1
|
Katabi S, Adler A, Deffains M, Bergman H. Dichotomous activity and function of neurons with low- and high-frequency discharge in the external globus pallidus of non-human primates. Cell Rep 2023; 42:111898. [PMID: 36596302 DOI: 10.1016/j.celrep.2022.111898] [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: 02/14/2022] [Revised: 07/30/2022] [Accepted: 12/07/2022] [Indexed: 01/03/2023] Open
Abstract
To date, there is a consensus that there are at least two neuronal populations in the non-human primate (NHP) external globus pallidus (GPe): low-frequency discharge (LFD) and high-frequency discharge (HFD) neurons. Nevertheless, almost all NHP physiological studies have neglected the functional importance of LFD neurons. This study examined the discharge features of these two GPe neuronal subpopulations recorded in four NHPs engaged in a classical conditioning task with cues predicting reward, neutral and aversive outcomes. The results show that LFD neurons tended to burst, encoded the salience of behavioral cues, and exhibited correlated spiking activity. By contrast, the HFD neurons tended to pause, encoded cue valence, and exhibited uncorrelated spiking activity. Overall, these findings point to the dichotomic organization of the NHP GPe, which is likely to be critical to the implementation of normal basal ganglia functions and computations.
Collapse
Affiliation(s)
- Shiran Katabi
- Department of Medical Neuroscience, Institute of Medical Research Israel-Canada (IMRIC), The Hebrew University-Hadassah Medical School, 91120 Jerusalem, Israel.
| | - Avital Adler
- Department of Medical Neuroscience, Institute of Medical Research Israel-Canada (IMRIC), The Hebrew University-Hadassah Medical School, 91120 Jerusalem, Israel; The Edmond and Lily Safra Center for Brain Sciences, The Hebrew University, Jerusalem 91904, Israel
| | - Marc Deffains
- University of Bordeaux, UMR 5293, IMN, 33000 Bordeaux, France; CNRS, UMR 5293, IMN, 33000 Bordeaux, France
| | - Hagai Bergman
- Department of Medical Neuroscience, Institute of Medical Research Israel-Canada (IMRIC), The Hebrew University-Hadassah Medical School, 91120 Jerusalem, Israel; The Edmond and Lily Safra Center for Brain Sciences, The Hebrew University, Jerusalem 91904, Israel; Department of Neurosurgery, Hadassah Medical Center, Jerusalem 91120, Israel
| |
Collapse
|
2
|
Spontaneous pauses in firing of external pallidum neurons are associated with exploratory behavior. Commun Biol 2022; 5:612. [PMID: 35729350 PMCID: PMC9213498 DOI: 10.1038/s42003-022-03553-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Accepted: 06/02/2022] [Indexed: 11/25/2022] Open
Abstract
Spontaneous pauses in firing are the hallmark of external pallidum (GPe) neurons. However, the role of GPe pauses in the basal ganglia network remains unknown. Pupil size and saccadic eye movements have been linked to attention and exploration. Here, we recorded GPe spiking activity and the corresponding pupil sizes and eye positions in non-human primates. We show that pauses, rather than the GPe discharge rate per se, were associated with dilated pupils. In addition, following pause initiation there was a considerable increase in the rate of spontaneous saccades. These results suggest that pauses are a powerful mechanism by which the GPe may influence basal ganglia downstream structures and play a role in exploratory behavior. Integrated analysis of external pallidum (GPe) neuronal firing, pupil size, and saccadic movements in non-human primates reveals that pauses in GPe firing are associated with pupil dilation. These results suggest that pauses in GPe activity might influence downstream structures in the basal ganglia network and influence exploratory behavior.
Collapse
|
3
|
Ethanol-Sensitive Pacemaker Neurons in the Mouse External Globus Pallidus. Neuropsychopharmacology 2017; 42:1070-1081. [PMID: 27827370 PMCID: PMC5506786 DOI: 10.1038/npp.2016.251] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Revised: 10/26/2016] [Accepted: 10/27/2016] [Indexed: 11/27/2022]
Abstract
Although ethanol is one of the most widely used drugs, we still lack a full understanding of which neuronal subtypes are affected by this drug. Pacemaker neurons exert powerful control over brain circuit function, but little is known about ethanol effects on these types of neurons. Neurons in the external globus pallidus (GPe) generate pacemaker activity that controls basal ganglia, circuitry associated with habitual and compulsive drug use. We performed patch-clamp recordings from GPe neurons and found that bath application of ethanol dose-dependently decreased the firing rate of low-frequency GPe neurons, but did not alter the firing of high-frequency neurons. GABA or glutamate receptor antagonists did not block the ethanol effect. The GPe is comprised of a heterogeneous population of neurons. We used Lhx6-EGFP and Npas1-tdTm mice strains to identify low-frequency neurons. Lhx6 and Npas1 neurons exhibited decreased firing with ethanol, but only Npas1 neurons were sensitive to 10 mM ethanol. Large-conductance voltage and Ca2+-activated K+ (BK) channel have a key role in the ethanol effect on GPe neurons, as the application of BK channel inhibitors blocked the ethanol-induced firing decrease. Ethanol also increased BK channel open probability measured in single-channel recordings from Npas1-tdTm neurons. In addition, in vivo electrophysiological recordings from GPe showed that ethanol decreased the firing of a large subset of low-frequency neurons. These findings indicate how selectivity of ethanol effects on pacemaker neurons can occur, and enhance our understanding of the mechanisms contributing to acute ethanol effects on the basal ganglia.
Collapse
|
4
|
Hegeman DJ, Hong ES, Hernández VM, Chan CS. The external globus pallidus: progress and perspectives. Eur J Neurosci 2016; 43:1239-65. [PMID: 26841063 PMCID: PMC4874844 DOI: 10.1111/ejn.13196] [Citation(s) in RCA: 99] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Revised: 01/20/2016] [Accepted: 01/27/2016] [Indexed: 12/12/2022]
Abstract
The external globus pallidus (GPe) of the basal ganglia is in a unique and powerful position to influence processing of motor information by virtue of its widespread projections to all basal ganglia nuclei. Despite the clinical importance of the GPe in common motor disorders such as Parkinson's disease, there is only limited information about its cellular composition and organizational principles. In this review, recent advances in the understanding of the diversity in the molecular profile, anatomy, physiology and corresponding behaviour during movement of GPe neurons are described. Importantly, this study attempts to build consensus and highlight commonalities of the cellular classification based on existing but contentious literature. Additionally, an analysis of the literature concerning the intricate reciprocal loops formed between the GPe and major synaptic partners, including both the striatum and the subthalamic nucleus, is provided. In conclusion, the GPe has emerged as a crucial node in the basal ganglia macrocircuit. While subtleties in the cellular makeup and synaptic connection of the GPe create new challenges, modern research tools have shown promise in untangling such complexity, and will provide better understanding of the roles of the GPe in encoding movements and their associated pathologies.
Collapse
Affiliation(s)
- Daniel J Hegeman
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, 60611, USA
| | - Ellie S Hong
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, 60611, USA
| | - Vivian M Hernández
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, 60611, USA
| | - C Savio Chan
- Department of Physiology, Feinberg School of Medicine, Northwestern University, Chicago, IL, 60611, USA
| |
Collapse
|
5
|
Noblejas MI, Schechtman E, Adler A, Joshua M, Katabi S, Bergman H. Hold your pauses: external globus pallidus neurons respond to behavioural events by decreasing pause activity. Eur J Neurosci 2015; 42:2415-25. [PMID: 26263048 DOI: 10.1111/ejn.13041] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2015] [Revised: 07/26/2015] [Accepted: 08/03/2015] [Indexed: 11/29/2022]
Abstract
Awareness of its rich structural pathways has earned the external segment of the globus pallidus (GPe) recognition as a central figure within the basal ganglia circuitry. Interestingly, GPe neurons are uniquely identified by the presence of prominent pauses interspersed among a high-frequency discharge rate of 50-80 spikes/s. These pauses have an average pause duration of 620 ms with a frequency of 13/min, yielding an average pause activity (probability of a GPe neuron being in a pause) of (620 × 13)/(60 × 1000) = 0.13. Spontaneous pause activity has been found to be inversely related to arousal state. The relationship of pause activity with behavioural events remains to be elucidated. In the present study, we analysed the electrophysiological activity of 200 well-isolated GPe pauser cells recorded from four non-human primates (Macaque fascicularis) while they were engaged in similar classical conditioning tasks. The isolation quality of the recorded activity and the pauses were determined with objective automatic methods. The results showed that the pause probability decreased by 9.09 and 10.0%, and the discharge rate increased by 2.96 and 1.95%, around cue and outcome presentation, respectively. Analysis of the linear relationship between the changes in pause activity and discharge rate showed r(2) = 0.46 and r(2) = 0.66 upon cue onset and outcome presentation, respectively. Thus, pause activity is a pertinent element in short-term encoding of relevant behavioural events, and has a significant, but not exclusive, role in the modulation of GPe discharge rate around these events.
Collapse
Affiliation(s)
- Maria Imelda Noblejas
- Department of Neurobiology, Institute of Medical Research - Israel Canada (IMRIC), Hadassah Medical School, The Hebrew University, Jerusalem, 91120, Israel
| | - Eitan Schechtman
- Department of Neurobiology, Institute of Medical Research - Israel Canada (IMRIC), Hadassah Medical School, The Hebrew University, Jerusalem, 91120, Israel.,Edmond and Lily Safra Centre for Brain Sciences, The Hebrew University, Jerusalem, Israel
| | - Avital Adler
- Department of Neurobiology, Institute of Medical Research - Israel Canada (IMRIC), Hadassah Medical School, The Hebrew University, Jerusalem, 91120, Israel.,Edmond and Lily Safra Centre for Brain Sciences, The Hebrew University, Jerusalem, Israel
| | - Mati Joshua
- Department of Neurobiology, Institute of Medical Research - Israel Canada (IMRIC), Hadassah Medical School, The Hebrew University, Jerusalem, 91120, Israel.,Edmond and Lily Safra Centre for Brain Sciences, The Hebrew University, Jerusalem, Israel
| | - Shiran Katabi
- Department of Neurobiology, Institute of Medical Research - Israel Canada (IMRIC), Hadassah Medical School, The Hebrew University, Jerusalem, 91120, Israel
| | - Hagai Bergman
- Department of Neurobiology, Institute of Medical Research - Israel Canada (IMRIC), Hadassah Medical School, The Hebrew University, Jerusalem, 91120, Israel.,Edmond and Lily Safra Centre for Brain Sciences, The Hebrew University, Jerusalem, Israel
| |
Collapse
|