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Dong X, Wang Y, Liu Y, Li Y. Fear generalization modulated by shock intensity and protein synthesis inhibitor. Psychopharmacology (Berl) 2024:10.1007/s00213-024-06662-1. [PMID: 39105767 DOI: 10.1007/s00213-024-06662-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2024] [Accepted: 07/29/2024] [Indexed: 08/07/2024]
Abstract
RATIONALE Maladaptive fear responses, including sensitized threat reactions and overgeneralization, contribute to anxiety disorders such as generalized anxiety disorder and post-traumatic stress disorder. Although stress intensity influences the generation and extent of these maladaptive fears, the underlying mechanisms remain unclear. OBJECTIVES The present study examined whether varying footshock stress intensity and inhibition of protein synthesis have differential effect on fear sensitization and generalization in mice. METHODS Mice were subjected to a classic fear conditioning protocol involving five different levels of footshock intensities. Prior to fear acquisition, the protein synthesis inhibitor cycloheximide (CHX) was administered intraperitoneally. Fear sensitization to white noise and fear generalization to tones with frequencies differing from the conditioned tone were assessed at either 2 or 4 days after fear acquisition. RESULTS The results showed that, although varying shock intensities (except the lowest) led to a similar pattern of increased freezing during auditory cues in fear acquisition, the extent of both fear sensitization and generalization increased with the intensity of the footshock in the following days. As shock intensities increased, there was a proportional rise in sensitized fear to white noise and generalized freezing to tones with frequencies progressively closer to the conditioned stimulus. Mildest shocks did not induce discriminative conditioned fear memory, whereas the most intense shocks led to pronounced fear generalization. Administration of CHX before fear acquisition did not affect sensitized fear but reduced generalization of freezing to tones dissimilar from the conditioned stimulus in the group exposed to the most intense shock. CONCLUSIONS Our results suggest that maladaptive fear responses elicited by varying stress intensities exhibit distinct characteristics. The effect of CHX to prevent overgeneralization without affecting discriminative fear memory points to potential therapeutic approaches for fear-related disorders, suggesting the possibility of mitigating overgeneralization while preserving necessary fear discrimination.
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Affiliation(s)
- Xinwen Dong
- Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences, Beijing, China.
| | - Yunyun Wang
- Department of Neuroendocrine Pharmacology, School of Pharmacy, China Medical University, Shenyang, China
| | - Yudan Liu
- Department of Neuroendocrine Pharmacology, School of Pharmacy, China Medical University, Shenyang, China
| | - Yonghui Li
- Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of Sciences, Beijing, China
- Department of Psychology, University of Chinese Academy of Sciences, Beijing, China
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2
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Aydin AG, Lemenze A, Bieszczad KM. Functional diversities within neurons and astrocytes in the adult rat auditory cortex revealed by single-nucleus RNA sequencing. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.16.589831. [PMID: 38659766 PMCID: PMC11042262 DOI: 10.1101/2024.04.16.589831] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/26/2024]
Abstract
The mammalian cerebral cortex is composed of a rich diversity of cell types. Cortical cells are organized into networks that rely on their functional diversity to ultimately carry out a variety of sophisticated cognitive functions. To investigate the breadth of transcriptional diverse cell types in the sensory cortex, we have used single-nucleus RNA sequencing (snRNA-seq) in the auditory cortex of the adult rat. A variety of unique excitatory and inhibitory neuron types were identified. In addition, we report for the first time a diversity of astrocytes in the auditory cortex that may represent functionally unique subtypes. Together, these results pave the way for building models of how neurons in the sensory cortex work in concert with astrocytes at synapses to fulfill high-cognitive functions like learning and memory.
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3
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Graham G, Chimenti MS, Knudtson KL, Grenard DN, Co L, Sumner M, Tchou T, Bieszczad KM. Learning induces unique transcriptional landscapes in the auditory cortex. Hear Res 2023; 438:108878. [PMID: 37659220 PMCID: PMC10529106 DOI: 10.1016/j.heares.2023.108878] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 08/11/2023] [Accepted: 08/18/2023] [Indexed: 09/04/2023]
Abstract
Learning can induce neurophysiological plasticity in the auditory cortex at multiple timescales. Lasting changes to auditory cortical function that persist over days, weeks, or even a lifetime, require learning to induce de novo gene expression. Indeed, transcription is the molecular determinant for long-term memories to form with a lasting impact on sound-related behavior. However, auditory cortical genes that support auditory learning, memory, and acquired sound-specific behavior are largely unknown. Using an animal model of adult, male Sprague-Dawley rats, this report is the first to identify genome-wide changes in learning-induced gene expression within the auditory cortex that may underlie long-lasting discriminative memory formation of acoustic frequency cues. Auditory cortical samples were collected from animals in the initial learning phase of a two-tone discrimination sound-reward task known to induce sound-specific neurophysiological and behavioral effects. Bioinformatic analyses on gene enrichment profiles from bulk RNA sequencing identified cholinergic synapse (KEGG rno04725), extra-cellular matrix receptor interaction (KEGG rno04512), and neuroactive receptor interaction (KEGG rno04080) among the top biological pathways are likely to be important for auditory discrimination learning. The findings characterize candidate effectors underlying the early stages of changes in cortical and behavioral function to ultimately support the formation of long-term discriminative auditory memory in the adult brain. The molecules and mechanisms identified are potential therapeutic targets to facilitate experiences that induce long-lasting changes to sound-specific auditory function in adulthood and prime for future gene-targeted investigations.
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Affiliation(s)
- G Graham
- Neuroscience Graduate Program, Rutgers Univ., Piscataway, NJ, USA; Behavioral and Systems Neuroscience, Dept. of Psychology, Rutgers Univ., Piscataway, NJ, USA
| | - M S Chimenti
- Iowa Institute of Human Genetics, University of Iowa Carver College of Medicine, Iowa City, IA, USA
| | - K L Knudtson
- Iowa Institute of Human Genetics, University of Iowa Carver College of Medicine, Iowa City, IA, USA
| | - D N Grenard
- Behavioral and Systems Neuroscience, Dept. of Psychology, Rutgers Univ., Piscataway, NJ, USA
| | - L Co
- Behavioral and Systems Neuroscience, Dept. of Psychology, Rutgers Univ., Piscataway, NJ, USA
| | - M Sumner
- Behavioral and Systems Neuroscience, Dept. of Psychology, Rutgers Univ., Piscataway, NJ, USA
| | - T Tchou
- Behavioral and Systems Neuroscience, Dept. of Psychology, Rutgers Univ., Piscataway, NJ, USA
| | - K M Bieszczad
- Neuroscience Graduate Program, Rutgers Univ., Piscataway, NJ, USA; Behavioral and Systems Neuroscience, Dept. of Psychology, Rutgers Univ., Piscataway, NJ, USA; Rutgers Center for Cognitive Science, Rutgers Univ., Piscataway, NJ, USA; Dept. of Otolaryngology-Head and Neck Surgery, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ, USA.
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4
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Paraouty N, Yao JD, Varnet L, Chou CN, Chung S, Sanes DH. Sensory cortex plasticity supports auditory social learning. Nat Commun 2023; 14:5828. [PMID: 37730696 PMCID: PMC10511464 DOI: 10.1038/s41467-023-41641-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Accepted: 09/11/2023] [Indexed: 09/22/2023] Open
Abstract
Social learning (SL) through experience with conspecifics can facilitate the acquisition of many behaviors. Thus, when Mongolian gerbils are exposed to a demonstrator performing an auditory discrimination task, their subsequent task acquisition is facilitated, even in the absence of visual cues. Here, we show that transient inactivation of auditory cortex (AC) during exposure caused a significant delay in task acquisition during the subsequent practice phase, suggesting that AC activity is necessary for SL. Moreover, social exposure induced an improvement in AC neuron sensitivity to auditory task cues. The magnitude of neural change during exposure correlated with task acquisition during practice. In contrast, exposure to only auditory task cues led to poorer neurometric and behavioral outcomes. Finally, social information during exposure was encoded in the AC of observer animals. Together, our results suggest that auditory SL is supported by AC neuron plasticity occurring during social exposure and prior to behavioral performance.
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Affiliation(s)
- Nihaad Paraouty
- Center for Neural Science New York University, New York, NY, 10003, USA.
| | - Justin D Yao
- Department of Otolaryngology, Rutgers University, New Brunswick, NJ, 08901, USA
| | - Léo Varnet
- Laboratoire des Systèmes Perceptifs, UMR 8248, Ecole Normale Supérieure, PSL University, Paris, 75005, France
| | - Chi-Ning Chou
- Center for Computational Neuroscience, Flatiron Institute, Simons Foundation, New York, NY, USA
- School of Engineering & Applied Sciences, Harvard University, Cambridge, MA, 02138, USA
| | - SueYeon Chung
- Center for Neural Science New York University, New York, NY, 10003, USA
- Center for Computational Neuroscience, Flatiron Institute, Simons Foundation, New York, NY, USA
| | - Dan H Sanes
- Center for Neural Science New York University, New York, NY, 10003, USA
- Department of Psychology, New York University, New York, NY, 10003, USA
- Department of Biology, New York University, New York, NY, 10003, USA
- Neuroscience Institute, NYU Langone Medical Center, New York, NY, 10003, USA
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5
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Graham G, Chimenti MS, Knudtson KL, Grenard DN, Co L, Sumner M, Tchou T, Bieszczad KM. Learning induces unique transcriptional landscapes in the auditory cortex. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.04.15.536914. [PMID: 37090563 PMCID: PMC10120736 DOI: 10.1101/2023.04.15.536914] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/25/2023]
Abstract
Learning can induce neurophysiological plasticity in the auditory cortex at multiple timescales. Lasting changes to auditory cortical function that persist over days, weeks, or even a lifetime, require learning to induce de novo gene expression. Indeed, transcription is the molecular determinant for long-term memories to form with a lasting impact on sound-related behavior. However, auditory cortical genes that support auditory learning, memory, and acquired sound-specific behavior are largely unknown. This report is the first to identify in young adult male rats (Sprague-Dawley) genome-wide changes in learning-induced gene expression within the auditory cortex that may underlie the formation of long-lasting discriminative memory for acoustic frequency cues. Auditory cortical samples were collected from animals in the initial learning phase of a two-tone discrimination sound-reward task known to induce sound-specific neurophysiological and behavioral effects (e.g., Shang et al., 2019). Bioinformatic analyses on gene enrichment profiles from bulk RNA sequencing identified cholinergic synapse (KEGG 04725), extra-cellular matrix receptor interaction (KEGG 04512) , and neuroactive ligand-receptor interaction (KEGG 04080) as top biological pathways for auditory discrimination learning. The findings characterize key candidate effectors underlying changes in cortical function that support the initial formation of long-term discriminative auditory memory in the adult brain. The molecules and mechanisms identified are potential therapeutic targets to facilitate lasting changes to sound-specific auditory function in adulthood and prime for future gene-targeted investigations.
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Affiliation(s)
- G Graham
- Neuroscience Graduate Program, Rutgers Univ., Piscataway, NJ
- Behavioral and Systems Neuroscience, Dept. of Psychology, Rutgers Univ., Piscataway, NJ
| | - M S Chimenti
- Iowa Institute of Human Genetics, Univ. of Iowa Carver College of Medicine, Iowa City, IA
| | - K L Knudtson
- Iowa Institute of Human Genetics, Univ. of Iowa Carver College of Medicine, Iowa City, IA
| | - D N Grenard
- Behavioral and Systems Neuroscience, Dept. of Psychology, Rutgers Univ., Piscataway, NJ
| | - L Co
- Behavioral and Systems Neuroscience, Dept. of Psychology, Rutgers Univ., Piscataway, NJ
| | - M Sumner
- Behavioral and Systems Neuroscience, Dept. of Psychology, Rutgers Univ., Piscataway, NJ
| | - T Tchou
- Behavioral and Systems Neuroscience, Dept. of Psychology, Rutgers Univ., Piscataway, NJ
| | - K M Bieszczad
- Neuroscience Graduate Program, Rutgers Univ., Piscataway, NJ
- Behavioral and Systems Neuroscience, Dept. of Psychology, Rutgers Univ., Piscataway, NJ
- Rutgers Center for Cognitive Science, Rutgers Univ., Piscataway, NJ
- Dept. of Otolaryngology-Head and Neck Surgery, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ
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6
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Ye Y, Mattingly MM, Sunthimer MJ, Gay JD, Rosen MJ. Early-Life Stress Impairs Perception and Neural Encoding of Rapid Signals in the Auditory Pathway. J Neurosci 2023; 43:3232-3244. [PMID: 36973014 PMCID: PMC10162457 DOI: 10.1523/jneurosci.1787-22.2023] [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] [Received: 09/19/2022] [Revised: 01/24/2023] [Accepted: 03/03/2023] [Indexed: 03/29/2023] Open
Abstract
During developmental critical periods (CPs), early-life stress (ELS) induces cognitive deficits and alters neural circuitry in regions underlying learning, memory, and attention. Mechanisms underlying critical period plasticity are shared by sensory cortices and these higher neural regions, suggesting that sensory processing may also be vulnerable to ELS. In particular, the perception and auditory cortical (ACx) encoding of temporally-varying sounds both mature gradually, even into adolescence, providing an extended postnatal window of susceptibility. To examine the effects of ELS on temporal processing, we developed a model of ELS in the Mongolian gerbil, a well-established model for auditory processing. In both male and female animals, ELS induction impaired the behavioral detection of short gaps in sound, which are critical for speech perception. This was accompanied by reduced neural responses to gaps in auditory cortex, the auditory periphery, and auditory brainstem. ELS thus degrades the fidelity of sensory representations available to higher regions, and could contribute to well-known ELS-induced problems with cognition.SIGNIFICANCE STATEMENT In children and animal models, early-life stress (ELS) leads to deficits in cognition, including problems with learning, memory, and attention. Such problems could arise in part from a low-fidelity representation of sensory information available to higher-level neural regions. Here, we demonstrate that ELS degrades sensory responses to rapid variations in sound at multiple levels of the auditory pathway, and concurrently impairs perception of these rapidly-varying sounds. As these sound variations are intrinsic to speech, ELS may thus pose a challenge to communication and cognition through impaired sensory encoding.
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Affiliation(s)
- Yi Ye
- Hearing Research Group, Department of Anatomy and Neurobiology, Northeast Ohio Medical University, Rootstown, Ohio, 44272
- Brain Health Research Institute, Kent State University, Kent, Ohio, 44242
| | - Michelle M Mattingly
- Hearing Research Group, Department of Anatomy and Neurobiology, Northeast Ohio Medical University, Rootstown, Ohio, 44272
| | - Matthew J Sunthimer
- Hearing Research Group, Department of Anatomy and Neurobiology, Northeast Ohio Medical University, Rootstown, Ohio, 44272
| | - Jennifer D Gay
- Hearing Research Group, Department of Anatomy and Neurobiology, Northeast Ohio Medical University, Rootstown, Ohio, 44272
- Department of Otolaryngology, Head and Neck Surgery, Rutgers Robert Wood Johnson Medical School, New Brunswick, New Jersey, 08901
| | - Merri J Rosen
- Hearing Research Group, Department of Anatomy and Neurobiology, Northeast Ohio Medical University, Rootstown, Ohio, 44272
- Brain Health Research Institute, Kent State University, Kent, Ohio, 44242
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7
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Shang A, Bieszczad KM. Epigenetic mechanisms regulate cue memory underlying discriminative behavior. Neurosci Biobehav Rev 2022; 141:104811. [PMID: 35961385 DOI: 10.1016/j.neubiorev.2022.104811] [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: 03/31/2022] [Revised: 06/15/2022] [Accepted: 08/01/2022] [Indexed: 12/01/2022]
Abstract
The burgeoning field of neuroepigenetics has introduced chromatin modification as an important interface between experience and brain function. For example, epigenetic mechanisms like histone acetylation and DNA methylation operate throughout a lifetime to powerfully regulate gene expression in the brain that is required for experiences to be transformed into long-term memories. This review highlights emerging evidence from sensory models of memory that converge on the premise that epigenetic regulation of activity-dependent transcription in the sensory brain facilitates highly precise memory recall. Chromatin modifications may be key for neurophysiological responses to transient sensory cue features experienced in the "here and now" to be recapitulated over the long term. We conclude that the function of epigenetic control of sensory system neuroplasticity is to regulate the amount and type of sensory information retained in long-term memories by regulating neural representations of behaviorally relevant cues that guide behavior. This is of broad importance in the neuroscience field because there are few circumstances in which behavioral acts are devoid of an initiating sensory experience.
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Affiliation(s)
- Andrea Shang
- Dept. of Psychology - Behavioral and Systems Neuroscience, Rutgers University - New Brunswick, 152 Frelinghuysen Road, Piscataway, NJ 08854, USA
| | - Kasia M Bieszczad
- Dept. of Psychology - Behavioral and Systems Neuroscience, Rutgers University - New Brunswick, 152 Frelinghuysen Road, Piscataway, NJ 08854, USA; Rutgers Center for Cognitive Science (RuCCS), Rutgers University, Piscataway, NJ 08854, USA; Department of Otolaryngology - Head and Neck Surgery, Rutgers Robert Wood Johnson Medical School, New Brunswick, NJ 08854, USA.
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8
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Kim YH, Schrode KM, Engel J, Vicencio-Jimenez S, Rodriguez G, Lee HK, Lauer AM. Auditory Behavior in Adult-Blinded Mice. J Assoc Res Otolaryngol 2022; 23:225-239. [PMID: 35084628 PMCID: PMC8964904 DOI: 10.1007/s10162-022-00835-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Accepted: 12/31/2021] [Indexed: 10/19/2022] Open
Abstract
Cross-modal plasticity occurs when the function of remaining senses is enhanced following deprivation or loss of a sensory modality. Auditory neural responses are enhanced in the auditory cortex, including increased sensitivity and frequency selectivity, following short-term visual deprivation in adult mice (Petrus et al. Neuron 81:664-673, 2014). Whether or not these visual deprivation-induced neural changes translate into improved auditory perception and performance remains unclear. As an initial investigation of the effects of adult visual deprivation on auditory behaviors, CBA/CaJ mice underwent binocular enucleation at 3-4 weeks old and were tested on a battery of learned behavioral tasks, acoustic startle response (ASR), and prepulse inhibition (PPI) tests beginning at least 2 weeks after the enucleation procedure. Auditory brain stem responses (ABRs) were also measured to screen for potential effects of visual deprivation on non-behavioral hearing function. Control and enucleated mice showed similar tone detection sensitivity and frequency discrimination in a conditioned lick suppression test. Both groups showed normal reactivity to sound as measured by ASR in a quiet background. However, when startle-eliciting stimuli were presented in noise, enucleated mice showed decreased ASR amplitude relative to controls. Control and enucleated mice displayed no significant differences in ASR habituation, PPI tests, or ABR thresholds, or wave morphology. Our findings suggest that while adult-onset visual deprivation induces cross-modal plasticity at the synaptic and circuit levels, it does not substantially influence simple auditory behavioral performance.
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Affiliation(s)
- Ye-Hyun Kim
- Department of Otolaryngology-Head and Neck Surgery and Center for Hearing and Balance, Johns Hopkins University, Baltimore, MD, 21205, USA
| | - Katrina M Schrode
- Department of Otolaryngology-Head and Neck Surgery and Center for Hearing and Balance, Johns Hopkins University, Baltimore, MD, 21205, USA
| | - James Engel
- Department of Otolaryngology-Head and Neck Surgery and Center for Hearing and Balance, Johns Hopkins University, Baltimore, MD, 21205, USA
| | - Sergio Vicencio-Jimenez
- Department of Otolaryngology-Head and Neck Surgery and Center for Hearing and Balance, Johns Hopkins University, Baltimore, MD, 21205, USA
| | - Gabriela Rodriguez
- Cell, Molecular, Developmental Biology, and Biophysics (CMDB) Graduate Program, Johns Hopkins University, Baltimore, MD, USA
| | - Hey-Kyoung Lee
- Cell, Molecular, Developmental Biology, and Biophysics (CMDB) Graduate Program, Johns Hopkins University, Baltimore, MD, USA.,Solomon H. Snyder Department of Neuroscience, Johns Hopkins University, Baltimore, MD, USA.,Zanvyl-Krieger Mind/Brain Institute and Kavli Neuroscience Discovery Institute, Johns Hopkins University, Baltimore, MD, USA
| | - Amanda M Lauer
- Department of Otolaryngology-Head and Neck Surgery and Center for Hearing and Balance, Johns Hopkins University, Baltimore, MD, 21205, USA. .,Solomon H. Snyder Department of Neuroscience, Johns Hopkins University, Baltimore, MD, USA.
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Memory Specific to Temporal Features of Sound Is Formed by Cue-Selective Enhancements in Temporal Coding Enabled by Inhibition of an Epigenetic Regulator. J Neurosci 2021; 41:9192-9209. [PMID: 34544835 DOI: 10.1523/jneurosci.0691-21.2021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 07/23/2021] [Accepted: 08/18/2021] [Indexed: 11/21/2022] Open
Abstract
Recent investigation of memory-related functions in the auditory system have capitalized on the use of memory-modulating molecules to probe the relationship between memory and substrates of memory in auditory system coding. For example, epigenetic mechanisms, which regulate gene expression necessary for memory consolidation, are powerful modulators of learning-induced neuroplasticity and long-term memory (LTM) formation. Inhibition of the epigenetic regulator histone deacetylase 3 (HDAC3) promotes LTM, which is highly specific for spectral features of sound. The present work demonstrates for the first time that HDAC3 inhibition also enables memory for temporal features of sound. Adult male rats trained in an amplitude modulation (AM) rate discrimination task and treated with a selective inhibitor of HDAC3 formed memory that was highly specific to the AM rate paired with reward. Sound-specific memory revealed behaviorally was associated with a signal-specific enhancement in temporal coding in the auditory system; stronger phase locking that was specific to the rewarded AM rate was revealed in both the surface-recorded frequency following response and auditory cortical multiunit activity in rats treated with the HDAC3 inhibitor. Furthermore, HDAC3 inhibition increased trial-to-trial cortical response consistency (relative to naive and trained vehicle-treated rats), which generalized across different AM rates. Stronger signal-specific phase locking correlated with individual behavioral differences in memory specificity for the AM signal. These findings support that epigenetic mechanisms regulate activity-dependent processes that enhance discriminability of sensory cues encoded into LTM in both spectral and temporal domains, which may be important for remembering spectrotemporal features of sounds, for example, as in human voices and speech.SIGNIFICANCE STATEMENT Epigenetic mechanisms have recently been implicated in memory and information processing. Here, we use a pharmacological inhibitor of HDAC3 in a sensory model of learning to reveal the ability of HDAC3 to enable precise memory for amplitude-modulated sound cues. In so doing, we uncover neural substrates for memory's specificity for temporal sound cues. Memory specificity was supported by auditory cortical changes in temporal coding, including greater response consistency and stronger phase locking. HDAC3 appears to regulate effects across domains that determine specific cue saliency for behavior. Thus, epigenetic players may gate how sensory information is stored in long-term memory and can be leveraged to reveal the neural substrates of sensory details stored in memory.
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Rotondo EK, Bieszczad KM. Sensory cortical and subcortical auditory neurophysiological changes predict cue-specific extinction behavior enabled by the pharmacological inhibition of an epigenetic regulator during memory formation. Brain Res Bull 2021; 169:167-183. [PMID: 33515653 PMCID: PMC8591994 DOI: 10.1016/j.brainresbull.2021.01.016] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 01/03/2021] [Accepted: 01/22/2021] [Indexed: 11/19/2022]
Abstract
Extinction learning and memory have been broadly investigated at both behavioral and neural levels, but sensory system contributions to extinction processes have been less explored. Using a sound-reward extinction paradigm in male rats, we reveal both cortical and subcortical forms of plasticity associated with the cue-specificity of behavioral extinction memory. In the auditory cortex, frequency tuning narrowed by up to two-thirds of an octave around the remembered extinguished sound cue. Subcortical signals revealed in the auditory brainstem response (ABR) in the same animals developed smaller amplitudes of some (but not all) ABR peaks evoked by the extinguished sound frequency. Interestingly, treatment with an inhibitor of histone deacetylase 3 (HDAC3-i) facilitated both auditory cortical tuning bandwidth changes and changes in subcortical peak amplitude evoked only by the extinguished sound frequency. These neurophysiological changes were correlated to each other, and to the highly precise extinction behavior enabled by HDAC3-i (compared to vehicle controls). Thus, we show for the first time that HDAC3 regulates the specificity of sensory features consolidated in extinction memory. Further, the sensory cortical changes in tuning bandwidth recapitulate known effects of blocking HDAC3 to enhance cue specificity in other behavioral tasks. Therefore, the findings demonstrate how some forms of sensory neuroplasticity may encode specific sensory features of learning experiences in order to enable cue-specific behaviors.
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Affiliation(s)
- Elena K Rotondo
- Dept. of Psychology, Rutgers- The State University of New Jersey, Piscataway, NJ, 08854, United States
| | - Kasia M Bieszczad
- Dept. of Psychology, Rutgers- The State University of New Jersey, Piscataway, NJ, 08854, United States.
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