Inhibition of the expression of conditioned cardiac responses in the developing rat

Hunt, Pamela S.; Hess, Maureen F.; Campbell, Byron A.

doi:10.1002/(sici)1098-2302(199811)33:3<221::aid-dev3>3.0.co;2-t

Cited by 17 publications

(14 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…olfactory) senses precedes that of the auditory system in the rat (see Alberts and Gubernick, for review). Further, the functional onset of the auditory system precedes that of the visual system across a wide range of species (Gottlieb and Klopfer, ; Hyson and Rudy, ; Hunt et al ., ). Indeed, rats express a learned fear response to an odour CS as early as P12 before they express the same learned response to an auditory CS (Kucharski and Spear, ; Campbell and Ampuero, ), and express a learned fear response to an auditory CS before they express the same learned response to a visual CS (Hunt and Campbell, ).…”

Section: Learned Fear To a Discrete Cuementioning

confidence: 97%

Developmental rodent models of fear and anxiety: from neurobiology to pharmacology

Ganella

Kim

2014

British J Pharmacology

View full text Add to dashboard Cite

Anxiety disorders pose one of the biggest threats to mental health in the world, and they predominantly emerge early in life. However, research of anxiety disorders and fear-related memories during development has been largely neglected, and existing treatments have been developed based on adult models of anxiety. The present review describes animal models of anxiety disorders across development and what is currently known of their pharmacology. To summarize, the underlying mechanisms of intrinsic 'unlearned' fear are poorly understood, especially beyond the period of infancy. Models using 'learned' fear reveal that through development, rats exhibit a stress hyporesponsive period before postnatal day 10, where they paradoxically form odour-shock preferences, and then switch to more adult-like conditioned fear responses. Juvenile rats appear to forget these aversive associations more easily, as is observed with the phenomenon of infantile amnesia. Juvenile rats also undergo more robust extinction, until adolescence where they display increased resistance to extinction. Maturation of brain structures, such as the amygdala, prefrontal cortex and hippocampus, along with the different temporal recruitment and involvement of various neurotransmitter systems (including NMDA, GABA, corticosterone and opioids) are responsible for these developmental changes. Taken together, the studies described in this review highlight that there is a period early in development where rats appear to be more robust in overcoming adverse early life experience. We need to understand the fundamental pharmacological processes underlying anxiety early in life in order to take advantage of this period for the treatment of anxiety disorders.

show abstract

Section: Learned Fear To a Discrete Cuementioning

confidence: 97%

Developmental rodent models of fear and anxiety: from neurobiology to pharmacology

Ganella

Kim

2014

British J Pharmacology

View full text Add to dashboard Cite

show abstract

“…For example, cerebellar delay eye blink conditioning is known to emerge in rats between postnatal days (PND) 17 -24 (Stanton et al 1992;Ivkovich et al 2000), hippocampal memory between PNDs 18-23 (Rudy and Morledge 1994), and learned fear responses to odor conditioned stimuli as early as PND 12 (Hunt et al 1998). By comparison, much less is known about the ontogeny of learning and memory during later stages of development, including adolescence.…”

mentioning

confidence: 92%

The ontogeny of learned inhibition

Meyer

Bucci

2014

Learn. Mem.

View full text Add to dashboard Cite

Previous studies have examined the maturation of learning and memory abilities during early stages of development. By comparison, much less is known about the ontogeny of learning and memory during later stages of development, including adolescence. In Experiment 1, we tested the ability of adolescent and adult rats to learn a Pavlovian negative occasion setting task. This procedure involves learning to inhibit a behavioral response when signaled by a cue in the environment. During reinforced trials, a target stimulus (a tone) was presented and immediately followed by a food reward. On nonreinforced trials, a feature stimulus (a light) was presented 5 sec prior to the tone and indicated the absence of reward following presentation of the tone. Both adult and adolescent rats learned to discriminate between two different trial types and withhold responding when the light preceded the tone. However, adolescent rats required more sessions than adults to discriminate between reinforced and nonreinforced trials. The results of Experiment 2 revealed that adolescents could learn the task rules but were specifically impaired in expressing that learning in the form of withholding behavior on nonreinforced trials. In Experiment 3, we found that adolescents were also impaired in learning a different version of the task in which the light and tone were presented simultaneously during the nonreinforced trials. These findings add to existing literature by indicating that impairments in inhibitory behavior during adolescence do not reflect an inability to learn to inhibit a response, but instead reflect a specific deficit in expressing that learning.

show abstract

“…However, important conditioned response (CR)‐specific dissociations are evidenced in pre‐weanling rats. Conditioned freezing emerges at a younger age than conditioned cardiovascular responses, which emerge prior to conditioned fear potentiation of startle (Hunt & Campbell, ; Hunt, Hess, & Campbell, ). Richardson and coworkers (Richardson & Fan, ; Yap, Stapinski, & Richardson, ) have shown that fear memory expression is appropriate to the rat's age at training, rather than testing.…”

Section: Introductionmentioning

confidence: 99%

Infant stress exposure produces persistent enhancement of fear learning across development

Quinn

Skipper

Claflin

2013

Developmental Psychobiology

View full text Add to dashboard Cite

In recent years, it has become increasingly clear that early life stress experiences persistently impact subsequent physiological, cognitive, and emotional responses. In cases of trauma, these early experiences can result in anxiety disorders such as phobias and posttraumatic stress disorder. In the present paper, we examined the effects of infant footshock stress exposure at postnatal day (PND) 17 on subsequent contextual fear conditioning at postnatal days 18 (Experiment 1), 24 (Experiment 2), or 90 (Experiment 3). In each experiment, PND17 footshock stress exposure enhanced later fear conditioning, indicating that the stress enhancement of fear learning (SEFL) persists throughout development. Memory for the original stress exposure context was gradually forgotten, with significant fear expression evident at PND20, and a complete lack of fear expression in that same context at PND90. These data suggest that the stress-enhancing component of infant fear learning is dissociable from the infant contextual fear memory per se. In other words, early life stress produces persistent effects on subsequent cognition that are independent of the memory for that early life event.

show abstract

Inhibition of the expression of conditioned cardiac responses in the developing rat

Cited by 17 publications

References 34 publications

Developmental rodent models of fear and anxiety: from neurobiology to pharmacology

Developmental rodent models of fear and anxiety: from neurobiology to pharmacology

The ontogeny of learned inhibition

Infant stress exposure produces persistent enhancement of fear learning across development

Contact Info

Product

Resources

About