Habituation Patterns Research Articles

Pervasive hyperactivity and long-term learning impairments in rats with induced micrencephaly from prenatal exposure to methylazoxymethanol

Pregnant Long-Evans rats were given a single i.p. injection of 30 mg/kg of methylazoxymethanol (MAM) acetate or saline on day 14 of gestation (vaginal plug = day 0). All litters were reduced to 8 at birth and were reared by their biological dams. Between 49–192 days of age all offspring were examined on open-field, figure-8 (at two different ages), and hole-board tests of activity, as well as passive avoidance and Biel water maze tests of learning (also at two different ages). The MAM offspring showed no increase in mortality, but weighed less than controls, a difference that remained relatively constant throughout the experiment. At 204–215 days of age the MAM offspring were confirmed to be micrencephalic, a known effect of this drug at this dose and exposure period. On all tests of activity the MAM offspring were markedly hyperactive. The female progeny also exhibited a pronounced impairment of normal activity habituation patterns. The MAM males, however, showed a marked impairment of passive avoidance performance, while the females did not. At 2 months of age the MAM offspring also showed a pronounced deficit in learning a water maze. This maze deficit had not abated when tested again at 6 months of age. The MAM induced brain and behavioral abnormalities provide a potentially useful animal model of congenital micrencephaly and associated mental retardation.

Effects of neonatal destruction of the medial forebrain bundle in the cat: Long-term disturbances in learning ability, response to amphetamine challenge, and reactivity to auditory stimuli

These experiments ascertain some of the long-term behavioral effects of neonatal medial forebrain bundle (MFB) lesions in the cat. Bilateral electrolytic lesions ( N = 27) were made when the animals were 11 to 22 days of age. The long-term behavioral development of cats with these lesions were compared with that of a group of intact littermates ( N = 37) and a group of littermates that received lesions that did not encroach upon the MFB. When the animals were 18 to 40 days of age they were tested in a spatial discrimination. Animals with bilateral MFB lesions were capable of learning the discrimination but made more repeated errors than animals in the other groups. This effect was compensated for with additional training. When tested on a visual discrimination at 3 to 4 months of age, kittens with MFB lesions learned the discrimination in a normal manner. When the discrimination cues were reversed, however, they responded more frequently to the previously reinforced cue. The effects of d-amphetamine were assessed when animals were 7 to 12 months of age. Animals with bilateral MFB lesions displayed less frequent and intense head movement stereotypies and more locomotor responses to amphetamine than animals in other groups. The reactivity to a series of auditory stimuli was assessed when the animals were 1 to 2 years of age. Neonatal MFB lesions produced an impaired pattern of habituation of reactivity to auditory stimuli. Cats with these lesions responded normally to the initial presentations of the vocalizations. However, 24 h later they responded to the stimuli more vigorously than animals in the other groups. Taken together the results of this experiment and the previous report indicate that some effects of neonatal MFB damage were qualitatively different from those of lesions inflicted in mature animals and that a complex interaction among a number of factors was probably responsible for these differences.

Adolescents with cancer: Hypnosis for the reduction of the acute pain and anxiety associated with medical procedures

Eighteen adolescents with cancer were trained in hypnosis to ameliorate the discomfort and anxiety associated with bone marrow aspirations, lumbar punctures, and chemotherapeutic injections. Two patients rejected hypnosis. The remaining 16 adolescents achieved significant reductions in multiple measures of distress after hypnosis training. Preintervention data showed no pattern of spontaneous remission or habituation, and, in fact, an increasing anticipatory anxiety was observed before hypnotic treatment. Group reductions in pain and anxiety were significant at levels ranging from p less than 0.02 to p less than 0.002 (two-tailed t-tests). Significant reductions were also found in Trait Anxiety. A non-significant trend toward greater self-esteem was present. The predicted changes in the Locus of Control and General Illness Impact were not found. Comparisons between hypnosis rejectors and successful users unusually showed higher levels of pretreatment anxiety in the former. The pragmatic nature of hypnosis as part of comprehensive medical care in oncology is noted.

Fetal habituation in high-risk pregnancies.

Habituation is a basic form of learning and probably requires an intact central nervous system. Habituation in the behavioural response to vibration in 40 normal human fetuses was compared with that in a group of high-risk pregnancies with an increased risk of fetal neurological damage. Highly significant differences in habituation patterns between the high-risk groups and normal control subjects were found. This test may offer a method of assessing the integrity of the fetal central nervous system.

Patterns of habituation to electrical stimulation of reticular and auditory pathways

Patterns of habituation of the orienting response to electrical stimulation of midbrain, thalamus, and cortical components of the primary auditory pathway and the ascending reticular system were studied in awake, freely mobile cats. Individual orienting responses to high-frequency stimulation of structures in the auditory pathway could not be distinguished from orienting responses to stimulation of reticular structures. However, with repeated presentations of the stimulus, the orienting response to auditory pathway stimulation habituated significantly faster than did the orienting response to stimulation of structures in the ascending reticular system. Within the auditory pathway, orienting to stimulation of the inferior colliculus, the medial geniculate body, or primary auditory cortex did not result in distinguishable patterns of habituation. Stimulation of parietal cortex resulted in habituation that occurred significantly slower than habituation to auditory cortex stimulation, and significantly faster than habituation to stimulation of the midbrain reticular formation or the centre median nucleus of the thalamus. These results are discussed with regard to a hypothetical arousal system that includes the brain stem reticular formation, the intralaminar nuclei of the thalamus, and parts of the parietal cortex.

Untersuchungen zum Aktivierungs- und Habituationsverhalten hirntraumatisch geschädigter Kinder und Jugendlicher unterschiedlichen Schweregrades

The aim of this study was to analyse the pattern of activation and habituation of youngsters with head injuries depending on the injury's gravity. Nine patients were examined with decerebration after an apallic syndrome; the control group contained ten patients with slight cerebral contusion. The complex test stimulus (optical and acoustical stimulation requiring a reaction) was a phase of a daily, continuous 4-min load with the 'Wiener Determinationsgerät' (Schuhfried). The frequency of heartbeat was registered for 4 (8) days. We analysed the physiological and psychosubjective estimation as well as the psychophysical level of measuring to obtain concrete steps for rehabilitation, depending on the possible interactions. All variables demonstrated a definite distinction between the two groups of patients. Analysis of heartbeat frequency showed that, in spite of similar initial levels of activity, 'initial sensitization' appeared only in the control group; it diminished with habituation and repetition of the stimulus. The descriptive analysis of the HR development in the form of a mathematical exponential function showed that there were three relatively consistent types of reaction: sensitization, habituation, and indifference (nonresponder). The habituation reaction was found only in the control group, indifference only in the group of apallic patients. The analysis of reciprocal action of different levels of measurings shows a certain disorder in the functional systems of the apallic patients, as described by Luria (1976). After the test stimulus the sensomotor and physiological systems do not interact optimally in comparison with patients with slight head injuries. The resulting steps for rehabilitation are discussed.

Patterns of habituation to electrical stimulation of cerebral cortex in the awake cat

Patterns of habituation to electrical stimulation of cerebral cortex in the awake cat

A Possible Link between Intelligence Level and Habituation of the GSR

An attempt was made to correlate the intelligence level of three well-defined groups (Gifted, IQ 140; Normal, 95 IQ 105: Mentally retarded, 45 IQ 55) and the habituation rate and pattern of a GSR response to a series of light stimuli. The results indicate that the gifted and normal groups yield systematic patterns of GSR responding in contrast to the mentally retarded, whose distribution of GSR response pattern differs. The mentally retarded seem to yeild a larger number of ill-defined, non-systematic GSR responses. These results indicate a possible link between the measured level of intelligence by IQ test and the habituation pattern in an autonomic nervous system response.

Individual Differences in the Pattern of Habituation at 5 and 10 Months of Age.

Individual Differences in the Pattern of Habituation at 5 and 10 Months of Age.

Individual Differences in the Pattern of Habituation at 5 and 10 Months of Age.

Individual Differences in the Pattern of Habituation at 5 and 10 Months of Age.

Effects of differential interference with postnatal cerebellar neurogenesis on motor performance, activity level, and maze learning of rats: a developmental study.

The region of the cerebellum was X-irradiated in infant rats with selected exposure schedules designed to produce animals in which the cerebellar cortex was (a) essentially normal except for agenesis of late forming granule cells with axons situated in the uppermost molecular layer (12--15X), (b) lacking in stellate cells, with a severe reduction in granule cells with axons in the upper molecular layer (8--15X), (c) morphologically disorganized but had only intermediate cell agenesis (4--5X), or (d) disorganized and devoid of practically all postnatally forming interneurons (4--15X). In the first two experiments young adults had to traverse rotating rods that differed in texture and types of obstacles. The 8--15X animals showed no deficits on any of the rods tested. The third study dealt with spontaneous motor performance in the open field at three ages. The 4--5X and 4--15X animals were hypoactive as infants and young adults; this was attributed to their motor deficits. The 8--15X and 12--15X animals were hyperactive in the open field as young adults. The fourth experiment examined intra- and/or intersession habituation. No group differences were found in habituation patterns. In the fifth experiment, using activity wheels, the 4--15X group was hypoactive, and the 8--15X and 12--15X groups were hyperactive as young adults. In the sixth experiment young adults were tested for learning performance in a multiple-unit water maze. The 4--15X group was deficient on single alternation; the 4--5X and 12--15X groups on double alternation. The seventh experiment shed some light on the single alternation deficit of the 4--15X group; only these animals failed to alternate spontaneously in a nonaversive situation. In conclusion, these behavioral results, combined with those of recent morphological investigations, suggest that the cerebellar cortex is hierarchically organized: The basal domain of Purkinje cells and the lower molecular layer are implicated in the coordination of movements; the apical domain of Purkinje cells and the upper molecular layer, in the coordination of actions.

Effects of locally applied dopamine to the nucleus accumbens on the motor activity of normal rats and following alpha-methyltyrosine or reserpine.

The motor activity of rats was investigated following bilateral application of various doses (0--80 micrograms) of dopamine to the nucleus accumbens. A high dose (80 micrograms) of dopamine increased the motor activity of normal as well as alpha-methyltyrosine- and reserpine-treated rats. It also increased the late motor activity (6--9 min) of normal rats, probably due to stimulation of postsynaptic dopamine receptors. Lower doses (10--40 micrograms) of dopamine suppressed initial (0--3 min) motor activity of normal rats, perhaps due to stimulation of dopamine autoreceptors on the dopamine nerve terminals in the nucleus accumbens with a subsequent inhibition of dopamine neurotransmission. An intermediate dose (40 micrograms) of dopamine was able to restore the motor activity of alpha-methyltyrosine-treated but not of reserpine-treated rats at all time intervals. This difference, indicating a restoration of the normal pattern of habituation by dopamine only in animals pretreated with alpha-methyltyrosine, suggests that normal behaviour is dependent on release of dopamine by nerve impulses.

Tonic physiological responses to repeated presentations of phobic stimuli

Questionnaire, electrodermal and cardiac responses to phobic and neutral stimuli were assessed both within and across three daily test sessions. Each session consisted of 5 phobic and 5 neutral trials. Questionnaire responses in the first session showed some initial sensitization followed by habituation across the rest of the sessions. Cardiac response patterns differentiated phobic and neutral stimuli in the first two sessions. Electrodermal spontaneous fluctuation levels and habituation patterns differentiated the two stimulus types. Skin conductance levels showed sensitization across phobic trials and habituated across sessions, but showed habituation or asymptotic response levels to the neutral stimulus. The experiment raises methodological points suggesting that conflicting and unexpected results in the literature may be due to the use of phasic instead of tonic physiological responses and the use of stimuli which are not subject-specific. Results are also discussed in relation to proposals that psychiatric patients are those who are unable to cope with repeated life stresses.

The ontogeny of exploration in the rat: habituation and effects of handling.

Exploration, measured by head-dipping in a holeboard, was tested in male rats at 16, 21, 28, 56, and 84 days of age. Head-dipping increased with increasing age from Day 16 to Day 84, and so did the number of rears made. At all ages handled rats showed more head-dipping and made more rears than did their unhandled litter-mates. The age differences in exploration cannot be explained by different patterns of habituation: rats showed significant within-session habituation of head-dipping at all ages tested (Days 16, 21, and 28). Day 16 rats also showed significant between-session habituation.

The role of undernutrition in animal models of hyperactivity

The influence of neonatal growth retardation on subsequent spontaneous activity and activity following d-amphetamine (10 mg/kg, i.p.) was studied in CD-1 mice. Different growth rates were obtained by raising mice in litters of either 8 or 16 sucklings per lactating dam. The testing protocol was specifically designed to duplicate a procedure used to assess the influence of neonatal lead exposure on locomotor activity. At 35 to 37 days of age mice were individually tested for general locomotor activity and drug response. Developmental growth retardation influenced their pattern of habituation to the test apparatus and their locomotor response to emphetamine. It was concluded that growth retardation may partially account for behavioral effects previously attributed to the neurotoxic effects of viruses, 6-hydroxydopamine or inorganic lead.

Habituation of subjective anxiety during flooding in imagery

Patterns of habituation of subjective anxiety during flooding in fantasy are delineated for eleven obsessive-compulsive and six agoraphobic patients. The majority showed a curvilinear pattern of subjective anxiety response, while three patients showed a linear decelerating pattern. Habituation was found both within and across sessions. The results are compared with habituation patterns in physiological responses during flooding in fantasy and in vivo.

The Effect of Mild Illness on Habituation in the First Year of Life

To determine the effect of mild acute illness on habituation in the first year of life, 14 infants were repeatedly tested when well and when ill. Comparison of habituation patterns to visual and visual-plus-auditory stimulation revealed only minor performance differences between well and ill infants. However, further analyses on a subgroup of 7 infants demonstrated a number of disruptive effects associated with febrile illness. These effects were interpreted as hypersensitivity to stimulation resulting in fatigue and disruption of habituation patterns. Tentative practical implications of these findings are that infants continue to profit from environmental stimulation during acute afebrile illness, but that infants with acute febrile illness should be stimulated only for brief periods.

Habituation of fear: effects of intensity and stimulus order.

ABSTRACTThis study investigated snake‐fearful subjects' skin conductance, heart rate, and fear ratings to repeated presentations of seascape and snake films (10–13 sec duration). The films sampled three levels of fear intensity and were displayed in ascending, descending, or nonsystematic orders; additional Ss viewed only high‐fear material. A linear relationship with fear intensity emerged for fear ratings, but not for physiological measures. Differences found between orders in patterns of habituation were concordant for cardiac rate and fear ratings; relative to the other orders, the ascending sequence habituated less and displayed sensitization to material of higher fear levels. In all orders, there was marked habituation of physiological responses, especially in the first session. The possible role of adaptation level and implications of the data for desensitization and flooding were noted.

Complexity Levels, Habituation, and Individual Differences in Early Infancy

GREENBERG, DAVID J.; O'DONNELL, WILLIAM J.; and CRAWFORD, DONALD. Complexity Levels, Habituation, and Individual Differences in Early Infancy. CHILD DEVELOPMENT, 1973, 44, 569-574. To demonstrate a relationship between rate of habituation and complexity levels, 51 11-week-old infants were each given a rate-of-habituation test and a complexity-level test. As predicted, those infants who habituated rapidly (rapidly decreased their looking time to a single repeated stimulus in the habituation test) looked longer at the more complex patterns in the complexity test. The majority of infants with irregular habituation patterns resembled the slow habituators in terms of level of complexity preferred while the remaining irregular habituators appeared to respond randomly to both attentional tests.

Habituation to disturbance in the fiddler crab ( Uca annulipes) in its natural environment

Crabs of both sexes and of various sizes were subjected to a standardized test of ten consecutive disturbances in their natural habitat. Males and females reacted alike: 53 per cent became fully habituated within less than ten disturbances, and a further 12 per cent showed slower habituation. The remainder of the test individuals showed various other patterns of reactions. Reaction pattern and efficiency of habituation are size- (or age-) dependent, and they are modifiable by social interaction and by tide-determined activity phases. The structure and species composition (with regard to ocipodid crabs only) of the Uca habitat is considered briefly, and some observations on display and ‘rapping’ or drumming behaviour are reported.