Through a Dog's Ear Research

Current research into the effect of music on dogs consists of the following two research studies:

1. Wells, D. L., et al. "The Influence of Auditory Stimualtion on the Behaviour of Dogs Housed in a Rescue Shelter." Animal Welfare 11 (2002): 385-393
2. Wagner, S., et al. BioAcoustic Research & Development Canine Research Summary (2004).

Notes on the inter-relationship of the two research studies:

Dr. Deborah Wells, Belfast, Ireland In 2002, Belfast-based psychologist and animal behaviorist Deborah Wells undertook a research program to determine the influence of five types of auditory stimulation: human conversation, classical music, heavy metal music, pop music, and a silent control (no music at all).
From Dr. Wells's study, we came to understand that classical music had a marked soothing effect on dogs in animal shelters when compared to the other types of auditory stimulation. In the discussion section of her published research, Dr. Wells stated, "Classical music resulted in dogs spending more of their time resting than any of the other experimental conditions of auditory stimulation. This type of music also resulted in a significantly lower level of barking. Research suggests that calming music may have a beneficial effect on humans, resulting in diminished agitation, improved mood and lower levels of stress. Although the specific effect of classical music on dogs remains unknown, the findings from this study suggest that it may, as in humans, have a calming influence." She concluded that heavy metal agitated the dogs, indicated by increased frequencies of standing and barking, and that neither human conversation nor pop music had any apparent effect on the dog's behaviors, perhaps due to habituation to radio exposure.
Dr. Wells stated, "Further work is still required to unravel the specific acoustic elements that dogs respond to." That challenge inspired us to take our bioacoustic research where no one had gone before.

The Bioacoustic Research & Development Project, USA

Understanding that some things about classical music were having an optimum effect on dogs, we endeavored to take Deborah Wells's work one step further. The purpose of our BioAcoustic Research & Development project was to investigate the effects of multiple types of classical music on the behavior of dogs in kennel and home environments. The music was chosen and arranged according to the principles of entrainment (beats per minute) and harmonic complexity (active listening versus passive hearing). We know that dogs have the same brain-wave patterns as humans. However, dogs' heart rates vary according to size; the larger the dog, the slower the heart rate. The tempos used in this project were based on an average-size dog.

We also recognized that domesticated animals possess more highly tuned hearing than people, yet we did not know if animal cerebral function would allow them to recognize sonic relationships (i.e., intervals, harmonies, and fast or slow external rhythms). In short, effectuating change in the human nervous system with sound and music is known, but what would be the result using the same principles on dogs?

After highly specific recordings were made, we created two pilot studies, involving more than 150 dogs. Between June 2004 and September 2005, these dogs were observed while listening to different combinations of the recordings Lisa Spector made for the project, as well as the control CDs, which consisted of non-psychoacoustically- arranged classical music.

Two Pilot Studies

Pilot I. The purpose of Pilot I was to determine the efficacy of external rhythm and pattern identification on canines in the kennel and home environment. Four albums of psychoacoustically designed classical music were tested "” two albums of solo piano at varying tempos and two albums of piano trios, also at varying tempos. The results suggest that all classical music doesn't have the same effect on behavior in dogs:

• In the kennel environment, over 70 percent of the dogs became calmer with the simplified, 50-60 beats per minute (bpm) "” both solo piano and trio music.
• In the home environment, the solo piano at 50-60 bpm showed an average of 85 percent becoming calm, and over half the dogs went to sleep.

Pilot II. The purpose of Pilot II was to determine if music arranged according to psychoacoustic principles would have an effect on specific anxiety issues in dogs, such as fear of separation, thunderstorms, and fireworks. Upon review of the data from Pilot I, it was determined that the simple and slow piano CD showed the most consistent results for calming dogs in both kennel and home environments. Because many guardians turn the radio on for their pets when they leave home or when a thunderstorm is approaching, another CD of standard classical music was chosen for comparison. This music was taken from the play list of a San Francisco classical radio station and was not psychoacoustically rearranged.

Ten dogs with anxiety were used in Pilot II.
Their specific anxieties stemmed from the following:

• Other dogs or children
• Visitors in the home environment
• Thunderstorms
• Riding in the car
• Excessive need for attention "” pawing at guardian
• Separation anxiety
• Fireworks

Comments on the BARD study from Joshua Leeds:

What is fascinating, from a psychoacoustician's viewpoint, is the fact that dogs were reacting in a similar manner to music that had been created for specific effects on people. In other words, dogs could be entrained, i.e., heart rate, brain waves, and breath slowed or speeded up when influenced by external rhythms, just as in people. It is also intriguing to note that the complexity of sound affected dogs as it does people: the more complexity in the music, the more energy required to decipher it. Likewise, the simpler the sound, the greater the relaxation response.
The fact that this simple pattern identification process had an effect on dogs with anxiety issues is even more startling for it suggests that dogs suffer from over-stimulation in the same way that people do. Stimulus is defined as "something that produces a temporary increase of physiological activity."
We know from the extraordinary work of Dr. Alfred Tomatis that high-pitched (treble) sounds will stimulate and lower sounds (bass) de-stimulate the nervous system. (The first 80 percent of hearing cells in the inner ear process mid-high frequency tones. The remaining 20 percent of the cells process mid-low sounds. Dr. Tomatis discovered that if the ear is overwhelmed with too many low sounds, fatigue occurs and the brain does not receive the full benefit of the sonic energy. High sounds, on the other hand, create optimal stimulation.)
Of the five CDs used in the combined studies, the single CD with the most startling results was one designed specifically for human calmness. This CD is the first in the Through a Dog's Ear series. Entrainment "” the process whereby our internal pulses will match a periodic rhythm "” is easily observed in people who are tapping their toes and moving their heads to a rhythm. As we noted earlier, we have never witnessed a dog that pants or wags its tail to a beat. However, the results of these studies show that even without physical demonstration of rhythmic entrainment, the internal organs are still speeding up or slowing down to match external rhythmic stimuli. The ramifications of this are great. Our canine companions are totally impacted by the sonic landscapes in which we surround them "” and ourselves.

Psychoacoustics Meets Bioacoustics

An official definition of psychoacoustics is "a branch of science dealing with hearing, the sensations produced by sounds, and the problems of communication." Psychoacoustics may also be thought of as "the study of the perception of sound."

As a psychoacoustician, I study the effect of sound on the human nervous system. After a few decades of research and observation, I know that auditory input has a much larger impact on the psyche and body than most people think. When our auditory process is under- or overwhelmed, or when we have difficulty processing sound properly, there can be multiple and far-reaching ramifications.

One of the profound joys I have found in the clinical studies of music for dogs is the discovery that many of the same principles and effects of sound are shared by people and animals. This reinforces what soundworkers already know "” that sound is a potent energy that is not to be taken for granted.

Over the last fifty years, musicians, producers, and therapeutic professionals have clarified and innovated music and sound techniques that naturally affect our human body pulses "” brain waves, heart rate, and breath. We've learned to play the human body in a purposeful way. By adding the natural processes of resonance (the ability of one vibration to alter another), entrainment (the effect of periodic rhythms to speed up or slow down the brain, heart, and breath), and auditory pattern identification (determining when it is conducive for the brain to be in an active or passive mode) to the musical palette of harmony, melody and form, it is now possible to create potent soundtracks for specific purposes.

But what does psychoacoustics have to do with the health and well-being of our canine companions? This is where bioacoustics comes into play. The Acoustical Society of America defines animal bioacoustics as the study of sound in non-human animals. Like psychoacoustics, it is a branch of science that deals with the relation between living beings and sound.

"“ Joshua Leeds