Different projections of the central amygdaloid nucleus mediate autonomic and behavioral correlates of conditioned fear

Joseph Ledoux, J. Iwata, P. Cicchetti, D. J. Reis

Research output: Contribution to journalArticle

Abstract

The purpose of the present study was to determine whether lesions of areas projected to by the central amygdaloid nucleus (ACE) would disrupt the classical conditioning of autonomic and/or behavioral emotional responses. The areas studied included 3 projection targets of the ACE: the lateral hypothalamic area (LH), midbrain central gray (CG) region, and bed nucleus of the stria terminalis (BNST). Lesions were made either electrolytically or by microinjection of ibotenic acid, which destroys local neurons without interrupting fibers of passage. Two weeks later, the animals were clinically conditioned by pairing an acoustic stimulus with footshock. The next day, conditioned changes in autonomic activity (increases in arterial pressure) and emotional behavior ('freezing', or the arrest of somatomotor activity) evoked by the acoustic conditioned stimulus (CS) were measured during extinction trials. Electrolytic and ibotenic acid lesions of the LH interfered with the conditioned arterial pressure response, but did not affect conditioned freezing. Electrolytic lesions of the rostral CG disrupted conditioned freezing but not conditioned changes in arterial pressure. Ibotenic acid injected into the rostral CG reduced neither the arterial pressure nor the freezing response. Injection of ibotenic acid in the caudal CG, like electrolytic lesions of the rostral CG, disrupted the freezing, but not the arterial pressure response. Injection of ibotenic acid into the BNST had no effect on either response. These data demonstrate that neurons in the LH are involved in the autonomic, but not the behavioral, conditioned response pathway, whereas neurons in the caudal CG are involved in the behavioral, but not the autonomic, pathway. Different efferent projections of the central amygdala thus appear to mediate the behavioral and autonomic concomitants of conditioned fear.

Original languageEnglish (US)
Pages (from-to)2517-2529
Number of pages13
JournalJournal of Neuroscience
Volume8
Issue number7
StatePublished - 1988

Fingerprint

Ibotenic Acid
Freezing
Fear
Lateral Hypothalamic Area
Arterial Pressure
Septal Nuclei
Neurons
Acoustics
Autonomic Pathways
Periaqueductal Gray
Injections
Classical Conditioning
Microinjections
Central Amygdaloid Nucleus

ASJC Scopus subject areas

  • Neuroscience(all)

Cite this

Different projections of the central amygdaloid nucleus mediate autonomic and behavioral correlates of conditioned fear. / Ledoux, Joseph; Iwata, J.; Cicchetti, P.; Reis, D. J.

In: Journal of Neuroscience, Vol. 8, No. 7, 1988, p. 2517-2529.

Research output: Contribution to journalArticle

@article{db25b5a6c89e4b8792e8a39c8ac81c92,
title = "Different projections of the central amygdaloid nucleus mediate autonomic and behavioral correlates of conditioned fear",
abstract = "The purpose of the present study was to determine whether lesions of areas projected to by the central amygdaloid nucleus (ACE) would disrupt the classical conditioning of autonomic and/or behavioral emotional responses. The areas studied included 3 projection targets of the ACE: the lateral hypothalamic area (LH), midbrain central gray (CG) region, and bed nucleus of the stria terminalis (BNST). Lesions were made either electrolytically or by microinjection of ibotenic acid, which destroys local neurons without interrupting fibers of passage. Two weeks later, the animals were clinically conditioned by pairing an acoustic stimulus with footshock. The next day, conditioned changes in autonomic activity (increases in arterial pressure) and emotional behavior ('freezing', or the arrest of somatomotor activity) evoked by the acoustic conditioned stimulus (CS) were measured during extinction trials. Electrolytic and ibotenic acid lesions of the LH interfered with the conditioned arterial pressure response, but did not affect conditioned freezing. Electrolytic lesions of the rostral CG disrupted conditioned freezing but not conditioned changes in arterial pressure. Ibotenic acid injected into the rostral CG reduced neither the arterial pressure nor the freezing response. Injection of ibotenic acid in the caudal CG, like electrolytic lesions of the rostral CG, disrupted the freezing, but not the arterial pressure response. Injection of ibotenic acid into the BNST had no effect on either response. These data demonstrate that neurons in the LH are involved in the autonomic, but not the behavioral, conditioned response pathway, whereas neurons in the caudal CG are involved in the behavioral, but not the autonomic, pathway. Different efferent projections of the central amygdala thus appear to mediate the behavioral and autonomic concomitants of conditioned fear.",
author = "Joseph Ledoux and J. Iwata and P. Cicchetti and Reis, {D. J.}",
year = "1988",
language = "English (US)",
volume = "8",
pages = "2517--2529",
journal = "Journal of Neuroscience",
issn = "0270-6474",
publisher = "Society for Neuroscience",
number = "7",

}

TY - JOUR

T1 - Different projections of the central amygdaloid nucleus mediate autonomic and behavioral correlates of conditioned fear

AU - Ledoux, Joseph

AU - Iwata, J.

AU - Cicchetti, P.

AU - Reis, D. J.

PY - 1988

Y1 - 1988

N2 - The purpose of the present study was to determine whether lesions of areas projected to by the central amygdaloid nucleus (ACE) would disrupt the classical conditioning of autonomic and/or behavioral emotional responses. The areas studied included 3 projection targets of the ACE: the lateral hypothalamic area (LH), midbrain central gray (CG) region, and bed nucleus of the stria terminalis (BNST). Lesions were made either electrolytically or by microinjection of ibotenic acid, which destroys local neurons without interrupting fibers of passage. Two weeks later, the animals were clinically conditioned by pairing an acoustic stimulus with footshock. The next day, conditioned changes in autonomic activity (increases in arterial pressure) and emotional behavior ('freezing', or the arrest of somatomotor activity) evoked by the acoustic conditioned stimulus (CS) were measured during extinction trials. Electrolytic and ibotenic acid lesions of the LH interfered with the conditioned arterial pressure response, but did not affect conditioned freezing. Electrolytic lesions of the rostral CG disrupted conditioned freezing but not conditioned changes in arterial pressure. Ibotenic acid injected into the rostral CG reduced neither the arterial pressure nor the freezing response. Injection of ibotenic acid in the caudal CG, like electrolytic lesions of the rostral CG, disrupted the freezing, but not the arterial pressure response. Injection of ibotenic acid into the BNST had no effect on either response. These data demonstrate that neurons in the LH are involved in the autonomic, but not the behavioral, conditioned response pathway, whereas neurons in the caudal CG are involved in the behavioral, but not the autonomic, pathway. Different efferent projections of the central amygdala thus appear to mediate the behavioral and autonomic concomitants of conditioned fear.

AB - The purpose of the present study was to determine whether lesions of areas projected to by the central amygdaloid nucleus (ACE) would disrupt the classical conditioning of autonomic and/or behavioral emotional responses. The areas studied included 3 projection targets of the ACE: the lateral hypothalamic area (LH), midbrain central gray (CG) region, and bed nucleus of the stria terminalis (BNST). Lesions were made either electrolytically or by microinjection of ibotenic acid, which destroys local neurons without interrupting fibers of passage. Two weeks later, the animals were clinically conditioned by pairing an acoustic stimulus with footshock. The next day, conditioned changes in autonomic activity (increases in arterial pressure) and emotional behavior ('freezing', or the arrest of somatomotor activity) evoked by the acoustic conditioned stimulus (CS) were measured during extinction trials. Electrolytic and ibotenic acid lesions of the LH interfered with the conditioned arterial pressure response, but did not affect conditioned freezing. Electrolytic lesions of the rostral CG disrupted conditioned freezing but not conditioned changes in arterial pressure. Ibotenic acid injected into the rostral CG reduced neither the arterial pressure nor the freezing response. Injection of ibotenic acid in the caudal CG, like electrolytic lesions of the rostral CG, disrupted the freezing, but not the arterial pressure response. Injection of ibotenic acid into the BNST had no effect on either response. These data demonstrate that neurons in the LH are involved in the autonomic, but not the behavioral, conditioned response pathway, whereas neurons in the caudal CG are involved in the behavioral, but not the autonomic, pathway. Different efferent projections of the central amygdala thus appear to mediate the behavioral and autonomic concomitants of conditioned fear.

UR - http://www.scopus.com/inward/record.url?scp=0023677407&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0023677407&partnerID=8YFLogxK

M3 - Article

VL - 8

SP - 2517

EP - 2529

JO - Journal of Neuroscience

JF - Journal of Neuroscience

SN - 0270-6474

IS - 7

ER -