How to Deal with Anxiety and Distress Responses: Dogs
Atlantic Coast Veterinary Conference 2001
Karen L. Overall, MA, VMD, PhD, DACVB, ABS Certified Applied Animal Behaviorist

Fears, anxieties, phobias, and stereotypies (obsessive-compulsive disorder)

Introduction: Fears, phobias, anxieties, and stereotypies or obsessive-compulsive disorders are among the most difficult behavioral problems to diagnose and treat. There is probably no other area in behavioral medicine that is fraught with much confusion and opinion. Fear and anxiety are probably closely related, but may not be identical at the neurophysiological level. It is worth remembering that when one diagnoses a problem related to fear or anxiety one is doing so at the level of the phenotypic or functional diagnosis, but such conditions are treated at this level and, when psychotropic medication is used, at the neurophysiological level. This chapter addresses approaches to diagnosing and treating fears, anxieties, phobias, and obsessive compulsive disorders.


Cautious and discrete use of terminology will lead to clear thinking. With that in mind, a list of accepted definitions follows. While these definitions are clear, the conditions for which they are relevant may be multi-factorial and heterogenous. Diagnosis may not be as simple or clear-cut as a definition. We do not understand the manner in which the "causal" levels interact to produce the problem - all we can evaluate is the form that interactions takes phenotypically. Clear use of terminology can help to make apparent the parts that are consistent and that we can understand and separate them from those that are more complex.

General definitions:

Abnormal behavior: Activities which show dysfunction in action and behavior.

Mental disorder: "Clinically significant behavior of psychological syndrome or pattern that occurs in an individual and that is associated with present distress (e.g., a painful symptom) or disability (i.e., impairment in one or more areas of functioning) or with a significantly increased risk of suffering death, pain, disability, or a loss of freedom." (APA, 1994). Regardless of cause, the disorder is a "manifestation of a behavioral, psychological, or biological dysfunction in the individual." (APA, 1994).

Fear: A feeling of apprehension associated with the presence or proximity of an object, individual, social situation, or class of the above. Fear is part of normal behavior and can be an adaptive response. The determination of whether the fear or fearful response is abnormal or inappropriate must be determined by context. For example, fire is a useful tool, but fear of being consumed by it, if the house is one fire, is an adaptive response. If the house is not on fire, such fear would be irrational, and, if it was constant or recurrent, probably maladaptive. Normal and abnormal fears are usually manifest as graded responses, with the intensity of the response proportional to the proximity (or the perception of the proximity) of the stimulus. A sudden, all-or-nothing, profound, abnormal response that results in extremely fearful behaviors (catatonia, panic) is usually called a phobia.

Phobia: A sudden, all-or-nothing, profound, abnormal response that results in extremely fearful behaviors (catatonia, panic) is usually called a phobia. An immediate, excessive anxiety response is characteristic of phobias. Phobias usually appear to develop quickly, with little change in their presentation between bouts; fears may develop more gradually, and within a bout of fearful behavior, there may be more variation in response than would be seen in a phobic event. It has been postulated that once a phobic event has been experienced, any event associated with it or the memory of it is sufficient to generate the response. Phobic situations are either avoided at all costs, or if unavoidable, are endured with intense anxiety or distress.

Anxiety: Anxiety is the apprehensive anticipation of future danger or misfortune accompanied by a feeling of dysphoria (in humans) and, or somatic symptoms of tension (vigilance and scanning, autonomic hyperactivity, increased motor activity and tension). The focus of the anxiety can be internal or external.

Vacuum activity: An activity involving an instinctive, unconscious, or response behavior in the absence of the stimulus that would elicit that behavior. Such activity seemingly has no apparent, contextual, useful purpose.

Displacement activity: An activity which is performed out-of-context, or "displaced", because the animal is "frustrated" in its attempt to execute another activity or otherwise occupy itself. This is considerably less specific than redirected activity which implies a substitution of behavior "in kind", but towards another target. In cases where displacement activity is involved the activity may not be "in kind".

Redirected activity: Direction of an activity away from the principal target and toward another, less appropriate target. This is usually best identified when the recognized activity is interrupted by the less appropriate target or by a third party, and, in contrast to displacement activity, redirected activity appears to be a substitution "in kind" of the interrupted behavior.

Stereotypy: A repetitious, relatively unvaried sequence of movements which have no obvious purpose or function, but that are usually derived from contextually normal maintenance behaviors (e.g., grooming, eating, walking). Inherent in the classification of dysfunction is that the behavior interferes with normal behavioral functioning.

Obsessive-compulsive disorder: An APA classification of abnormal behaviors that have as characteristics recurrent, frequent thoughts or actions that are out-of-context to the situations in which they occur. These behaviors can involve cognitive or physical rituals, and are deemed excessive (given the context) in duration, frequency, and intensity of the behavior. One of the hallmarks of this condition that distinguishes it from motor tics, et cetera, is that OCD behaviors follow a set of rules created by the patient. The condition in domestic animals is probably similar and analogous through descent, and probably includes stereotypies, self-directed behaviors, et cetera. Regardless, the behavior must be sufficiently pronounced to interfere with normal functioning.

Separation anxiety: When animals exhibit symptoms of anxiety or excessive distress when they are left alone the condition is called separation anxiety; however, the most commonly exhibited behaviors (elimination, destruction, excessive vocalization) are only the most visible signs of anxiety. Drooling, panting, and cognitive signs of anxiety will not be diagnosed but probably occur.

Necessary and sufficient conditions for selected behavioral diagnoses associated with anxiety in small animals: (adapted from Overall, 1997)

Behavioral Diagnosis: Cognitive dysfunction

Necessary and Sufficient Conditions: Change in interactive, elimination, or navigational behaviors, attendant with aging, that are explicitly not due to primary failure of any organ system.

Behavioral Diagnosis: Dominance aggression

Necessary Condition: Abnormal, inappropriate, out-of-context aggression (threat, challenge, or attack) consistently exhibited by dogs towards people under any circumstance involving passive or active control of the dog's behavior or the dog's access to the behavior.

Sufficient Condition: Intensification of any aggressive response from the dog upon any passive or active correction or interruption of the dog's behavior or the dog's access to the behavior.

Behavioral Diagnosis: Noise phobia

Necessary and Sufficient Conditions: Sudden and profound, non-graded, extreme response to noise, manifest as intense, active avoidance, escape, or anxiety behaviors associated with the activities of the sympathetic branch of the autonomic nervous system; behaviors can include catatonia or mania concomitant with decreased sensitivity to pain or social stimuli; repeated exposure results in an invariant pattern of response.

Behavioral Diagnosis: Obsessive-compulsive disorder

Necessary Condition: Repetitive, stereotypic motor, locomotory, grooming, ingestive, or hallucinogenic behaviors that occur out-of-context to their "normal" occurrence, or in a frequency or duration that is in excess of that required to accomplish the ostensible goal.

Sufficient Condition: As above, in a manner that interferes with the animal's ability to otherwise function in his or her social environment.

Behavioral Diagnosis: Separation anxiety

Necessary Conditions: Physical or behavioral signs of distress exhibited by the animal only in the absence of, or lack of access to the client.

Sufficient Conditions: Consistent, intensive destruction, elimination, vocalization, or salivation exhibited only in the virtual or actual absence of the client; behaviors are most severe close to the separation, and many anxiety-related behaviors (autonomic hyperactivity, increased motor activity, and increased vigilance and scanning) may become apparent as the client exhibits behaviors associated with leaving.

Separation anxiety in dogs: Separation anxiety is one of the most common and most devastating behavioral conditions diagnosed world-wide in pet dogs. It's been estimated that in the average veterinary practice in the U.S. a minimum of 14% of canine patients exhibit signs of separation anxiety . As is true for most behavioral conditions, the signs associated with separation anxiety are non-specific, and for dogs to improve an accurate diagnosis must be made. This handout is designed to help the average practitioner diagnose and treat canine separation anxiety.

Dogs with separation anxiety usually destroy objects in the house, destroy sections of the house, or urinate, defecate, vocalize, or salivate when they are left alone. The amount of time that they can be left alone without exhibiting these signs can be extremely variable. In profound cases of separation anxiety, dogs can be left alone for no more than minutes before they begin to panic and exhibit the behaviors associated with their anxiety. For some patients, the behaviors associated with distress are most pronounced within the first 30 minutes of absence, whereas other patients are distressed throughout the absence, regardless of length. Few quantitative data that characterize the different populations of dogs with separation anxiety are available; however, there is universal agreement that dogs exhibiting these signs are distressed and need help. In the absence of treatment the outcome for affected dogs usually involves relinquishment to a humane society or shelter, abandonment, or euthanasia. These otherwise wonderful pets can be successfully treated, if the veterinarian and the client understand the signs and work together.

In many cases of separation anxiety, the inappropriate behavior is only apparent after a schedule change. For instance, the dog may be fine until 5:30 or 6:00 at night when the client is accustomed to coming home. If the client's schedule changes and now they are not home until 7:30, the dog may start to panic at 6:00 o'clock.

There are idiopathic changes that occur in some older dogs and, for no apparent reason, a dog who has been able to be left alone for all his or her life can no longer be left alone.

Separation anxiety can develop gradually, or quickly when associated with an horrific event. These events include being caught in a fire, or being in the house when a burglary was attempted, or being trapped in the house when an alarm system went off. Dogs in these situations may have a worse experience than dogs for whom separation anxiety develops more gradually, and may benefit from immediate treatment with anti-anxiety medications combined with behavior modification.

There is also variation in response to being left alone that appears to be associated with the person who elicits the distressed response. Some dogs with separation anxiety cease to exhibit the problematic behaviors if they are left with any human or if someone comes to stay with them. These dogs can go to doggie-day-care or have a pet-sitter, but this management choice is not an option for dogs who must have certain people or a specific person stay with them. Such dogs still exhibit the signs of separation anxiety even if someone else is home with them.

Finally, some dogs exhibit signs associated with separation anxiety when they are separated from one special person or any person by any barrier, like a door or a shower stall. These dogs are extreme, and may need people more than want them since they are distressed by "virtual", rather than "real" absences.

Risk factors: Dogs that are at risk for separation anxiety include those rescued from humane shelters, those rescued from lab situations, those rescued from the street, and those who have spent extended periods of their life in kennels, or with one older housebound person. Part of the risk with re-homed pets is probably associated with the fact that signs associated with separation anxiety are one of the most common reasons that animals are relinquished .

Data collected at the University of Pennsylvania, School of Veterinary Medicine Behavior Clinic indicate that if a dog had history of separation anxiety earlier in it's life, it may be more easily at risk for developing it again later. Invariably, relapse events are more complicated and worse than were the earlier presentations of the condition.

Making the diagnosis: Elimination, destruction, and vocalization are the most obvious and hence the most commonly reported behaviors associated with separation anxiety. It's important to realize that clients complain about these behaviors because they are easy to recognize and are problems for the client. However, it is less easy to recognize dogs that are distressed when left, but exhibit less obvious signs like withdrawal and inactivity, salivation, soft whimpering (or frank barking and howling if there are no near neighbors), and pacing. These dogs are equally affected by separation anxiety, but their problems are not problems for the clients, so they seldom get help. With these dogs included, the population of dogs with separation anxiety is large indeed, and all dogs can benefit from treatment.

It is important to note that fear is not uncorrelated from separation anxiety, and that the interaction between these is poorly understood. When signs of separation anxiety appear in older dogs they may be associated with anticipatory anxiety . It is on this observation the development of the concepts associated with "cognitive dysfunction" in older dogs have been predicated. Failure of function or behaviors associated with anxiety are not uncommon in older dogs. Thirteen of 26 dogs 10 years or older were diagnosed with separation anxiety (i.e., the behaviors occurred only in clients' absence), while 6 were attributed to breakdown of house training (i.e., "cognitive dysfunction") that did not meet the necessary and sufficient conditions for separation anxiety. Older dogs have changing physical and emotional needs; accommodating these needs and treating the dogs with anti-anxiety medications can help modulate symptoms, although the course of whatever the underlying condition is may be inexorable.

Studies that have examined client behavior and the development of separation anxiety have demonstrated no association between the former and the development of the latter. Studies specifically seeking to find causal associations between client attachment to their pet and separation anxiety have failed to do so, although one manifestation of separation anxiety, that involving "virtual" absences may involve dogs that are abnormally needy.

Approximately 20-30 % of human patients with major depressive disorder have panic attacks. Life-time incidence of panic attacks in depressed groups may reach 50-60 %. Panic attacks are more easily recognizable in pets than is depression; however, the covariation in humans suggests that we may be missing the extent to which the signs associated with depression are present in animals. It would be interesting to investigate the extent to which dogs with known panic responses had experienced behavioral changes that can be concordant with depression. Panic may be identifiable as a component of thunderstorm phobia.

In the Behavior Clinic population at the University of Pennsylvania School of Veterinary Medicine, the probability that a patient whose primary problem is separation anxiety is correlated with the probability that the patient also has a thunderstorm phobia. When these diagnoses co-occur the signs of each are worse and more intense than when either occurs alone. In human medicine, separation anxiety is seen as an important antecedent or current affect in panic disorder. Separation anxiety is prevalent as an undercurrent in the dreams of panic disorder patients. This suggests that in humans, as in pets, separation anxiety can occur separate from panic disorder, but that when the two co-occur the interaction is an important factor in the assessment and treatment of either. These findings strongly suggest that adverse reactivity to noises may predispose a dog to separation anxiety, and that unless veterinarians carefully question clients about the pet's behavior both of these conditions could remain undiagnosed. The extent to which early fearful behaviors contribute to the development of separation anxiety is unknown.

The best treatment of separation anxiety involves the combined use of medication and behavior modification.


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Karen L Overall