Deficits in habituation of cardiac arousal responses incurred by telencephalic ablation in goldfish, Carassius auratus, and their relation to other telencephalic functions

The effects of telencephalic ablation on the habituation of cardiac arousal responses in goldfish was studied. The ablation was performed either by ligating the telencephalon of habituated fish between stimulus presentations or by aspiration prior to habituation. The former technique caused dishabituation; the latter, a slower rate of habituation than that of sham-operated controls. The habituation deficit incurred by surgical ablation was found to decline with time, being small after 2 wk. The results are discussed in relation to other telencephalic involvements in behavior and to the plasticity of other parts of the brain which enables them to assume telencephalic functions.     

Localization of telencephalic regions concerned with habituation of cardiac and ventilatory responses associated with arousal in the goldfish (Carassius auratus).

54 goldfish were presented with a light-on stimulus at 2-min intervals, and their cardiac and ventilatory responses were monitored. Normal Ss, Ss with sham operations for telencephalic lesions, and Ss with bilateral electrolytic lesions of the telencephalon (anterior commissural and posterior telencephalic groups) were compared for responsiveness and habituation to regularly presented stimuli. There was no evident difference in responsiveness between the 4 groups, although 3 Ss with lesions in the regions ventralis pars dorsalis and ventralis pars ventralis gave fright responses to novel stimuli. Lesions in posterior telencephalic regions dorsalis pars centralis and ventralis pars intermedialis and at the telencephalic/diencephalic border close to the habenula caused significant impairment of habituation. (26 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Habituation of the EEG arousal response in rats: Short- and long-term effects, frequency specificity, and wake–sleep transfer.

In 3 experiments with 78 male Holtzman albino rats, presentation of auditory stimuli over interstimulus intervals (ISIs) of several minutes to sleeping Ss produced significant habituation of the EEG arousal response. The arousal response habituated to an asymptote after only 2 or 3 stimulus presentations. Little or no spontaneous recovery occurred between sessions separated by 24 or 72 hrs. The habituation produced by a single stimulus presentation was retained for at least 24 hrs, and orderly habituation was shown with a 24-hr ISI. Approximately 90% retention of habituation was shown 32 days following 10 stimulus presentations, and some degree of retention was shown for as long as 50 days. After habituation had reached a long-term asymptote, 600 stimulus presentations over 2-sec ISIs produced further response decrements, but these decrements recovered completely within a matter of minutes and responsiveness returned to the previously established long-term asymptote. Habituation was shown to be frequency-specific over both 24-hr and 32-day intervals. Habituation produced by stimulus presentations to awake Ss transferred to the condition in which stimuli were presented to sleeping Ss. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Habituation and sensitization of aggression in bullfrogs (Rana catesbeiana): Testing the dual-process theory of habituation.

The aggressive response of male bullfrogs (Rana catesbeiana) habituates with repeated broadcasts of acoustic stimuli simulating a new territorial neighbor. The effects of stimulus repetition rate and stimulus intensity on bullfrog aggressive responses were tested in a field experiment designed to test the assumptions of a dual-process theory of habituation. Synthetic advertisement calls were broadcast at 2 repetition rates and 2 intensities in a factorial design. Bullfrogs were more aggressive at the higher stimulus intensity at both repetition rates. Aggressive responses habituated more slowly at the higher stimulus intensity and slower repetition rate compared with other treatments. Several biotic and abiotic factors had small or negligible effects on aggressive responses. Although consistent with the operation of 2 opposing processes, habituation and sensitization, the data provide only partial support for the assumptions of dual-process theory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Habituation in goldfish (Carassius auratus) is impaired by increased interstimulus interval, interval variability, and telencephalic ablation.

Goldfish (Carassius auratus) were fitted with electrodes and buccal catheters for monitoring EKGs and ventilations, respectively. A 2-s "light-on" stimulus was repeatedly presented to groups of fish at fixed interstimulus intervals (ISIs) of 1 or 2 min or at variable ISIs with a mean duration of 1 or 2 min. Normal fish, fish with telencephalic ablation, and fish with sham operations were compared for responsiveness and habituation to repeatedly presented stimuli. The longer the ISI, the greater the number of stimuli that were required for habituation. Increased ISI variability also decreased the rate of habituation. Furthermore, fish with telencephalic ablation had significantly slower habituation rates with both fixed and variable ISI schedules. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A cardiac measure of cerebral asymmetries in infant auditory perception.

Examined the utility of cardiac habituation response recovery as a method for assessing infant cerebral asymmetries in auditory perception in a dichotic listening test. In a within-Ss design 12 3-mo-old infants were given a series of 4 10-trial tests during which their cardiac responses were habituated to a pair of dichotic speech syllables or music notes. The 10th trial in each test was a test trial on which one ear received its habituation stimulus while the other ear received a novel stimulus of the same type as the habituation pair (speech or music). Both stimulus type and ear receiving the novel stimulus were counterbalanced across tests. Overall, Ss' cardiac responses habituated during the tests and showed differential recovery to the novel stimuli. Specifically, greater response recovery occurred when a novel speech syllable was presented to the right, than to the left ear. Conversely, greater response recovery was found when a novel music note was presented to the left than to the right ear. Results indicate that young infants show a pattern of auditory perceptual asymmetries much like that found in older children and adults. Findings are consistent with the theory that in man the left hemisphere is superior at processing speech and the right hemisphere superior with nonspeech. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Dishabituating long-term memory for gustatory habituation in the cabbage looper, Trichoplusia ni.

The gustatory rejection response of the cabbage looper, Trichoplusia ni (Lepidoptera: Noctuidae), habituates to antifeedant compounds, allowing for the consumption of deterrent yet nontoxic plant materials. In the present study, we demonstrate that habituation to an antifeedant compound (quinine) persists through the moult between larval instars. As an indirect test of whether the memory was protein synthesis-dependent, we tested whether disrupting protein synthesis would block memory reconsolidation after a reminder. The results indicated that disrupting protein synthesis in habituated larvae following a reminder treatment (reexposure to quinine) eliminated the memory for habituation and restored the antifeedant properties of the quinine. We then examined whether the learned memory could be dishabituated and whether this would disrupt or eliminate long-term memory. We show that 6 hr after exposure to a novel/noxious stimulus (a second antifeedent, xanthotoxin) habituated larvae showed a transient dishabituation-like effect in which the quinine deterred feeding again. However, this effect did not permanently eliminate the habituation produced by the extended exposure as larvae tested 72 hr after xanthotoxin exposure again showed a willingness to consume the quinine treated leaves, indicating that the earlier habituation was still present. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Conditioning the unconditioned response: Modification of the rabbit's (Oryctolagus cuniculus) unconditioned nictitating membrane response.

Conditioning-specific reflex modification (CRM) occurs when classical conditioning modifies responding to a unconditioned stimulus/stimuli (UCS) in the absence of a conditioned stimulus (CS). Three experiments monitored rabbit (Oryctolagus cuniculus) nictitating membrane unconditioned responses to 5 intensities and 4 durations of periorbital electrical stimulation before and after CS or UCS manipulation. CRM occurred after 12 days of CS-UCS pairings but not following unpaired CS/UCS presentations or restraint. CRM survived CS-alone and CS/UCS-unpaired extinction of the conditioned response (CR) but not presentations of the UCS alone, although CRs remained intact. Thus, CRs could be weakened without eliminating CRM and CRM could be weakened without eliminating CRs. Data indicate CRM is a reliable, associative effect that is more than a generalized CR and may not be explained by habituation, stimulus generalization, contextual conditioning, or bidirectional conditioning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Differential sensitization, retention, and generalization of habituation in two response systems in the blowfly (Calliphora vomitoira).

Conducted 3 experiments with 95 blowflies to elicit a cardiac disturbance and a motor response by the same moving visual stimulus. In Exp I, the habituation of these responses developed at an equal rate during stimulus repetition. After a rest period, whereas habituation of motor responses was completely retained, a substantial recovery of cardiac responses was observed. The use of distributed trials in Exp II helped to dissociate the influence of sensitization and habituation processes on the behavioral outcome. Habituation of motor responses, in addition to a longer retention, appeared to be more easily generalized after a spatial displacement of the stimulus in Exp III. Data support the hypothesis that habituation processes develop independently in different response systems, even if they have the same sensory input. The faster reversibility of habituation of cardiac responses is discussed, with reference to a preparatory function for locomotor behavior. (41 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Analysis and neural network modeling of the nonlinear correlates of habituation in the vestibulo-ocular reflex

Through the process of habituation, continued exposure to low-frequency (0.01 Hz) rotation in the dark produced suppression of the low-frequency response of the vestibulo-ocular reflex (VOR) in goldfish. The response did not decay gradually, as might be expected from an error-driven learning process, but displayed several nonlinear and nonstationary features. They included asymmetrical response suppression, magnitude-dependent suppression for lower- but not higher-magnitude head rotations, and abrupt-onset suppressions suggestive of a switching mechanism. Microinjection of lidocaine into the vestibulocerebellum of habituated goldfish resulted in a temporary dishabituation. This suggests that the vestibulocerebellum mediates habituation, presumably through Purkinje cell inhibition of vestibular nuclei neurons. The habituated VOR data were simulated with a feed-forward, nonlinear neural network model of the VOR in which only Purkinje cell inhibition of vestibular nuclei neurons was varied. The model suggests that Purkinje cell inhibition may switch in to introduce nonstationarities, and cause asymmetry and magnitude-dependency in the VOR to emerge from the essential nonlinearity of vestibular nuclei neurons.     

Effects of mesencephalic reticular formation lesions on habituation of startle and lick suppression responses in the rat.

In 2 experiments with 43 male albino Holtzman rats, extensive damage to the mesencephalic reticular formation (MRF) altered long-term habituation of the acoustic startle response without disrupting short-term habituation. Ss with MRF lesions, although initially neither more nor less responsive than controls, could not attain as low a long-term asymptote of habituation as could control Ss with repeated presentations of an auditory stimulus. Changing the quality of the auditory stimulus abolished the asymptotic difference in responsiveness. With repeated presentations of the 2nd auditory stimulus, control Ss again reached a significantly lower long-term habituation asymptote than did Ss with MRF lesions. The course of long-term habituation for the 2 groups suggested a disruption of an extrinsic, inhibitory habituation process by the lesions. The effects of MRF lesions were specific to the acoustic startle response. Control Ss and those with lesions showed comparable response levels, short-term habituation, and long-term habituation of the lick suppression response. Responsiveness and habituation to tactile stimuli were comparable for the 2 groups on both lick suppression and startle response measures. (32 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Effect of stressor intensity on habituation and sensitization of glucocorticoid responses in rats.

Studied the effect of stressor intensity on habituation/sensitization of the adrenocortical stress response (ASR) in rats. When lower intensity shock was given, the response first habituated to no-shock control levels but later returned to the same magnitude as seen on the 1st probe day. Plasma corticosterone responses given higher intensity shock never habituated and instead demonstrated an increased response indicative of sensitization. Responsiveness to exogenous adrenocorticotropin 24 hr after the last stress session was monotonically related to the intensity of the stressor presented during the experimental sessions. Data are consistent with the rule from habituation literature that stimulus intensity is inversely related to the magnitude of habituation and extend the dual process theory of P. M. Groves and R. F. Thompson (see record 1971-02046-001) to an endocrine respondent. The data also suggest that an explanation as to the discrepancies in the literature concerning ASR to repeated presentation of stressors may relate to differences in the stressor parameters used. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Neuroethological studies of reflex plasticity in intact Aplysia..

Multi-unit recording of siphon nerve activity in intact Aplysia californica (a marine gastropod) with chronically implanted cuff electrodes provided a monitor of activity in a central pattern generator, the Interneuron II (Int II) network, which produces large siphon and gill contractions both spontaneously and after tactile stimulation of the siphon. The phase–response curve of the Int II oscillator for single stimuli at different phases of the cycle showed a "refractory" period early in the cycle, after which most stimuli phase advanced the oscillator and caused a short-latency Int II burst and a large contraction. The amplitude of gill withdrawal and the duration of siphon withdrawal in response to different stimulus intensities depended on whether an Int II burst was triggered. Activation of the Int II oscillator transformed the reflex from one that was graded smoothly with stimulus intensity to one in which nearly maximal responses were elicited even by weak stimuli. Entrainment and habituation training both involved monotonous repetition of a stimulus at specific intervals. With repeated siphon stimuli, nearly maximal reflex responses were maintained in intact Ss as long as the Int II oscillator was entrained, whereas habituation was associated primarily with failure to entrain the oscillator. Sensitized Ss showed significantly more triggered Int II burst than did controls. Digital spike-train analysis indicated that individual siphon motoneurons showed significantly increased background activity that often persisted for several minutes. (41 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Song syllable discrimination by song sparrows (Melospiza melodia).

A habituation test paradigm was used to examine the responses of free-living territorial adult male song sparrows (Melospiza melodia) to a range synthetic songs. The three-phrased test songs differed from one another in having either conspecific or heterospecific (swamp sparrow, M. georgiana) syllables, or silence, in the second phrase. Subjects were exposed to repeated presentations of one song type until their approach distance to a loudspeaker increased. In one experiment, birds were habituated with a song consisting of three phrases of song sparrow syllables and then tested for generalization to either novel song sparrow syllables in the second phrase, swamp sparrow syllables, or silence. Birds discriminated between song sparrow syllables on two response measures, and between song sparrow and swamp sparrow syllables on one measure. In a second experiment, after habituation to a song with swamp sparrow syllables in the second phrase, birds did not generalize to novel song sparrow syllables, but they did generalize to novel swamp sparrow syllables. The results further suggest that subtle species-specific differences in note structure within syllables are discriminated by song sparrows and potentially provide an adequate basis for individual recognition by song. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Stimulus- and motivation-specific sensitization and redirection of aggression in the three-spined stickleback (Gasterosteus aculeatus).

Studied 50 male 3-spined sticklebacks to examine the incremental processes of sensitization-habituation. Findings indicate that the incremental processes are analogous to those postulated by a dual-process theory of habituation based on acute neurobiological preparations. Sensitization appears to have both stimulus- and motivation-specific components and appears to sensitize over repeated experiences. Sensitization may serve to maintain behavior during the presence of the eliciting stimulus while the inhibitory component (habituation) is consolidating independently. Finally, the motivation-specific component may explain the increased aggression, during stimulus presentation, directed to neighbors to which the S fish had already habituated. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Mesencephalic reticular formation lesions made after habituation training abolish long-term habituation of the acoustic startle response in rats.

Lesions to the mesencephalic reticular formation (MRF) in rats severely attenuate the acquisition of long-term habituation of the startle response when the lesions are made prior to habituation training. The present experiments extend the finding of habituation deficits to animals with MRF damage made after the animals have habituated to an auditory stimulus. Following habitation training, some animals received lesions to the MRF. The startle amplitudes of these animals immediately changed from control levels to levels indistinguishable from those of animals that never habituated across days—animals with MRF lesions made prior to habituation training. The mechanism responsible for long-term habituation appears to be a progressive increase in activity within a long-term habituation pathway extrinsic to the reflex circuit for the startle response, but the synaptic mechanisms responsible for this change are unknown. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Potentiation of the acoustic startle response by a conditioned stimulus paired with acoustic startle stimulus in rats.

The hypothesis that the standard acoustic startle habituation paradigm contains the elements of Pavlovian fear conditioning was tested. In a potentiated startle response paradigm, a startle stimulus and a light conditioned stimulus (CS) were paired. A startle stimulus then was tested alone or following the CS. Freezing behavior was measured to index conditioned fear. The startle response was potentiated on CS trials, and rats froze more in CS than in non-CS periods. In Experiment 1, response to a previously habituated, weak startle stimulus was potentiated. In Experiment 2, response to the same stimulus used as the unconditioned stimulus (US) in training was potentiated. This CS-potentiated response retarded the course of response decrements over training sessions as compared with an explicitly unpaired control group. Conditioned fear is a standard feature of this habituation paradigm, serves to potentiate the startle response, and provides an associative dimension lacking in the habituation process per se. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Vestibular habituation in paralyzed cats.

Studied the role of the eye movement response in the production of vestibular habituation in 12 cats. One group of Ss was subjected to an habituation series of 15 unilateral caloric irrigations while paralyzed with gallamine triethiodide. A 2nd group underwent an identical habituation procedure but was not paralyzed. Tests conducted following recovery from paralysis showed that the responses of the previously is Ss were habituated and did not differ from the responses of Ss habituated in a normal manner. Data support a central origin for the phenomenon of vestibular habituation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Varieties of habituation in the chinchilla (Chinchilla lanigera).

Examined multiple behaviors in 12 adult female chinchillas. Basal respiration and struggle activity during conditions of physical restraint, and head-shake responses (HSRs) elicited by a stream of air directed in the ear, all exhibited within-session decrement which recovered only partially within 24 hr. Complete recovery of the habituated HSR and basal respiration required more than 4 days. Potentiation of habituation occurred for struggle activity only. Neither transfer of habituation nor dishabituation, examined with the HSR only, was obtained. Differential sensitivity to concurrent stimulation was found between the various response systems. In addition, rates of habituation among response systems were uncorrelated. The combined results support a multiprocess interpretation of habituatory response decrement. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Lack of contextual modulation of habituated neuroendocrine responses to repeated audiogenic stress.

Exposure to stress reliably activates the hypothalamo–pituitary–adrenocortical (HPA) axis response in rodents, which is significantly reduced (habituated) following repeated exposures. In the current study, it was first established that HPA axis response habituation to repeated loud noise lasted for at least 4 weeks in rats. In the next experiment, a contextual extinction procedure following repeated loud noise exposures failed to restore the habituated HPA axis response. Although an additional study indicated some recovery of responses when the context was modified on a test day following habituation, this effect could be mostly attributed to the familiarity with the contextual cues. A final study confirmed that rats could distinguish between the contexts used and further indicated that context preexposures reduce acute HPA axis responses to loud noise. These studies therefore provide no support for the hypothesis that contextual cues regulate HPA axis response habituation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)