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Standard tests of murine unconditioned anxiety such as the elevated plus-maze and light-dark test are based on a dichotomy of avoidance behaviour (walled vs. open arms and dark vs. light compartments). We combined the principles of both tests by modifying the elevated plus-maze as follows: one walled arm was made transparent and had a white floor (WTW), whereas the other walled arm was opaque-gray having a black floor (WOB). Furthermore, one open arm had a white floor (OW), while the other had a black one (OB). These modifications allow the distinction between more than two sub-compartments that elicit different degrees of avoidance behaviour, thus having a higher discriminative potency. Additionally, the paradigm was thought to permit the within-task detection of pharmacological side effects on the perception of the anxiogenic stimuli provided. The degree of avoidance of the sub-compartments exhibited by saline-treated mice for the distal parts of the four arms was distributed as follows: WOBWTW=OBOW. This pattern demonstrates that the sub-compartments elicited at least three differed degrees of fear in control mice, and that these were able to discriminate between bright/dark compartments WOB vs. WTW and OB vs. OW. Diazepam given at 1, 2, and 3 mg/kg doses increased the number of entries into the distal part of the most aversive open white arm and increased the total time spent on the undivided open white arm. Both the 2 and 3 mg/kg dose increased motor activity and impaired bright/dark discrimination for the open but not for the walled arms. Thus, the graded anxiety test might be useful to screen for substances that retain the normal perception of anxiogenic stimuli, but prevent the transact of fear into undue panic reactions.

A common problem with underground facilities for public use is the feeling of danger and entrapment they generate. This article discusses these reactions in light of modern behavioural theory explaining the development of phobic reactions. According to this view, the majority of phobic reactions are a result of two factors: A biological preparedness to avoid certain stimuli, and a learning episode strengthening the avoidance behaviour. A third factor, degree of perceived control, has important modulating effects on phobic reactions. A biological preparedness to avoid situations characterised by a limited possibility for escape can explain some aspects of the seemingly universal negative associations that underground space evokes. Some of the consequences that this theory has for design of underground facilities for public use are discussed.

The present study was conducted to investigate the influence of parental modelling on the acquisition of fear and avoidance towards novel, fear-relevant stimuli in a sample of 30 toddlers. The toddlers were shown a rubber snake and spider, which were alternately paired with either negative or positive facial expressions by their mothers. Both stimuli were presented again after a 1- and a 10-min delay, while mothers maintained a neutral expression. The children showed greater fear expressions and avoidance of the stimuli following negative reactions from their mothers. This was true for both genders although the degree of modelled avoidance was greater in girls than in boys. The strong observational learning results are consistent with views that modelling constitutes a mechanism by which fear may be acquired early in life.

For ecotoxicological assessments of contaminated or remediated soils pointing to the habitat function of soils for biocenoses, standardized tests with earthworms (acute test, reproduction test) are available among others. Tests used for routine applications should be sensitive and indicate impacts on test organisms after short test periods. The usually applied earthworm tests do not satisfactorily fulfil these criteria. Therefore, in the present work, a behavioural test with earthworms (test criterion: avoidance) was investigated in detail using uncontaminated, artificially contaminated and originally contaminated soils. It was demonstrated that the avoidance behaviour is primarily determined by pollutants, and not by chemical-physical soil properties. The sensitivity of the presented test reaches the sensitivity of established tests. For waste sites, a considerably higher sensitivity was determined. An avoidance behaviour of at least 80 per cent of the worms leaving the soil to be assessed is proposed as a criterion for toxicity.

If a helpless newborn infant does not form an attachment to its care-giver, even an abusive one, its chances of survival diminish, so evolution should strongly favour attachment by the infant, regardless of the quality of care-giving(1). As a part of the brain called the amygdala is critical for learned fear in adult animals(2, 3, 4), we investigated whether the development of learned avoidance behaviour could be delayed by late maturation of amygdala function. We found that very young rat pups exposed to various odours associated with shock treatment learn an approach response to that odour, whereas older pups learn odour avoidance. We show that the origin and development of learned odour-avoidance behaviour is associated with enhanced neural responses in the amygdala during odour-shock conditioning.

1. Water fleas (Daphnia magna) bred at 23°C were non-responsive to temperatures between 13 and 25°C. 2. At the lower (11°C) and upper limits (30°C) their klinokinetic avoidance behaviour showed a larger intraindividual than interindividual variation. 3. Thermal sensitivity for avoidance responses in D. magna was about 1.5°C. 4. For D. magna bred for one parthenogenetic generation at 14°C heat avoidance temperature was about 8°C lower, and cold avoidance temperature was about 1°C higher than in D. magna from 23°C. 5. In group experiments the animals showed some preference for the acclimation temperature. 6. Cold induced stenothermy and warm induced eurythermy in D. magna were related to the mode of reproduction.

Chemical signals from conspecifics can influence the behaviour and neuroendocrine axis of mice. Several different molecules are excreted with urine, depending on hormonal level, and can indicate the sex of the emitter. In male mice, these chemicals are the major urinary proteins (MUPs) and some small volatile odorant molecues that are found bound to them. We tested adult males for light avoidance behaviour in a two-chamber apparatus, with one light and one dark side, in the presence or absence of male urinary substances. The presence of chemical cues on either side of the cage was expected to modify light avoidance behaviour. The volatiles released from purified MUPs had the same effect as whole adult male urine, in that they induced a faster onset of exploration of the light compartment. The results show that mice can use the information carried by the odorant molecules released by MUPs to recognize the urine of male mice, and respond appropriately. Copyright 1999 The Association for the Study of Animal Behaviour.

This paper proposes that the phenomenon of anticipatory nausea and/or vomiting is a component of a phobic response to chemotherapy. Two cases are presented to highlight the clinical aspects of chemotherapy phobia. The evidence confirming such a diagnosis is put forth as it relates to anticipatory anxiety, phobic response, avoidance behaviour and treatment.

Other marine mammals tend to avoid walruses. The present paper describes two incidents of avoidance behaviour displayed by ringed seals in the presence of a walrus.

Many phenomena of short term adaptations of the CNS have been explained with changes in the conductance of ion channels, that are induced by cascades of second transmitter systems ultimately leading towards ion channel phosphorylation. On the other hand, it is the long-term consolidation of memory that appears to be vulnerable, in particular in the context of age-related disseases of which Alzheimer’s is but the most prominent example. A few years ago, cell adhesion molecules were considered just sticky agglutinants, but now it is well accepted that they are accurately regulated glycoproteins involved in li- gand-receptor relationships triggering intracellular second messenger cascades. They are known to guide axonal growth and the migration of neurectodermal cells during epige- netic differentiation. Also during CNS regeneration cell adhesion molecules are involved.

A mode! is presented for understanding crises that are so intense that we can say that the organization itself is in crisis. After a review of the literature by type, the examination of three cases shows that three different phenomena cause such crises: a phenomenon of "avoidance" that structures the organization, a situation-dependent event that forces the organization to face avoided problems, and a management not adapted to this confrontation. Practical lessons are drawn in conclusion., Cet article présente un modèle pour comprendre les crises qui affectent une organisation à tel point que l'on peut dire que l'organisation elle-même se trouve être en crise. Après une revue différenciée de la littérature, trois cas sont examinés. Ils font ressortir que de telles crises sont causées par trois phénomènes de nature différente : un phénomène d'évitement structurant l'organisation, un événement conjoncturel qui oblige l'organisation à faire face aux problèmes évités et une gestion inadaptée de ce face-à-face. Des enseignements pour la pratique sont tirés en conclusion.

Many species, from bacteria to vertebrates, have been reported to use the geomagnetic field as a major cue for oriented short and long range migration [1–10], but the molecular nature of the underlying receptor has remained elusive. One of the main reasons may be that past attempts to train animals to respond to magnetic stimuli proved surprisingly difficult [11]. We present a novel approach to magnetic conditioning, using a fast, fully automated assay system relying on negative reinforcement. Weak electric impulses were applied to punish fish that failed to escape upon magnetic field alterations (avoidance behaviour). Using this assay we first demonstrate magnetosensation in Mozambique tilapia, a fish migrating regularly between freshwater and the sea. Next we wondered whether non-migratory fish have a magnetic sense, such as zebrafish, the genetic fish model organism. Zebrafish were trained in groups of 4 individuals, and statistically highly significant reactions to magnetic field changes were recorded. The demonstration of magnetosensation in zebrafish opens a possibility to genetically identify the magnetoreceptor and its downstream signalling cascade.

The quality of human contact that hens are exposed to will determine the degree of fear of humans that they experience. This has consequences for the welfare of commercial laying hens, as hens that are afraid of humans will be regularly exposed to a fear-provoking stressor. Hens can be habituated to human presence using positive or neutral human–animal interactions, although the specific human behaviours that are considered positive or neutral by the hens are still being determined. This experiment investigated whether the proximity or duration of visual contact with a human affected fear of humans in commercial caged laying hens (n = 216). Commercial laying hens were exposed to daily visual human contact at one of three proximities (0, 0.75 or 1.50 m) and one of three durations (2, 30 or 90 s) in a 3 by 3 factorial design for a period of 28 days. Avoidance behaviour was assessed on Days –5, 15 and 30, and the plasma corticosterone response to handling was assessed on Days –5 and Day 30. Visual contact with a stationary human at close proximity (0 m) significantly (P = 0.03) reduced the avoidance response of commercial laying hens to an approaching human, although there was no clear effect of proximity on corticosterone response to handling. The duration of human contact had no effect on avoidance behaviour or corticosterone response. Stockpeople may consider working more closely to the cages in a non-threatening manner to reduce fear of humans in their flock.

The chick archistriatum has been implicated in avoidance learning and filial imprinting. However, its role in these learning paradigms may be due to the inhibition of normal avoidance responses, since the avian archistriatum has been shown to play a role in fear/avoidance behaviour. The involvement of the archistriatum in the expression of unlearned fear/avoidance behaviour was therefore investigated in two day-old chicks. Chicks were exposed individually to a novel 'open field' for 5 min. Behaviour was recorded on videotape for analysis. In a separate but concurrent experiment, bilateral archistriatal lesions, sham archistriatal lesions or lateral cerebral lesions were made in day-old chicks which were then exposed to the 'open field' arena. At the end of each exposure a novel object was dropped near the chick. Chicks with archistriatal lesions generally displayed greater movement, more pecking behaviour and spent more time near the centre of the 'open field' than other chicks. There were no differences between the treatment groups in latencies to move or begin peeping. The behaviour of untreated chicks in the 'open field' was similar to that of sham-lesioned chicks and there was no effect of hatch on behaviour. Upon exposure to a novel object, indices of fear and avoidance were not changed in lesioned chicks. These results demonstrate that in the young chick, the archistriatum may be involved in the response to mild or intermediate levels of environment or isolation-related stress, but does not appear to be important for overt fear responses or avoidance of novel objects. Taken together with the results of previous work, the data suggests that the archistriatum may be directly involved in avoidance learning and imprinting.

Human interactions, particularly negative ones, affect the behaviour and physiology of laying hens, with possible implications for bird productivity and welfare. The present experiment investigated the effects of handling on the behaviour and plasma corticosterone concentrations of laying hens. A 2 × 2 × 3 factorial design was used to study the following three main effects: human contact during rearing [an additional 12 min of human contact per day (AC) or no additional contact (MC) during rearing]; handling quality in adulthood [brief daily exposure to positive (+ve) or negative (–ve) visual contact with a human]; and handling proximity in adulthood [handling-quality treatment (+ve or –ve) imposed at the following three distances from the birds: Near, 0–45 cm; Middle, 45–75 cm, or Far, 75–105 cm]. AC during rearing resulted in reduced avoidance behaviour of humans during adulthood, whereas handling imposed at the Far level resulted in greater avoidance behaviour than did handling at the Near or Middle level. The quality of the handling (+ve or –ve) had little effect on avoidance behaviour; however, there was a trend (P = 0.07) for hens receiving +ve handling to have a lower corticosterone response to human contact than those receiving –ve handling. These results demonstrate that visual human contact can influence the avoidance behaviour of laying hens.

Groups of C57BL/6 mice were injected intraperitoneally with GM1 monosialoganglioside at different ages during development and subsequently tested for the retention of an inhibitory avoidance task 24 h after training. Results show improvements in inhibitory avoidance retention according to the age of the animals, the doses of GM1 used and the length of treatment. The effective doses ranged from 20 mg/kg for all age groups after 7 days treatment to 280 mg/kg for 6- and 7-week old animals after pre-trial treatment. Six- and 7-week-old mice are more sensitive to GM1 treatment than 5-week-old animals and, with decreasing lengths of treatment, increasing doses of GM1 are needed to improve the performance of the animals. These findings show that short treatment durations can be effective in improving inhibitory avoidance retention as long as the doses of GM1 administered are increased and that animals are more sensitive to the treatment when they are 6 or 7 weeks of age than when they are 5 weeks old.

An examination has been made of factors triggering attack behaviour in adult Cephalota circumdata leonschaeferi (Cassola), living in the coastal strip of the Orbetello Lagoon Nature Reserve. Coloured dummies (blue, white, brown, black, red, and green) of various sizes (3.8, 7.5, 15 and 30 mm) have been used to evaluate the role of the following stimuli: movement, size and colour. Attacks recorded with experiments carried out in absence of movement (3.83%) were markedly fewer than those in presence (57.26%) of movement. The size of bait most frequently attacked by Tiger beetles was the 7.5-mm long one (corresponding to 1/2 the size of the adult Cephalota). The largest bait (30 mm) was significantly less stimulating than the other three sizes. Red was the colour that most stimulated attack and white the least. Brown and black gave results more similar to those of red, whereas green and blue frequently displayed a significantly less stimulatory effect. The two sexes displayed differences of reaction to the b...

An American Elk calf (Cervus elaphus) that was captured near human habitation in Jasper National Park, Alberta, was fitted with a radio-collar and released 40 km away in the park's main valley of the Athabasca River. The calf joined a local herd of elk, and its radio signal revealed that the elk, in two months' time, travelled eight times back and forth between the herd's traditional semi-open winter range at Devona and a largely wooded area at Rocky River >3 km away. Each time, on their trans-valley route the elk crossed a busy highway, a railway, and a partly frozen river. Sightings of elk and Wolves (Canis lupus) were inversely correlated on 97 days of observation at Devona. We conclude that the elk's migrations were prompted by their urge to avoid and flee from Wolves, which were common at both locations.

An observation of a female Mallard (Anas platyrhynchos) avoiding unpaired drakes, in breeding season, until reuniting with her mate after audio recognition of the rähb call. This observation supports the supposition that this vocalization by the male Mallard is a response to separation from the female and functions as a contact call in mate recognition.

1. Interneurones 501 and 504 are identified sound-sensitive interneurones in the pterothoracic ganglion of the noctuid moth Noctua pronuba (Fig. 1). Both neurones receive monosynaptic input from the A1 afferent (Figs. 2, 3) and experiments with current injection suggest that the synapse is chemical (Fig. 4). The EPSPs evoked in either IN 501 or 504 by the A1 afferent do not facilitate (Fig. 5A, B). 2. Temporal integration in INs 501 and 504 was compared by presenting the moth with tones at repetition rates found in the search, approach and terminal phases of the echolocating call of a hunting bat (Figs. 6, 7, 8, 9). INs 501 and 504 differ in their capacity to resolve stimulus repetition rates because the mean decay times of their compound EPSPs differ by a factor of three (Fig. 10), although both interneurones receive monosynaptic input from the A1 afferent. 3. The features extracted from the authentic, prerecorded, call of an echolocating bat at the level of the pterothoracic ganglion were examined by recording sequentially from a range of interneurones in the same preparation (Fig. 11). The capacity of INs 501 and 504 to encode the various phases of the call was examined in the light of their measured mean decay times and related to the avoidance behaviour of the insect (Figs. 12, 13).

Brain-injured patients may frequently develop behaviour disorders in order to avoid participating in rehabilitation activities. In recent years, the use of behaviour modification techniques, particularly the use of positive reinforcement and time-out, has been increasingly reported in the literature as a means of remediating behaviour disturbance in this population. However, reward- or extinction-based programmes are generally not effective in the treatment of avoidance behaviours as they may be ineffective or, at worst, encourage further avoidance of rehabilitation activities. This paper, describes the use of satiation through negative practice in the successful treatment of a severely brain-injured patient whose behaviour, in the form of prolonged shouting, had previously not responded to the range of behavioural techniques used previously with this population. Two successive treatment programmes that were used in an attempt to satiate shouting are presented. Significant reductions in both the frequency and duration of shouting were found, enabling physical and functional gains to be made through successful participation in previously avoided rehabilitation activities. The validity of the use of this technique in the treatment of avoidance behaviour in brain-injured patients is discussed.

How conditioned opiate withdrawal gives rise to avoidance behaviour was examined using a defensive burying procedure in rats made dependent with a morphine pellet. The subjects underwent withdrawal precipitated by naloxone (0.1 mg/kg, SC) on two or three occasions in a box containing only a small object. When exposed to the object in the presence of sawdust one or more days later, the subjects avoided contact and buried this object, i.e., pushed and piled the sawdust against it. The behaviour was seen only when withdrawal had been paired with the object, which was the case even with a choice of objects on the test. Approach but no burying was seen in nondependent animals when the object was paired with 1 mg/kg morphine. Burying, therefore, was concluded to be a defensive response elicited in rats by an object specifically paired with precipitated opiate withdrawal. Consideration of burying and other defensive responses reported to be elicited by cues of withdrawal (conditioned place and taste aversion, and suppression), with respect to the behavioural demands of these responses and the test conditions needed to see them, suggested that a goal of avoidance may be a primary event encoded in a withdrawal cue, as is known for predictors of nonpharmacological noxious events (e.g., shock).

The symptoms so coolly described in textbooks seem very different when you see their effects in real life. ‘Avoidance’ is one of the classic symptoms of post-traumatic stress disorder (PTSD). As well as suffering nightmares, flashbacks, personality changes and depression, suffers will try to avoid contacts or situations which cause them to relive their traumatic experience. We have learned this can include locations, sights, sounds, odours, uniforms and people with similar names or appearance to those involved.

1. Methods of analysing the spatial patterns of birds are reviewed. Few methods have sought to explain an observed spatial pattern in terms of the behavioural responses between conspecifics. The spacing of oystercatchers, Haematopus ostralegus L., feeding on a mussel bed is investigated using a model of one possible response. 2. The model assumes that each individual avoids all other individuals within a certain distance, the hard-core radius, and has no interaction with other individuals beyond this distance. 3. The positions of the oystercatchers are obtained from a set of photographs. Each photograph is transformed to a plan view, and the resulting set of plan views is assembled to give the spatial pattern of birds on the mussel bed. The observed spatial pattern is summarized by means of the distribution of nearest-neighbour distances. 4. The behaviour of the birds is modelled by placing non-overlapping particles of a given radius within the region of the mussel bed occupied by the birds. The distribution of nearest-neighbour distances for the particles is obtained by simulation. The best-fitting particle radius is that which minimizes the residual error between the observed and simulated distributions of nearest-neighbour distances. 5. Statistical analyses show that avoidance behaviour, as measured by the best-fitting particle radius, decreases during the low-water period. We interpret this result in terms of the changing value of a food item to an individual through time.

1. Approximately 65% of grey plovers at the Zwartkops estuary, South Africa, defended feeding territories throughout the austral summer. Territories were established during the arrival period (September), once the foraging densities of grey plovers exceeded 4.6 birds ha -1 . Territories ranged in size from 490 to 2800 m 2 . 2. Average territory size decreased over the season and was significantly and inversely related to the total number of grey plovers on the estuary, rather than to resource patterns. Individual variation in territory size was inversely related to resource density. 3. Territorial encounter frequency decreased from September to March, probably due to neighbour familiarity, and was also reduced by avoidance behaviour. The frequency of aggressive encounters was significantly higher for owners of smaller territories. 4. The owners of large territories spent significantly more time foraging during the low tide period than did owners of small territories. However, energy intake rates were negatively correlated with territory size, with the result that the total low tide intake was approximately equal, irrespective of territory size. 5. Non-territorial grey plovers foraged at higher densities than territorial birds. These birds achieved a decreasing proportion of the energy intake rate of territorial birds over the season, and may have had to depart later on northward migration.

A calf's previous experience may be expected to influence its subsequent response to acute stress. In the present study, the effects of the social environment on the response to transport have been investigated. Direct behavioural observations of all competitive interactions were recorded for 40 h in a group of 18 3-month-old Friesian male calves reared in an intensive barley beef system. Butts, head-to-head battles, approach and avoidance behaviour and displacement of one calf from the trough by another were noted. The interactions of each calf with all 17 others were scored in a matrix according to wins and losses. Calves were then ranked according to the mean proportion of wins and clear social order was found at this point in development of the group. At 14 weeks of age, these calves were transported in a trailer in two groups of nine animals, for a distance of 4 miles. Blood samples were taken for cortisol analysis before and after transport. All calves showed a significant increase in cortisol levels in response to handling and transport. Calves which won least in social interactions had the highest basal cortisol levels and showed the greatest cortisol response following handling and transport. Calves winning most showed the smallest cortisol response to the procedure. These results suggest that a calf's response to handling and transport can be affected by its position in the social order. Changes in stereotypies associated with tethering of dairy cows I. Redbo Department of A nimal Nutrition and Management, Swedish University of Agricultural Sciences, Kungsangen Research Farm, S-753 23, Uppsala, Sweden

Ten Boran ( Bos indicus ) cows were studied over 64 oestrous cycles. Alterations in sexual behaviour and of the ovaries palpated per rectum were related to the plasma progesterone profiles detemined using an extracted double antibody radioimmunoassay. The mean cycle length in the cows was 23 ± 0 · 4 days. Oestrus detection efficiency using standing to be mounted, was 27 percent. Restlessness, where observed, reliably indicated that a cow was in the period of basal progesterone concentration. Mounting, sniffing, head-butting, being sniffed, being mounted with avoidance behaviour, although shown by 50 percent of cows during the basal progesterone period were not confined solely to this part of the cycle. Use of Kamar heat-mount detectors in conjunction with standing to be mounted identified 44 percent of oestrous animals. However, the occurrence of false positives during the rest of the cycle precluded their use as sole indicators of oestrus. Accuracy of palpation of corpora lutea was 61 percent during periods of elevated and 98 percent in periods of basal progesterone concentrations.

Chlordiazepoxide, imipramine, and amitriptyline, given alone or in combination, were tested in mice subjected to 5 daily 100-trial avoidance sessions in the shuttle-box. When the drugs were given alone, chlordiazepoxide and the lower doses of imipramine facilitated avoidance behaviour. The higher doses of the two antidepressants impaired avoidance behaviour. Mixtures of chlordiazepoxide and imipramine produced some facilitating effects, while depressant effects prevailed in the chlordiazepoxide-amitriptyline combinations.