Changes In Spontaneous Behavior Research Articles

Boltzmann-like and Boltzmann-Fokker-Planck equations as a foundation of behavioral models

It is shown that the Boltzmann-like equations allow the formulation of a very general model for behavioral changes. This model takes into account spontaneous (or externally induced) behavioral changes and behavioral changes by pair interactions. As most important social pair interactions, imitative and avoidance processes are distinguished. The resulting model turns out to include as special cases many theoretical concepts of the social sciences. A Kramers-Moyal expansion of the Boltzmann-like equations leads to the Boltzmann- Fokker-Planck equations, which allows the introduction of “social forces” and “social fields”. A social field reflects the influence of the public opinion, social norms and trends on behavioural changes. It is not only given by external factors (the environment) but also by the interactions of the individuals. Variations of the individual behavior are taken into account by diffusion coefficients.

Changes in spontaneous behavior in the dog following oral administration of L-deprenyl

An open-field activity test was developed for studying the effect of a single oral dose (range of 0.1–5 mg/kg) of L-deprenyl on spontaneous behavior in the dog. A computer program was used to quantify observations of locomotor activity, directed sniffing, urination, grooming, inactivity, jumping, rearing, and vocalization during a 10-min baseline and posttreatment session. Three dose-dependent behavioral changes were observed: an overall decrease in directed sniffing, an increase in total locomotor activity in females, and a decrease in frequency of urination in males. These effects were only seen at the dose levels of 2 mg/kg or higher. Computer-assisted tracings of behavioral patterns showed increased stereotypical behavior and decreased exploratory behavior at the high-dose levels. These behavioral effects are most likely due to either increased levels of phenylethylamine resulting from inhibition of monoamine oxidase B and/or production of amphetamines as a result of the metabolism of L-deprenyl.

Sodium arsanilate-induced vestibular dysfunction in meadow voles ( Microtus pennsylvanicus): effects on posture, spontaneous locomotor activity and swimming behavior

Vestibular dysfunction was chemically induced in male meadow voles (Microtus pennsylvanicus) by intratympanic injections (30 mg per side) of sodium arsanilate (atoxyl). The control group received intratympanic injections of isotonic saline. After a one-week recovery period the voles were behaviorally assayed for integrity of their labyrinthine systems. All subjects were tested for the presence of the air-righting reflex and body rotation-induced nystagmus. Three weeks later a multivariate assessment of spontaneous motor activity of the voles was carried out in the automated Digiscan Activity Monitor. In addition, the swimming behavior of the voles was examined. Voles with vestibular dysfunction exhibited pronounced postural abnormalities (head dorsiflexion), were not able to swim with their nose above the water for a 1 min test period, and displayed disorientation and thrashing movements. In the Digiscan activity test the atoxyl-treated voles displayed significantly more activity in the horizontal measures (Ps less than 0.01), including greater distance travelled per movement and greater speed of movements, relative to the control animals. The labyrinthectomized group also spent significantly (P less than 0.05) less time in vertical movements and exhibited significantly more time in stereotypic behavior (P less than 0.01), relative to controls. Atoxyl-treated voles also showed significantly less thigmotaxis (wall-hugging) than the control animals (P less than 0.01). In general, changes in spontaneous behavior observed in the sodium arsanilate-treated voles were consistent with the presence of postural and balance abnormalities and a redirecting of exploratory vertical movements toward horizontal locomotion to the extent that these animals were clearly hyperactive in this dimension. The multivariate behavioral assessment available in the Digiscan Activity Monitoring system, thus seems to be especially useful in the examination of behavioral components affected by vestibular dysfunction.

Age-related changes in spontaneous behavior and learning in NMRI mice from middle to old age

Spontaneous behavior, sensorimotor reflexes and learning of 3-, 11-, 17- and 22-month-old virgin female NMRI mice were compared. Sensorimotor abilities decreased significantly from the age of 17 months in proportion to the muscular and equilibrium demand of the test. Open-field activity, hole board exploration as well as activity in the Y maze and plus maze decreased from the age of 11 months. However, in the open-field and Y maze, it was not possible to distinguish between 11-, 17- and 22-month-old mice, whereas in the plus maze, activity was drastically decreased in 17- and 22-month-old mice. In the plus maze, indices of fear-motivated behavior suggest a greater sensitivity to the situation in the age groups of 17 and 22 months. Spontaneous alternation also decreased from the age of 11 months, but at the age of 22 months, a rotational behavior emerged. Spatial learning was markedly impaired from middle age, i.e., 11 months, as indicated by longer latencies and absence of spatial bias in place learning. In cued learning, the 11- and 17-month groups eventually reached the level of the 3-month-old mice, while the 22-month age group remained impaired. Changes in swimming ability or speed did not appear to account for the swimming maze deficits. In contrast, a sensory or perceptual deficit cannot be excluded for the oldest mice. Discriminant and correlational studies performed on intraindividual scores showed that for the majority of the tasks, aged mice did not exhibit similar degrees of impairment across the behavioral variables and that for a given chronological age, the degree of impairment is heterogeneous. The results are discussed in relation to a similar preceding study testing 3-, 6-, 9- and 12-month-old mice.

A statistical test to assess changes in spontaneous behavior of rats observed with a computer pattern recognition system.

A computer pattern recognition system, RAPID, has been used to study the spontaneous motor activity of Sprague-Dawley rats. This system produces a large number of measures of the activity of control and experimental groups in any given study. The large number of measures involved presents a problem when one attempts to decide whether the behavioral activity of the exposed group differs from that of the control group. Extensive Monte Carlo studies have been performed in an attempt to develop and validate a simple statistic to be used in such decisions.

No change in spontaneous behavior of rats after acute oral doses of aspartame, phenylalanine, and tyrosine

Spontaneous behavior subsequent to acute oral administration of high doses of aspartame, phenylalanine, or tyrosine was analyzed using a computer pattern recognition system. Sprague-Dawley male rats (250–300 g) were dosed orally with aspartame (500 or 1000 mg/kg), phenylalanine (281 or 562 mg/kg), or tyrosine (309 or 618 mg/kg), and their behavior was analyzed 1 hr after dosing. The computer pattern recognition system recorded and classified 13 different behavioral acts performed by the animals during the first 15-min exploration of a novel environment. Three measures that provide independent information concerning motor output from the central nervous system were taken: the number of behavioral initiations, total time, and time structure. These results were compared with the effects induced by d-amphetamine. Plasma concentrations of phenylalanine and tyrosine were determined from blood samples taken immediately after behavioral examination. Data analysis revealed that these doses of aspartame, phenylalanine, and tyrosine did not induce any significant changes in spontaneous behavior. Unlike low doses of amphetamine and despite high plasma concentrations of phenylalanine and tyrosine, no behavioral alteration was detected by the computer pattern recognition system. Absence of behavioral changes in this study using an objective analysis of behavior ralses questions concerning the relationship between amino acid precursor loading and purported anecdotal changes in behavior following aspartame administration.

Neonatal exposure to 3,3′,4,4′-tetrachlorobiphenyl: changes in spontaneous behaviour and cholinergic muscarinic receptors in the adult mouse

We have previously reported that 3,3′,4,4′-tetrachlorobiphenyl (TCB) affects muscarinic cholinergic receptors (MAChR) in the neonatal mouse brain when given to suckling mice at the age of 10 days. As shown in the present study, such early exposure to TCB may also lead to a permanent change in the MAChR and disturbed behaviour of the mice as adults. Male NMRI mice were given two single oral doses of TCB, 0.41 or 41 mg/kg body wt, and a 20% fat emulsion vehicle (10 ml)/kg body wt. The behavioural test at adult age of 4 months indicated a significant change in spontaneous motor behaviour in the TCB-treated mice. In mice receiving the highest dose of TCB there was also a minor increase (5%), although significant, in the density of MAChR in the hippocampus, assayed by using the tritium-labeled muscarinic antagonist, quinuclidinyl benzilate ([ 3H]QNB). As previously reported, this part of the brain was affected in the neonatal mouse, which shows that the cholinergic system during rapid development in the neonatal mouse brain is sensitive to disturbance. This may lead to permanent changes in the animals as adults, accompanied by behavioural changes.

No Change in Spontaneous Behavior of Rats after Acute Oral Doses of Aspartame, Phenylalanine, and Tyrosine

No Change in Spontaneous Behavior of Rats after Acute Oral Doses of Aspartame, Phenylalanine and Tyrosine. MULLENIX, P. J., TASSINARI, M. S., SCHUNIOR, A., AND KERNAN, W. J. (1991). Fundam. Appl. Toxicol. 16, 495–505. Spontaneous behavior subsequent to acute oral administration of high doses of aspartame, phenylalanine, or tyrosine was analyzed using a computer pattern recognition system. Sprague-Dawley male rats (250–300 g) were dosed orally with aspartame (500 or 1000 mg/kg), phenylalanine (281 or 562 mg/kg), or tyrosine (309 or 618 mg/kg), and their behavior was analyzed 1 hr after dosing. The computer pattern recognition system recorded and classified 13 different behavioral acts performed by the animals during the first 15-min exploration of a novel environment. Three measures that provide independent information concerning motor output from the central nervous system were taken: the number of behavioral initiations, total time, and time structure. These results were compared with the effects induced by d-amphetamine. Plasma concentrations of phenylalanine and tyrosine were determined from blood samples taken immediately after behavioral examination. Data analysis revealed that these doses of aspartame, phenylalanine, and tyrosine did not induce any significant changes in spontaneous behavior. Unlike low doses of amphetamine and despite high plasma concentrations of phenylalanine and tyrosine, no behavioral alteration was detected by the computer pattern recognition system. Absence of behavioral changes in this study using an objective analysis of behavior raises questions concerning the relationship between amino acid precursor loading and purported anecdotal changes in behavior following aspartame administration.

Sodium arsanilate-induced vestibular dysfunction in rats: Effects on open-field behavior and spontaneous activity in the automated digiscan monitoring system

Vestibular dysfunction was chemically induced in Long-Evans rats by intratympanic injections (30 mg per side) of sodium arsanilate (atoxyl). Following a one-week recovery period the rats were behaviorally assayed for integrity of the labyrinthine systems. All subjects were tested for presence of the air-righting reflex, the contact-righting reflex (by lightly holding a sheet of Plexiglas against the soles of the rat's feet), and body rotation-induced nystagmus. All animals were then tested for their ability to remain on a small (15 × 15 cm) platform. Next, the subjects were given two 10-min open-field tests during which ambulation, rearing, grooming, and defecation responses were recorded. Four to five weeks later all rats were tested twice (60 min per session) in the automated Digiscan Activity Monitor which provides a multivariate assessment of spontaneous motor activity. The rats with vestibular dysfunction (Group VNX) took significantly less time to fall off the platform ( p<0.01). They also exhibited significantly more open-field ambulation but fewer rearing responses ( ps<0.01). An examination of group correlation coefficients for open-field variables and the platform test scores revealed some interesting group differences ( ps<0.05). In the Digiscan tests the atoxyl-treated rats exhibited fewer number of horizontal movements, but increased speed for these movements ( ps<0.05). Vertical movements did not differ significantly in incidence, but these movements were greatly reduced in duration ( p<0.001). In general, changes in spontaneous behavior observed in the sodium arsanilate-treated rats were consistent with a loss in ability to balance on the two hind feet (during rearing or grooming) and a redirecting of exploratory vertical movement sequences toward horizontal locomotion, especially in the open-field test. The multivariate behavioral assessment available in the Digiscan Activity Monitoring system seems to be especially useful in the examination of behavioral components affected by vestibular dysfunction.

Age-related changes in spontaneous behavior and learning in NMRI mice from maturity to middle age

Spontaneous behavior and learning and memory of 3-, 6-, 9- and 12-month-old virgin female NMRI mice were compared. Open field activity and spontaneous alternation in a Y-maze decreased in an age-related manner, reaching a statistical level of significance for the groups aged 9 and 12 months. Spatial learning was highly impaired in 9- and 12-month-old mice in the place version of a Morris-type water maze but not in the cued version of this task. Changes in motor activity, swimming ability or speed did not appear to account for these deficits. In a one-trial passive avoidance, performance was more variable, although a deficit in the oldest age group was clearly evident using a cutoff time of 120 sec. The passive avoidance was not attributable to reduced shock sensitivity. Together, these results suggest that the onset of aging in NMRI mice occurs at the age of 9 and particularly 12 months. NMRI mice of this age could, therefore, represent a viable animal model for the study of cognitive impairments in aging.

Salt appetite is suppressed by interference with angiotensin II and aldosterone.

Blockade of central but not peripheral mineralocorticoid receptors, with the antimineralocorticoid RU-28318, reduces but does not suppress salt appetite aroused by sodium depletion in the rat. When central mineralocorticoid blockade is combined with captopril treatment to prevent formation of endogenous angiotensin II the appetite is completely suppressed. Suppression of the appetite occurred without changes in the animals' spontaneous ingestive behaviors, sodium excretion, or insulin-induced food intake. These results demonstrate that a synergy of angiotensin II and aldosterone is responsible for the expression of depletion-induced salt appetite in the rat.

Altered neurobiological responses to acute immobilization in social-isolated mice

Social isolation results in dynamic changes of neurobiological functions. The altered internal state of the CNS is reflected in changes in spontaneous behavior, changed responses to transmission-related substances and charged responsiveness to an additional impairment of normal relations between the organism and its environment. We analysed the influence of an acute 2-hour immobilization on such isolation-dependent changes. Whereas the susceptibility to pentetrazole-induced seizures increased continuously with lengthening of isolation and was not affected by the additional impairment, the responsiveness to transmission-related substances changed dynamically depending upon isolation-induced alterations. An immobilizatio-induced increase in responsiveness to LSD and propranolol was demonstrable in grouped controls and after short-term isolation. The apomorphine stimulation during prolonged isolation experienced a down- and an upregulation which were repeated in a stronger manner by immobilization responses especially after long-term isolation. It is suggested that the dynamics of isolation-induced changes coincided with changed acute adaptive functions.

Relationship of changes in spontaneous motor activity to spontaneous circling in rats with unilateral 6-hydroxydopamine lesions of the substantia nigra

Two unilateral injections of 6-hydroxydopamine into the substantia nigra and ventral tegmental area of adult rats pretreated with desmethylimipramine produced severe unilateral depletions of limbic and striatal dopamine. These animals sustained global deficits in spontaneous motor activity with no recovery evident from 1 to 14 weeks postoperative. The frequency of spontaneous circling increased during the 1 st few weeks postoperative and then remained stable during the last 2 months of observation. The changes in circling were independent of changes in global spontaneous motor behaviors. Biochemical determinations indicated an increased dopamine turnover in residual limbic and striatal dopamine neurons but with substantially changed dihydroxyphenylacetic acid:homovanillic acid ratios. The absence of functional recovery of both normal and asymmetric motoric behavior indicates that severe uncompensated deficits in motoric function produced by unilateral 6-hydroxydopamine lesions can provide a useful animal model for the study of dopaminergic contributions to movement disorders.

Spontaneous fetal behavior after maternal exposure to ethanol

Acute and chronic intubations of ethanol to pregnant rats produced changes in spontaneous fetal behavior four hours later. Fetuses from mothers in intermediate alcohol groups (4 and 6 g/kg) were substantially less active than controls (0 g/kg), but fetuses from low (2 g/kg) and high (8 g/kg) alcohol groups showed little indication of behavioral suppression. Circulating levels of alcohol in maternal blood, fetal homogenate and amniotic fluid at the time fetuses were observed confirmed that fetuses were exposed to alcohol in utero, but the measured concentrations of alcohol were not predictive of fetal activity. We suggest that some of the developmental consequences of Fetal Alcohol Syndrome may be the consequence of fetal inactivity induced by alcohol in utero.

Differentiation of basal ganglia dopaminergic involvement in behavior after hippocampectomy

Large bilateral aspiration lesions of the hippocampus in rats lead to a variety of changes in spontaneous behavior measured in an open field/hole board, relative to sham and neocortically lesioned controls. These changes include increased locomotion, and decreased grooming frequency and rearing bout duration. When animals were injected with the dopamine (DA) agonist 3,4-dihydroxyphenylamino-2-imidazoline (DPI: 0.5, 1.0 and 5.0 μg) into the nucleus accumbens one week after surgery, the behavior of hippocampally lesioned rats was restored to levels not different from control lesioned rats. Haloperidol injections (0.05, 0.1 and 0.5 μg) into the caudate nucleus were not able to do this. Further, DPI injected into the caudate nucleus one month after surgery was also able to attenuate some of the effects of hippocampal damage. On the other hand, haloperidol injections into the nucleus accumbens did not influence behavior. The results are interpreted in terms of hippocampal lesion-induced alteration of a balance in basal ganglia DA systems, indicated by modified response to pharmacological intervention and which mediate the behavioral effects of the lesion.

Assessment of functional alterations in rats exposed prenatally to five central nervous system depressants (4). Behavioral responses

The effects of prenatal treatment of central acting drugs on the functional development of the CNS of the offspring were examined for changes in spontaneous behavior and those induced by the administration of diazepam (2mg/kg, i.p.) at 5-6 weeks of age or apomorphine (0.3 mg/kg, s.c) at 3 months of age. Pregnant Wistar-Imamichi rats were injected s.c. with haloperidol (H),0.1 mg/kg; imipramine (I), 5 mg/kg; nitrazepam (N).

Reduction of ECS-induced retrograde amnesia of passive avoidance conditioning after 5,7-dihydroxytryptamine median raphe nucleus lesion in the rat.

5,7-Dihydroxytryptamine (5,7-DHT), median raphe nucleus (MRN)-lesioned and sham-lesioned rats were submitted to one-trial passive avoidance conditioning followed by electroconvulsive shock (ECS) or sham-ECS. On test session (24 h later) MRN-lesioned rats presented a longer conditioned response and, chiefly, a remarkable reduction of ECS-induced retrograde amnesia in comparison to sham-lesioned animals. This effect appeared unrelated to major changes in spontaneous behavior: on training session MRN-lesioned rats exhibited a faster stepping-down from the platform; their exploratory activity into a novel cage was characterized by a slightly higher initial response; moreover MRN lesion did not significantly effect pain threshold. A reduced brain 5-HT functional activity following MRN lesion was suggested by the study of the hyperactivity syndrome induced by tranylcypromine plus L-tryptophan. Lastly, MRN-lesioned rats showed a significantly lower brain 5-HT steady level without differing from the sham-lesioned ones with respect to turnover rate. The reduction of ECS-induced retrograde amnesia observed in 5,7-DHT, MRN-lesioned rats was considered as due to a lower synaptic availability of 5-HT at the time of ECS administration.

Infradian cycles in dormice (Glis glis)

Infradian cycles of body weight occur in captive dormice,Glis glis. The period of these cycles is often about 2 months but is highly variable both between and within individuals. These cycles can persist for at least 3 years. This paper describes a number of variables that change on an infradian basis along with body weight. These include: food and water intake, weight of the liver, adrenal and salivary gland weight, testes weight and spermatogenic condition, body temperature and wheel-running activity. Both the amount of running and its distribution over a 24 h period change. However, infradian cycles do not appear to be generated by the circadian system because they persist even in continuous bright light sufficiently intense to disrupt circadian organization. They also persist in LD 18∶6, LD 12∶12, LD 6∶18 and in naturally changing photoperiods. No evidence of photoperiodic effects on cycles was detected except that animals in long days have slightly higher moulting scores than those in short days. Moulting is more marked when body weight stays relatively stable. In dormice remaining stable in weight for several months testes have sperm present. The period of infradian cycles is temperature dependent: in a cool room animals that hibernate have longer cycles with periods varying from a few months to about a year. In a number of respects at least, infradian cycles appear to be accelerated circannual cycles. The adaptive value of a system that gives rise to infradian cycles probably relates to opportunism in an unpredictable environment. Infradian cycles in dormice may be a useful preparation for obtaining data on spontaneous physiological and behavioural changes in hibernators in less than a year.

Neurohypophyseal hormones and behavior: Effects of intracerebroventricularly injected hormone analogs in mice

Neurohypophyseal hormones evoke spontaneous behavioral changes in mice. This study compares the potency of four naturally occuring neurohypophyseal hormones and of ten analogs with amino acid residue replacements selected in such a manner as to cover each residue position of the hormones with the exception of the cystine residue. Peptides were administered intraventricularly and the sum of foraging, scratching and squeaking, recorded at 30 second intervals during a 30 min session, was measured as a function of peptide dose. The most potent group of peptides is represented by the neurohypophyseal hormones as well as the five analogs [Hly 8] vasopressin, [Δ 3-Pro 7]AVP, [Thi 3]LVP, [Abu 4]AVP and [Abu 4]LVP. [Leu 4]LVP showed significant activity but was far less potent than the natural hormones. None of the remaining analogs enhanced activity with an increase in peptide dose. This group included both peptides with C-terminal modifications and those in which the tyrosine (position 2) or the asparagine residue (position 5) of the hormones were substituted by alanine. The neurohypophyseal hormone-induced behavioral results of this study reveal a structure-function relationship, which is in its most important conclusions, identical to the conformation-activity model proposed for endocrine activities of neurohypophyseal peptides.

Recovery of spontaneous alternation following lesions of the entorhinal cortex in adult rats: Possible correlation to axon sprouting

Adult rats with unilateral or bilateral lesions of the entorhinal cortex were tested over time for changes in spontaneous alternation behavior. Rats with bilateral lesions did not display spontaneous alternation throughout the duration of the study. This suggests that the entorhinal area plays an important role in the manifestation of spontaneous alternation. In contrast to rats with bilateral lesions, those with unilateral lesions displayed recovery to preoperative levels of alternation within 10 days after surgery. It is suggested that the circuitry changes accompanying axon sprouting after unilateral lesions may participate in the recovery of spontaneous alternation.