and mPFC-dHPC theta synchrony during asymptotic performance of a HPC-dependent delayed alternation (DA) task. Pharmacological suppression of the Re increased VTE behaviors that occurred with repetitive choice errors. These errors were best characterized as perseverative behaviors, in which some rats repeatedly selected a goal arm that previously yielded no reward. We then examined the impact of Re suppression on mPFC-dHPC theta synchrony during VTEs. We found that during VTEs, Re inactivation was associated with a reduction in mPFC-dHPC theta coherence and mPFC-to-dHPC theta directionality. Our findings suggest that the Re contributes to deliberation by coordinating mPFC-dHPC neural interactions.
Collapse
|
8
|
Miles JT, Kidder KS, Wang Z, Zhu Y, Gire DH, Mizumori SJY. A Machine Learning Approach for Detecting Vicarious Trial and Error Behaviors. Front Neurosci 2021; 15:676779. [PMID: 34305517 PMCID: PMC8292638 DOI: 10.3389/fnins.2021.676779] [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: 03/06/2021] [Accepted: 06/04/2021] [Indexed: 11/13/2022] Open
Abstract
Vicarious trial and error behaviors (VTEs) indicate periods of indecision during decision-making, and have been proposed as a behavioral marker of deliberation. In order to understand the neural underpinnings of these putative bridges between behavior and neural dynamics, researchers need the ability to readily distinguish VTEs from non-VTEs. Here we utilize a small set of trajectory-based features and standard machine learning classifiers to identify VTEs from non-VTEs for rats performing a spatial delayed alternation task (SDA) on an elevated plus maze. We also show that previously reported features of the hippocampal field potential oscillation can be used in the same types of classifiers to separate VTEs from non-VTEs with above chance performance. However, we caution that the modest classifier success using hippocampal population dynamics does not identify many trials where VTEs occur, and show that combining oscillation-based features with trajectory-based features does not improve classifier performance compared to trajectory-based features alone. Overall, we propose a standard set of features useful for trajectory-based VTE classification in binary decision tasks, and support previous suggestions that VTEs are supported by a network including, but likely extending beyond, the hippocampus.
Collapse
Affiliation(s)
- Jesse T Miles
- Graduate Program in Neuroscience, University of Washington, Seattle, WA, United States
| | - Kevan S Kidder
- Psychology Department, University of Washington, Seattle, WA, United States
| | - Ziheng Wang
- Psychology Department, University of Washington, Seattle, WA, United States
| | - Yiru Zhu
- Psychology Department, University of Washington, Seattle, WA, United States.,Undergraduate Neuroscience Program, University of Washington, Seattle, WA, United States
| | - David H Gire
- Graduate Program in Neuroscience, University of Washington, Seattle, WA, United States.,Psychology Department, University of Washington, Seattle, WA, United States
| | - Sheri J Y Mizumori
- Graduate Program in Neuroscience, University of Washington, Seattle, WA, United States.,Psychology Department, University of Washington, Seattle, WA, United States
| |
Collapse
|
9
|
Huynh T, Alstatt K, Abram SV, Schmitzer-Torbert N. Vicarious Trial-and-Error Is Enhanced During Deliberation in Human Virtual Navigation in a Translational Foraging Task. Front Behav Neurosci 2021; 15:586159. [PMID: 33912018 PMCID: PMC8072010 DOI: 10.3389/fnbeh.2021.586159] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Accepted: 03/01/2021] [Indexed: 11/18/2022] Open
Abstract
Foraging tasks provide valuable insights into decision-making as animals decide how to allocate limited resources (such as time). In rodents, vicarious trial-and-error (back and forth movements), or VTE, is an important behavioral measure of deliberation which is enhanced early in learning and when animals are presented with difficult decisions. Using new translational versions of a rodent foraging task (the "Movie Row" and "Candy Row"), humans navigated a virtual maze presented on standard computers to obtain rewards (either short videos or candy) offered after a variable delay. Decision latencies were longer when participants were presented with difficult offers, overrode their preferences, and when they accepted an offer after rejecting a previous offer. In these situations, humans showed VTE-like behavior, where they were more likely to pause and/or reorient one or more times before making a decision. Behavior on these tasks replicated previous results from the rodent foraging task ("Restaurant Row") and a human version lacking a navigation component ("Web-Surf") and revealed some species differences. Compared to survey measures of delay-discounting, willingness to wait for rewards in the foraging task was not related to willingness to wait for hypothetical rewards. And, smoking status (use of cigarettes or e-cigarettes) was associated with stronger discounting of hypothetical future rewards, but was not well-related to performance on the foraging tasks. In contrast, individuals with overweight or obese BMI (≥25) did not show stronger delay-discounting, but individuals with BMI ≥ 25, and especially females, showed reduced sensitivity to sunk-costs (where their decisions were less sensitive to irrecoverable investments of effort) and less deliberation when presented with difficult offers. These data indicate that VTE is a behavioral index of deliberation in humans, and further support the Movie and Candy Row as translational tools to study decision-making in humans with the potential to provide novel insights about decision-making that are relevant to public health.
Collapse
Affiliation(s)
- Thach Huynh
- Department of Psychology, Wabash College, Crawfordsville, IN, United States
| | - Keanan Alstatt
- Department of Psychology, Wabash College, Crawfordsville, IN, United States
| | - Samantha V. Abram
- Sierra Pacific Mental Illness Research Education and Clinical Centers, San Francisco Veterans Affairs Medical Center, Veterans Affairs San Francisco Healthcare System, University of California, San Francisco, San Francisco, CA, United States
- Department of Psychiatry, University of California, San Francisco, San Francisco, CA, United States
- Mental Health Service, Veterans Affairs San Francisco Healthcare System, San Francisco, CA, United States
| | | |
Collapse
|
10
|
A selective role for the
mPFC
during choice and deliberation, but not spatial memory retention over short delays. Hippocampus 2021; 31:690-700. [DOI: 10.1002/hipo.23306] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 11/09/2020] [Accepted: 01/09/2021] [Indexed: 01/29/2023]
|
11
|
Pezzulo G, Donnarumma F, Maisto D, Stoianov I. Planning at decision time and in the background during spatial navigation. Curr Opin Behav Sci 2019. [DOI: 10.1016/j.cobeha.2019.04.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
|
12
|
Santos-Pata D, Zucca R, López-Carral H, Verschure PFMJ. Modulating grid cell scale and intrinsic frequencies via slow high-threshold conductances: A simplified model. Neural Netw 2019; 119:66-73. [PMID: 31401527 DOI: 10.1016/j.neunet.2019.06.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 05/13/2019] [Accepted: 06/24/2019] [Indexed: 11/28/2022]
Abstract
Grid cells in the medial entorhinal cortex (MEC) have known spatial periodic firing fields which provide a metric for the representation of self-location and path planning. The hexagonal tessellation pattern of grid cells scales up progressively along the MEC's layer II dorsal-to-ventral axis. This scaling gradient has been hypothesized to originate either from inter-population synaptic dynamics as postulated by attractor networks, or from projected theta frequency waves to different axis levels, as in oscillatory models. Alternatively, cellular dynamics and specifically slow high-threshold conductances have been proposed to have an impact on the grid cell scale. To test the hypothesis that intrinsic hyperpolarization-activated cation currents account for both the scaled gradient and the oscillatory frequencies observed along the dorsal-to-ventral axis, we have modeled and analyzed data from a population of grid cells simulated with spiking neurons interacting through low-dimensional attractor dynamics. We observed that the intrinsic neuronal membrane properties of simulated cells were sufficient to induce an increase in grid scale and potentiate differences in the membrane potential oscillatory frequency. Overall, our results suggest that the after-spike dynamics of cation currents may play a major role in determining the grid cells' scale and that oscillatory frequencies are a consequence of intrinsic cellular properties that are specific to different levels of the dorsal-to-ventral axis in the MEC layer II.
Collapse
Affiliation(s)
- Diogo Santos-Pata
- Laboratory of Synthetic Perceptive, Emotive and Cognitive Systems (SPECS), Institute for Bioengineering of Catalonia (IBEC), Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
| | - Riccardo Zucca
- Laboratory of Synthetic Perceptive, Emotive and Cognitive Systems (SPECS), Institute for Bioengineering of Catalonia (IBEC), Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
| | - Héctor López-Carral
- Laboratory of Synthetic Perceptive, Emotive and Cognitive Systems (SPECS), Institute for Bioengineering of Catalonia (IBEC), Barcelona Institute of Science and Technology (BIST), Barcelona, Spain
| | - Paul F M J Verschure
- Laboratory of Synthetic Perceptive, Emotive and Cognitive Systems (SPECS), Institute for Bioengineering of Catalonia (IBEC), Barcelona Institute of Science and Technology (BIST), Barcelona, Spain; Institució Catalana de Recerca i Estudis Avançats (ICREA), Barcelona, Spain.
| |
Collapse
|