ELSEVIER Applied Animal Behaviour Science 52 (1997) 275-289

b APPLIED ANIMAL BEHAVIOUR

P SCIENCE

The treatment of phobias in the dog

Robin Walker, John Fisher, Peter Neville Institute of Applied Pet Ethology, c/o Gables Veterinary Group, 78 Bromyard Road. Worcester WR2 5DA.

UK

Abstract

Since 1992 the authors have been compiling a casebook of detailed histories of canine phobia. As the work progressed modifications were made to the diagnostic criteria of anxiety in the dog. A combination of phenobarbitone with propranolol has been employed with perceived success supported by anecdotal evidence from the owners, behaviorists and veterinarians involved. An attempt is made here to set out a rational system of diagnosis with regard to published work on the neuropsychology of fear. Tentative suggestions as to the efficacy of the treatment and interpreta- tion of results are made. It is hoped that such an appraisal might be the ground work for compilation of suitable protocols for more rigorous assessment of such cases. 0 1997 Elsevier Science B.V.

Ke?;words: Emotion; Reward; Relief; Frustration; Phenobarbitone; Propranolol: Dog

1. Introduction

Classification of behaviour is necessary to structure a discussion, but classification itself can be made tiresomely complex. It must not be treated as ‘science’ as slavish adherence to a list leads to compartmentalised diagnosis and to treatment by rote. Three and a half centuries ago, Hobbes (1651) gave us his classification of Endeavour (motivation to live) by either Appetite or Aversion. We might now use the terms Motivation to Survive using a mixture of Approach and Avoidance behaviours in order to acquire food and to reproduce without being killed. This division of behaviour would mirror the concept that individuals are either Reactive or Non-reactive in accordance with much of the work on the genetics of fear.

The work of Rolls (1990) suggests that we might categorize emotional states as Rewarded, Punished, Frustrated or Relieved. The merit of this method of classification lies in facilitation of medication choice with regard to the neurendocrinology of the emotional state. since problems arise from misdiagnosis of a dog’s mood and motivation and are compounded by inappropriate medication (Fig. 1).

016%1591/97/$17.00 0 1997 Elsevier Science B.V. All rights reserved PII SO168-1591(96)01128-8

276 R. Walker et al. /Applied Animal Behauiour Science 52 (1997) 275-289

Positive reinforcer (Reward)

+

Ecstasy

- - Elation Positive reinforcer (Reward)

- - Pleasure

stops or is ormtted Rage

Negative Anger Frustmtion Relief reinforcer

4 I I (punishment) I I I I

*stops or is omitted

Grief Sadness -- Apprehension

Fear

Terror

Negative reinforcer (punishment)

Fig. 1. Reinforcement contingencies. Some of the emotions associated with different reinforcement contingen- cies are indicated. Intensity increases away from the centre. It is worth noting that if the subject can respond actively to the omission of a positive reinforcer, anger might follow. If only passive behaviour is possible, sadness or depression might occur. After Rolls, 1990.

To describe or predict the tactics of responding we need to use a construct such as the ‘four Fs’ to describe fear behaviours or strategies: Freeze, Flight, Flirt and Fight (Marks, 1987a).Freeze: immobility. This is of two types, (a) attentive (if I keep still I might not be seen!); and (b) tonic (if I sham death utterly convincingly he/she/it might lose interest!). Flight: withdrawal, escape, avoidance. Flirt: Deflection of attack and ap- peasement (submission). Fight: Aggressive defence (includes attack when emotional and in defence of status, or young).

Marks (1987a) defined fearfulness as a trait. He demonstrated that nervous strains of rats and dogs have been bred and that fearfulness can be inherited. In studies of nervous rats, Pointers and Labradors, fearfulness can be shown to have been inherited. By handling and sressing newborn rats and mice, changes in neuroreceptors and cortisone receptors in the brain have been produced resulting in less fearful and stressful adults demonstrating that the formed emotional brain ventures into the environment and only then begins to learn by experience as a child learns from its parents. Indeed the flavour of personality - extroversion vs. introversion - is best demonstrated by considering these characteristics in humans. There, extroverts are considered less fearful and less susceptible to punishment. They condition best to rewards and not well to punishments. Introverts, on the other hand, tend to condition rather better under threat of punishment.

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Application of this to animals would suggest that one would expect relatively poor results in training extrovert dogs by aversive methods, and that the extrovert’s response to anti-anxiety drugs is likely to be zero at anxiolytic dose levels. The introverted dog, on the other hand, will appear fearful, timid, suspicious, submissive and aggressive on a scale of intensifying symptoms and will respond on a corresponding scale to the same dose of anxiolytic, all of which is a familiar sight in a veterinary clinic.

In the diagnosis and treatment of phobias, classification of fear should be kept simple and reflect what is known of the neurophysiology of the emotional defence systems, although there is as yet no formal classification of dog and cat fears comparable with the DSM IV (the Diagnostic and Statistical Manual of Mental Disorders, Volume IV. American Sociology Association, 1994).

Anxiety is seen as a state of alarm without necessarily any obvious cause. The mode is one of continual arousal, movement is tentative, restless or indecisive.

Panic is the state when arousal evokes a full emotional (autonomic nervous) response.

Phobia is the term used for fear of some specific thing which may increase in intensity over many years or gain full force immediately as a panic.

This learning of fear can occur by the mechanisms of classical conditioning. An anxious animal may learn phobic reactions to any number of conditional stimuli such as noise. Gray (1990) suggests the existence of brain systems for emotion and cognition from neurobiological studies of animals. These overlapping systems comprise a behav- ioral approach, fight/flight and a behavioral inhibition system (Fig. 2).

This analysis of anxiety would appear to form a rationale for the commonly observed results of both medication and training. For example anxiolytic drugs will oppose the inhibition of ongoing behavior, increased arousal and increased vigilance and will not reduce the results of actual punishment, frustration or induced panic. This theory is covered by Gray (1987) in his book The Psychology of Fear and Stress.

The interplay between these systems explains how, under conditions of danger, both freezing and fight/flight patterns may be intensified at the same time and alternate rapidly with each other. It therefore cannot be over-emphasized that the application of punishing training methods, or a threatening or unpredictable home environment can cause both systems to conflict with potentially disastrous results.

Signals of punishment ~ 1 Bebwiounl I Behaviourai Inhibition

Signals of non-reward -

Novel Stimuli 1 =p ~hmmthhd ~

Innate Fear Stimuli

t

1 IW ~ IncressedAttention

_.~___. Anti-Anxiety Drugs

Fig. 2. The behavioral inhibition system (BE) as defined by its inputs and outputs. After Gray (1987)

278 R. Walker et al. /Applied Animal Behauiour Science 52 (19971275-289

2. Phobia

Simple or monosymptomatic phobias are simple examples of passive avoidance behaviour. These are the normal fears of the quite brave. We all tend to like the trees and cosy caves of our ancestors; solitude and wide empty spaces can engender unease while public gatherings may trouble us because they may portend trouble. Agoraphobia is most common and destructive among humans.

In dogs we have the same picture. Natural puppy fears inborn are perpetuated into adult life, with the devastating phobia of separation; the unendurable loss of the pack while at the same time being trapped. This is the canine equivalent of agoraphobia (people filled space fear). Both are extremely difficult to treat and both tend to entail extreme panic. Here the personality type is again of great importance. The anxious or neurotic dog will pass into panic while the isolated extrovert may respond with noisy frustration and rage with a psychopathic disregard for pain.

The physiology of the panic is the same however induced. Differentiation may be by way of personality assessment and drug response into Simple Phobia, Anxiety with multiple phobias and Separation Phobia (or Frenzy). This leads to a number of methods with which to approach fear - the basis of behaviour therapy.

1. Toughening up. Simple repeated exposure to the aversive stimulus. 2. Pavlovian Counter-conditioning. The aversive stimulus is used as a conditional stimulus for appetitive unconditional response. 3. Instrumental counter-conditioning. In which the aversive stimulus comes to act as a discriminative stimulus for the performance of a rewarded instrumental response. In practical therapy, the most important process is that of exposure or toughening,

albeit combined with some associative process. Two of the more widely used methods are systematic desensitization and flooding or implosive therapy.

Systematic desensitization aims at brief exposures to the minimized stimulus which terminate if fear is shown. The exposure should be followed by deep relaxation using techniques in which the patient is trained. The exposure is graded in intensity over a period of time. The level of anxiety is kept down so that counter-conditioning is facilitated. The teaching of relaxation presents difficulties but grooming and massage techniques imaginatively applied offer hope. The relaxation and general restraint of anxiety levels can be greatly assisted by the use of anti-anxiety drugs in a manner which does not block perception of what is going on or actively hinder the nervous mecha- nisms of reward and memory storage.

In flooding therapy, the patient is exposed in full measure to the aversive stimulus and any attempt to escape or avoid is opposed, an approach unpopular with therapists lacking the requisite steely nerves or stony hearts. The act of flooding causes an immediate increase in fear levels which lead to hasty abandonment of the enterprise (viz. shooting over gundogs in place; standing on the lead of thunder phobic dogs as they attempt to flee).

The closest approximation to flooding that we have employed is that of repeated forcible handling of fear aggressive dogs. Hospitalization and repeated restraint and dressing of ears and wounds will regularly result in a patient who submits and joyfully greets its nurses on subsequent occasions.

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At this moment, it is believed that a combination of drug and behaviour therapy is highly successful. While it is clear that drug therapy cannot solve problems by itself, behaviour therapy can. solve a great number of problems. Drug therapy in the short term can create the circumstances which make the behaviour therapy possible.

Attempts to organise the arrival and duration of fear inducing stimuli constitute behaviour therapy. The environment itself will provide many such stimuli in a haphazard manner. Exposure is going to happen anyway and therefore toughening will occur by chance. There is a high spontaneous rate of recovery from anxiety symptoms in humans, (nearly 70% in 2 years).

The most responsive cases are the anxiety trait individuals who are afraid of almost anything. Reduce the anxiety and the environment is full of everything needed in the way of stimuli for exposure. The infrequent stimuli (thunder in a British summer, annual Guy Fawkes fireworks) pose the greatest difficulties.

3. The benzodiazepine receptor

This creates a ‘damping’ effect which only occurs when brain neurones begin to fire excessively (a feed back effect). By definition the generation of anxiety is excessive nervous activity in particular systemsThere will be no effect unless the system in question is in action. The anti-anxiety drugs are ‘in waiting’ for overactivity, not numbing everything in sight whatever its function. Dose level is therefore important. A little wine is anxiolytic. Too much is anaesthetic. At the right dose a barbiturate has a precise effect on anxiety and epilepsy without necessarily causing marked sedation.

The benzodiazepine action is similar but not quite so precise, the anti-convulsive action is not so reliable. Benzodiazepines may affect memory functions. Injections have been shown to produce anterograde amnesia. The behaviourist is concerned that learning takes place. It is interesting that the most commonly cited examples of apparent interference with training (blockade) have been with librium (the benzodiazepine chlordiazepoxide). The animals in our series of trials of phenobarbitone and propranolol have emerged from treatment apparently with new behaviour patterns. Another impor- tant consideration is the effect of drugs on the reward or reinforcement systems. Drugs which block dopamine and noradrenalin effects may also block positive reinforcement effects with implications for counter-conditioning. The phenothiazines (acepromazine, chlorpromazine), butyrophenones (haloperidol, spyroperidol) and diphenyl- butylpiperidines (pimozidel have been proved to have this effect.

A mass of neuranatomical, neurochemical, neurophysiological and behavioural evi- dence has accrued which emphasises the part played by increased noradrenergic brain activity in the development of anxiety and panic. The prime centre for stimulating such arousal is the locus coeruleus (blue spot). The fear producing effects of the LC are reduced by numerous agents, notably morphine, benzodiazepine, tricyclic antidepres- sants and propranolol. Diazepam is the benzodiazepine most commonly used in the dog and cat. It is relatively quickly eliminated from the canine system and is consequently fairly ineffective compared with phenobarbitone. Cats are often given diazepam for the anxiety which induces them to urine mark their home territory. There may be less

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marking but if no attempt is made to deal with the cause of the anxiety the problem will usually return when the drug is withdrawn.

4. Rationale for the use of propranolol

Human heart patients on beta blocker treatment to prevent the heart from racing (tachycardia) often report a reduction of anxiety. This response is clearly due to a more central mechanism and it can be no coincidence that the septo-hippocampal system is aroused by ascending noradrenergic fibres from the LC and is richly supplied with beta-adrenoreceptors. The amygdaloid complex also has noradrenergic beta receptors.

A small cluster of cases have been treated with propranolol as the sole medication. It is found that dogs with anxiety about everything but nothing in particular, when placed on atenolol or propranolol, became calm. Acute fears, phobias and panic attacks did not respond sufficiently to permit long periods of assessmen, but we never used the drug in careful controlled exposure experiments. Dodman, 1994 reports the use of propranolol and pindolol (also a beta-blocker) in dogs. ‘The anxiety reducing effect is only mild (perhaps 30-50% improvement) but it is often enough to facilitate a desensitization program’.

The way in which a beta-blocker may ‘blunt’ the experience of an emotionally disturbing (‘flash-bulb’) event and thus mute its recall is explored in work by Cahill et al., 1994.

Phenobarbitone - is the drug of choice for epilepsy in dogs and has been used haphazardly for aggression, futilely for predation, too late for panic and ineffectively for frustration. Since we have discovered the difference between anxiety and punishment phenobarbitone has been used for its anxiolytic properties. The great doubt has been either that they learn anything whilst on medication, or that what they learn is dependent on the state of ‘being on it’. The impression has been that the dog does not learn not to be afraid. In combination with the beta-blocker propranolol a very different result is obtained. Phobias are apparently very effectively reduced by the combination and the dog can learn not to be afraid.

Tricyclic anti-depressants - The mode of action is still controversial but seems to be interference with the re-uptake of noradrenalin and serotonin thus increasing their availability. It may seem paradoxical that the tricyclics can effectively control panic attacks whilst raising noradrenalin levels which are implicated in generating anxiety. Serotonin is believed to be deficient in some violent criminals and potential suicides. The autonomic changes seen in panic resemble those seen in electrical stimulation of the central grey component of the fight/flight system. The serotonergic projection from the Behavioural Inhibition System to the central grey is inhibitory. Raising serotonin levels should enhance this. The side effects of the tricyclics include noradrenergic effects on the heart and human patients report anxious sensations.

5. Panic disorder and ‘sudden rage’

Panic attacks can be triggered in people by injections of lactic acid (a by-product of muscular activity) or by having them breathe air containing an elevated amount of

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carbon dioxide. PET scans of cerebral blood flow during panic attacks show the inputs and outputs of the septo-hippocampal system activated just prior to the attack and activity in the anterior poles of the temporal lobes during the attack. Panic attacks can resemble partial complex seizures with confusion and clouded consciousness. Patients with temporal lobe epilepsy report fear and anxiety prior to seizure. A snoring dog with a restricted airway can therefore become the subject of a panic attack.

6. A preliminary survey

By 1992 it was clear that many cases of anxiety and phobia in dogs were not responding to behavioural therapy alone. In order to gain more information the use of phenobarbitone in conjunction with propranolol was promoted among some of the constituent practices of the Association of Pet Behaviour Counsellors, a protocol for dosage was devised for the guidance of veterinarians and owners were encouraged to write lengthy accounts of their pets problems and to maintain diaries of progress whilst on medication and subsequent to drug withdrawal. The protocol was issued in the form of notes.

6.1. Propranolol and phenobarbitone as an adjunct to behaviour therapy

The use of propranolol and phenobarbitone in dog and cat veterinary medical practice is well established and documented. Propranolol has been used in veterinary cardiology and in the management of thyrotoxicosis. Phenobarbitone is still advanced as the drug of choice in the treatment of epilepsy. Both drugs have been employed in human medicine as anxiolytics and their relative usefulness and drawbacks recorded.

There has been much use of both drugs in the treatment of fears and anxiety in dogs by veterinary surgeons but very little reporting. The first author has been developing a case archive since August 1992 and it is hoped that this will reveal the usefulness of propranolol by itself and in conjunction with phenobarbitone.

Propranolol as a sole medicament will control general agitation as shown by tremor, diarrhoea (irritable bowel or intestinal ‘hurry’ syndrome) and ‘formless’ nervousness outdoors. General calming, weight gain, slower feeding and sleeping more have been reported.

The addition of phenobarbitone simultaneously seems to extend the anxiolytic control to specific phobias and situational fears. Fear of fireworks, thunder and high winds have been controlled to the great satisfaction of clients. In some cases the phobia has not occurred whilst on the medication and in others reduced to minor aversion such as pacing and retreating to bed. A frequent report is that the dog is more affectionate. A number of cases of aggression have responded well enough for behaviour therapy to be feasible.

The neuropsychology of anxiety is dauntingly complex, but in simplified terms it seems possible that the beta-blocker is acting on the arousal systems of the locus coeruleus, and the ascending noradrenergic pathways to the hippocampus.

Phenobarbitone acts at GABA receptor sites to facilitate inhibition of neurones concerned with the neurophysiology of behavioural inhibition and fight/flight be-

282 R. Walker et al/Applied Animal Behaviour Science 52 (1997) 275-289

haviour. The dog (or cat) tends to remain calm (but not sedated) and to approach rather than avoid in the fear modes of freezing, flight, deflection/appeasement or defensive aggression.

Bradycardia, hypotension, and heart failure are contra-indications for propranolol. In older dogs or toy breeds whining or confusion may occur. This year has seen publication of various dose regimes.

6.2. Methods: dose rates

Phenobarbitone: dogs 2-3 mg kg-’ oral b.i.d. Propranolol: Small dogs 5 mg or more t.i.d. Large dogs lo-20 mg t.i.d. or 2-4 mg kg-’ divided t.i.d. (e.g. 40 mg t.i.d. for 30 kg dog) ‘.

For ease of compliance in dosing the regime of Phenobarbitone 2-3 mg kg-’ b.i.d.; Propranolol 2-3 mg kg-’ b.i.d. has proved effective *.

Published data are heavily influenced by the experience of advanced and pharmaco- logically ‘aggressive’ treatment of severe cardiac conditions. These must be balanced by data from healthy behaviour cases.

Doses of 5 mg b.i.d. propranolol and 7.5 mg b.i.d. phenobarbitone are effective in the cat,

This treatment is not a substitute for behavioural modification. Controlled exposure or counter-conditioning should be carried out during treatment, in the withdrawal phase and afterwards.

Periods of treatment will vary from 3 months at a minimum up to six months where the stimulus for fear is presented infrequently (e.g. thunder phobia). For temporal lobe epilepsy cases with mixed aggression and fear permanent treatment must be considered.

Responsibility for the supervision of the treatment and the suitability of the animal in terms of health must reside with the referring veterinary surgeon.

7. Results

The following two case histories are representative of many received from be- haviourists.

7.1. Case History Number 1

Cross-breed, medium sized male dog, 18 months approx. Obtained about 7 weeks before first contacting me. In RSPCA kennels about 3 months. Tramp lives with retired couple. Previously owned by a woman who kept him chained all the time because he

’ Dodman, N., Tufts University, Department of Animal Behaviour. Personal communication, reported at WSAVA Congress 1993 by Lansberg, G.

* Walker, R.E., Unpublished APBC cases, 1992-1994.

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had a tendency to run away. No further details about his history except that he was taken by the RSPCA as a cruelty case.

21.2. 94 - Barking at other dogs then hiding behind owner’s legs. Cowers if owners yell at him. Springs at dogs then hides behind owner’s legs or holds onto owner’s arm. Barks and whines if sees other dogs, even at great distance. Gets excited when kids run past and when sees people in brightly coloured garments. Very affectionate to owners. Owner pulls on leash to try to control. The owner was obviously extremely fond of the dog and worried about him. He is very sensible and suffers from ‘nerves’ himself. We took Tramp out and I brought my collie, Lucy onto the scene at a distance while owner fed sausage as a distraction. He did not react fearfully although he did see me and my dog. The lead was kept slack and the introduction very short indeed. Usually Tramp would have gone into full panic just seeing the other dog. Owner was to repeat this as often as possible and to minimize the possibility of ‘accidents’, he was advised not to try letting Tramp meet other dogs ‘to see how he gets on with them’. Initially he thought this was a good idea because Tramp is okay with some dogs and attacks or backs off from others. Recommended Dog Training Discs for barking at people passing by through the window and chasing moving targets (notably joggers).

18. 3. 94 - Getting better with other dogs, occasionally panics, stamps feet on owner and pulls forward. Started to display fear at black bin-liners in trees, milk bottles rolling in the wind, ‘things’ appearing in the dark. Veterinarian prescribed Phenobarbi- tone/Propranolol.

7.4.94 - Phenobarbitone 15 mg, 1 tab twice daily, Propranolol 10 mg, 2 tabs twice daily - Little effect.

21.4.94 - Phenobarbitone 15 mg, 2 tabs twice daily, Propranolol 10 g, 3 tabs twice daily. Significantly reduced fear response. Very quiet for the first couple of days then back to normal self.

Arranged ten managed sessions with very pleasant introductions to other dogs. Cutting a very long story short, at the last session went for a walk (wearing Gentle Leader) with another dog. Very calm. Armed with discs to sound at any leaping and barking but no need. Owner wants to continue contact with the aim of actually bringing Tramp into a class situation. No facilities for this at the moment, but will be arranged. No significant aggressive fearful incidents for many months (14.11.94). Some residual ‘training’ problem (chasing rabbits and recall) which seems to give owner more pride in the dog than worry. Vet weaning off Propranolol, now 2 tabs twice a day in order to see which drug having major effect.

A further report dated 18.8.95 records excellent results. There has been no relapse into fearful behaviour since November 1994.

7.2. Case History Number 2

A typical history, embodying many of the most commonly reported features of a phobia, is that of the Labrador bitch, ‘Womble’, resident in the author’s practice. This dog was born in 1988. She was startled by a fireworks party in 1989. Her fear was compounded by her owner rushing after her in flight and comforting her in the room in

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which she hid. Over the next 4 years Womble acquired an annual reinforcement of the fireworks phobia on 5 November, and began to develop an array of extra fears, smoke alarms, fax machine beeps, crow scarers, children’s toy pistols and party poppers. By 1993 walks with the dog were spoiled by frantic attempts to dig her way underground to escape crow scarers. Finally she began to take flight from the premises on hearing sudden noises. She was treated with the phenobarbitone/propranolol combination. The fears subsided at once. In house the fax beeps elicited approach behaviour with much wagging and panting (flirting). The opportunity to counter condition with food rewards was taken. No human responses or recognitions of noises in the distance was allowed.

After some 6 months of therapy which covered a period including thunderstorms and fireworks, Womble was weaned off medication.

In the event of a loud thunder clap or on hearing certain sounds such as medical bleepers on the television, she quietly makes her way to a favourite settee and sits staring intently at the wall. She is ‘coping’ but no-one must fuss her at this point.

Scores of such histories with voluminous diaries and minutely detailed descriptions have yielded a number of highly predictable common features.

7.3. The importance of owner behaviour

The significance of the human response to startling sounds or events is repeatedly underlined in the anecdotes. Owners who have clutched their dogs, comforted them, fallen on top of them (when startled by low flying aircraft) repeatedly describe the onset of a lasting phobia in the dog. The extent to which the dog is influenced by human reactions of alarm or concern cannot be overemphasized and forms a crucial part of the behavioral therapy. These signals need not be gross. Subtle signs of apprehension by the owner can evoke responses by the dog. The ultimate expression of this acute sensitivity is to be seen in the ‘seizure alert’ dogs which are apparently able to detect signs of imminent seizure in their epileptic owners.

7.4. Increased affection

Dogs on the anxiolytic medication often become more affectionate and playful. This is generally appreciated, but may be reported as a failure or a nuisance by a few owners whose dog is untypically ‘clinging’ or constantly underfoot. Far from being undesirable, such a tendency must make reward based behaviour therapy much more likely to succeed.

7.5. State dependent learning

The notion that dogs are sedated or do not remember new behaviour patterns when medication ceases, is disposed of by the reports of dogs who learn simple tricks and new responses which are clearly well remembered post treatment. The sensitization of dogs to training discs by frustrative non-reward techniques proceeds easily in dogs on

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anxiolytic therapy. Their responses are in no way muted by therapy and are readily elicited post removal of the drugs.

7.6. Fear, temporal lobe epilepsy and the limbic system

Given that the condition of fear and epilepsy share a common transmitter complex and are associated with exactly the same areas of the brain, it can be no surprise that the two processes appear to overlap. This is not to say that one is the other but that it is indisputable that epileptics report anxiety, panic and anger. The survey SO far has revealed a syndrome in male dogs which may best be described as psychomotor seizure. Typical of this type of case is the Bull terrier ‘Burt’. The initial report is reproduced in full:-

The pattern of Burt’s behaviour is that described as episodic dyscontrol with features quite characteristic of psychomotor epilepsy or complex partial seizure. Complex partial seizures are epileptic seizures characterized by impairment but without total loss of consciousness. They may have a motor components which may be walking, stamping, jabbering, repeated vocalization (palilalia), tonic or clonic head movements. Autonomic symptoms may include pallor, flushing, vomiting, sweating, piloerection, pupil dilata- tion, borborygmia and incontinence. Affective or emotional signs can include fear, anger or rage. Epileptic anger is apparently unprovoked and abates rapidly. Dam, 1992 The aggressive outbursts (and fearful episodes) tend to be time-locked to re-entering the house after exercise and on rousing from sleep in the evening. The salient behaviours are unfocussed eyes, flushing, staring at walls and nodding, burying head in bushes or under curtains, growling for periods even when alone. Trance like behaviour and stereotypic gait (vividly described by the owner as moonwalking) can be induced by walking under low branches which brush the back. Significantly one episode occurred when Mrs. R.* * * was stroking the dog’s back. The pruritus which Burt suffers from has a rather ‘atopic’ look to it and may have significance in that it could deprive him of a measure of deep sleep which may lead to deep ‘catch-up’ snoozes with arousal problems as he struggles awake. The role of inflammatory mediators, such as histamine and arachidonic acid, in disturbing cerebral blood flow by vasomotor effects is not clear but I suspect significance will soon be discovered. Burt also snores thunderously and it is my view that hypercapnia can be as relevant in dogs (as it is in humans) as a trigger for panic arousal from sleep.

My suggestion has been to increase the phenobarbitone to a level more suitable for epileptic control at 2 to 3 mg/kg. in line with the work of Dodman et al., 1992. I have started withdrawal of the propranolol for the time being on the off chance that it may inadvertently increase seizure activity as described by Bolwig et al., 1992. For a contrary view see Jaeger et al., 1979. As Burt clearly does not recognise his owners when he is afflicted I have sensitized him to training discs by conditioning frustration with titbits. He responded well to this and when Mr. R.* * * has repeated the procedure the discs will possibly provide a means of focusing Burt’s attention when he starts to ‘go off’. Burt’s owners are (understandably) quite afraid of his unpredictable behaviour, but it is important (albeit difficult) not to react to the growling which may in part have become a

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learned strategy for manipulating the humans. Burt growls very convincingly when he wants his toy for example.

This type of case responds very well to anticonvulsant levels of phenobarbitone medication. The response to standard behavioral protocols designed for so-called ‘dominance’ or ‘fear aggression’ cases will be disappointing.

7.7. Frustration

One very clear result of using phenobarbitone and propranolol for cases described as ‘separation anxiety’ was the discovery that two quite distinct types of behaviour are expressed under this title. A dog that is anxious about being alone may have a variety of cues for fearful behaviour. The response to anxiolytic medication is very good without any other procedures except avoiding heavy signalling of impending solitude or human responses to the behaviour which reinforce its significance. A dog that is frustrated or angry that its owners have departed will not (by definition) respond in the least to such medication. Such a dog must be trained rigorously that,on occasions, it is alone and not rewarded by any interaction when ‘time-out’ is clearly signalled even though humans are present. Judicious use of serotonin reuptake inhibitors such as fluoxetine have proved especially helpful in facilitating such procedures. Given the difficulty of deciding the emotion underlying behaviours whose expression is similar or identical, the use of phenobarbitone and propranolol can be diagnostic in these cases.

7.8. Aversion

A number of cases have arisen where the treatment of a generally anxious dog with multiple phobias has resulted in a calm individual, free of all fears except a particular aversion to one thing. Visitors, for example, or the opening of a particular cupboard. Careful review of such histories may reveal that the dog has been punished by its first experiences and the offending stimulus is evoking anger or frustration or a flight/fight response rather than anxiety. Here again concentrating on the residual problem with the support of a medication effective in allaying frustration or anger is the appropriate course for continuance. A lifetime of aggressive responses may hinge upon a single frustrating or painful experience just as one fear inducing episode can lead to a lifetime of phobia.

7.9. Fear aggression

Cases are rarely reported where the diagnosis of fear aggression has been made and anxiolytics seem to facilitate more aggression. The first thought in such cases might be that the selection of tactics from the options - fight, flight, freeze or flirt, has been centred upon fight because the dog has lost a fear of self-harm which might have previously restrained the more risky choice.

After all, anxiolytic doses of alcohol seem to promote reckless driving of automo- biles. Moderate doses of benzodiazepines have be incriminated in cases of baby-batter- ing by medicated mothers. Careful analysis must be made of circumstances and human

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influences. Attempts to dominate or control a fearful individual in situations where it cannot escape or where its attempts at submission or appeasement do not relieve the threat may induce the adoption of aggressive defence. It should be remembered that reduction of fear may reduce tolerance of frustration in some individuals. Cases are on record where dogs on diazepam, phenobarbitone or acetylpromazine have done exten- sive damage to doors and floors in frantic attempts to escape isolation. Medicated dogs still digging at the surroundings until claws are completely avulsed and teeth broken are commonly recorded and the question must be asked - was the self harm greater or the medication?

7.10. A paradigm

An example may serve to illustrate the concepts assembled so far. A behaviorist assessing a puppy or a veterinarian examining and vaccinating one will face an opportunity to employ the principles discussed above. A fearful puppy may freeze and exhibit either bradycardia or tachycardia. Faced with either the novelty of the situation or what it might perceive as signals of impending punishment (an activated B.I.S.) the moment is ripe for misfortune. Should the puppy be alarmed by handling or an injection it may select a flight or fight strategy. At this critical moment the humans in attendance, in particular the owner, must not signal concern by conciliatory touching, movement or sounds. The puppy left to assess the situation will perceive that no punishment ensues and the emotional state will have the opportunity to change from fear to relief. The signs of relief are tail wagging and tentative approach. The emotional sensations of relief are elation and pleasure. This is the moment to reward by touch or titbit. Training regularly collapses in failure when the animal is rewarded for experiencing fear and displaying avoidance.

The central principle of behaviour shaping and training is the reward of an approach (non-fearful) behavior sequence. The animal must select it and experience something emotionally rewarding.

7.11. Does a dog learn new behaviors or new moods whilst on medication?

This is the crucial question for the behavioral scientist. The definitive tests will have to prove that learning is enhanced by a given treatment in preference to another. The clinical anecdote can only suggest that the reduction of fear in the dog is facilitated by propranolol. The work of Cahill et al., 1994 cited above is promising. The known ability of propranolol to prevent development of long-term potentiation in field CA3 of the hippocampus may be the basis of some ‘gating’ effect against inputs of emotional significance. Cahill et al. have indicated that whereas animal studies suggest that enhanced memory associated with emotional arousal results from an activation of adrenergic stress hormone systems during and after an emotional experience; propra- nolo1 significantly impairs human memory of emotional events, but not of emotionally neutral events. Such an effect may be occurring in the medicated canine phobia cases described here. It may not be unreasonable to suggest that the anxiolytic adjusts the behavioural inhibition system to reduce arousal, vigilance and the inhibition of ongoing

288 R. Walker et al./Applied Animal Behoiour Science 52 (1997) 275-289

behaviour. The receptor blocker might reduce the internal cues of physical discomfort (tachycardia etc.) and in addition have the effect of ‘damping’ the significance of the formerly feared stimulus result in refreshment of memory at a lower level of signifi- cance with each successive exposure. Presumably this is the result hoped for after the employment of graded exposure with relaxation or counter conditioning techniques.

Finally the propranolol might confer advantages in the withdrawal phase of the anxiety therapy by blocking withdrawal effects which seem to be associated with termination of drugs operating at the benzodiazepine receptor (Rickels et al., 1983). The pro-convulsive rebound of excitability seen after termination of long term alcohol, barbiturate or benzodiazepine medication may be prevented by careful withdrawal regimes plus a later phased withdrawal of the /3 receptor blocker.

7.12. Selective serotonin uptake inhibition - jluoxetine

A cohort of cases is being assembled relating to dogs which have been assessed as being frustrated or angry in certain contexts. Typical cases are retrieving breeds punished in puppyhood for retrieving, herding dogs punished for herding activity and frustrated strongly bonded dogs isolated from their owners. The diagnoses are on occasion confirmed by ineffective anxiolytic trial. Fluoxetine (Prozac) is proving highly effective. An apparent ability to learn a new behavior pattern is emerging. The notion that serotonin enhancement may facilitate memory for new mood and modified behavior seems to be supported by recent work on anxiety in the cat. The sum of veterinary experience in treating anxiety related urination by the cat suggests that benzodiazepines and progesterones can reduce urination in roughly 50% of cases, but the relapse rate on withdrawal of medication is very high. Medication with the serotonin receptor agonist buspirone gives a similar rate of urination reduction but the relapse rate is very much lower. It is tentatively suggested here that such a result might reflect the relative memory interference propensities of benzodiazepines and progesterones, and their possible association with anxiety rebound on withdrawal. Indications are that serotonin enhancing drugs may not have either of these drawbacks (Hart, 1994). Such compar- isons are necessarily conducted without making changes to environment or management to exclude such variables from the assessment of relative efficacy. However, failure to provided the reliefs and rewards that environment changes can give has the major disadvantage that the enhanced memory or new mood lacks the positive associations vital to the storage of altered emotional experience.

8. Discussion

The treatment of phobias is an area where the urgency of achieving alleviation of suffering in an animal and (often) its owner takes precedence over creating opportunities for academic or scientific self-advancement. Cases cannot be treated with placebos or selectively denied behavioral modification as they tend to arrive in extremis, often after extensive failed training or medication. The animal is often facing disposal and the owners are usually self described as ‘at the end of their tether!’ Eventually a sufficient

R. Walker et al. /Applied Animal Behaviour Science 52 (1997) 275-289 289

mass of raw data may provide opportunities for comparison of different drug efficacies; for use of the animal as its own control when medication has been intermittently removed and reapplied with recorded contrasts, and for evaluation of concomitant behavior modification techniques. It is hoped that this discussion might provide some basis for organization of further study.

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