Autism and Auditory Hypersensitivity: Causes and Treatment

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A recent report from the U.S. Department of Health and Human Services indicates that autism spectrum disorder prevalence has significantly increased to over 2% of all children in the United States, with an estimated 1 in 28 boys currently with an autism diagnosis.

Professionals working with children diagnosed with autism spectrum disorder (ASD) may find that these children are overly sensitive to sounds. These professionals and parents are often concerned as to why children may have auditory hypersensitivities.

The journal Autism Research and Treatment recently published a peer reviewed article which discusses the neural mechanisms identified underlying hypersensitive hearing in people. I wrote this article with Dr. Jay R. Lucker of Howard University. Our article focuses on brain research to support the idea of the non-classical auditory pathways being involved in connecting the auditory system with the emotional system of the brain. We also discuss brain mechanisms believed to be involved in auditory hypersensitivity, and treatments for hypersensitive hearing.

This Wednesday, February 3rd at 8 pm Eastern, Dr. Jay R. Lucker will join me on The Listening Program Radio to discuss the topic of Autism and Auditory Hypersensitivity, the causes, treatment, and hope for those suffering from sound sensitivities.

Register here for this free program and to ask us a question we can answer live. You’ll receive an email with the call-in number and a web link to listen online 3 hours before the show.

Could a Simple Hearing Test Diagnose Autism?

Big Ear

A recent study published in Autism Research is stirring controversy over reports that a simple hearing test may help with early autism diagnosis. The test is the auditory stapedial reflex (ASR) test which measures how one of the two middle ear muscles called the stapedius contracts in response to loud sounds.  According to the authors of the study an absent reflex would indicate an autism risk factor.

The reflex attenuates sudden loud sound to protect the delicate inner hair cells from damage. Without this sound dampening the auditory system is bombarded by sound which results in a number of behavioral responses such as covering of ears, running from the sound, aggression, and more.  These are characteristically fight/flight behaviors seemingly in response to sound, in this case a stressor. Last year I published an article with Dr. Jay Lucker in Autism Science Digest identifying that in most cases the response is an emotional rather than auditory response that can be trained with music listening therapy and behavioral techniques and is not exclusive to people diagnosed with autism.

If you read the research abstract (link below) you’ll see the investigators are making an argument for absent reflexes as an autism biomarker. My concern is they tested children with autism compared to a smaller group which was “neurotypical” but not other neurodevelopmental disorders which based on my experience would very likely yield the same results… Auditory deficits are a common feature in autism chief among them hypersensitivity to sound in which the brain appears unable to filter out undesirable sound resulting in pain or discomfort.  However this is also true of Sensory Processing Disorder, ADHD, Auditory Processing Disorder, etc.

I’m pleased to see the attention on the auditory system in the autism research field, but caution looking to the ASR as a reliable autism biomarker without further study. What are your thoughts?

Abstract:  Quantification of the Stapedial Reflex Reveals Delayed Responses in Autism Autism Res 2013

Happy 4th of July America!

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If you are an American like me, then very likely tomorrow will be filled with parades, bbq’s, and fireworks as we honor the adoption of the Declaration of Independence.

Hopefully also like me, you’ll be picking up ear plugs for you and your kids so you can protect your hearing when those spectacularly loud 140-165 dB fireworks start filling our skies in celebration of our freedom.

Our hearing is precious, let’s preserve it so we can enjoy the sweet sounds of liberty for years to come… You with me?

Happy 4th of July America!

 

Sleep Rhythms: And the Beat Goes On

Sound Brain Fitness Series

Your brain is a grey, wet, squishy pattern seeking machine.  From daily changes in light to microsecond scale responses to music and voices, your brain runs on and generates the rhythms of your life.  And because we are so rhythmocentric at such a basic level, events that violate your normal rhythms often have serious impacts on us.  The field of chronobiology examines how the timing of environmental and internal events affects our cognition, our health and our daily life, whether it’s transient like focusing on a task or longer term like getting enough sleep.

Next week is National Sleep Awareness Week 2013. To kick it off I’ve invited neuroscientist and author Dr. Seth Horowitz back as my guest for another episode of the Sound Brain Fitness teleseminar series. Please join us for this free teleseminar on Monday evening, March 4th at 8 pm eastern for what is sure to be an engaging hour as we explore:

  • Rhythms of the environment and how they affect the rhythms of the brain
  • Rhythms and patterns of sleep – where they come from and what they do.
  • Interrupted sleep patterns – the consequences of insomnia, disruption, and EDS
  • Weapons of choice – tools for resetting the sleep clock and their side effects
  • Why an auditory sleep aid may be right for you

I hope you’ll listen. You can register here.

Rock-a-bye Brain

A Good Laugh and a Long Sleep

Guest Post By: Seth Horowitz, Ph.D., Neuroscientist and author The Universal Sense

Sometimes the best science is done by looking at the obvious — the daily behaviors that we do — to solve a mystery.  And watching almost any sleep-deprived parent and his or her young child will give you an instant insight into two powerful mechanisms that underlie human sleep, one of neuroscience’s greatest mysteries, as the parent rocks his or her infant back and forth, crooning a lullaby.  These are two behaviors that have probably been used by humans seeking sleep for their children (and themselves) since humans first appeared, and both are driven by our ears.

It may seem odd to think that rocking someone to sleep has anything to do with your ears, but your ears contain two sensory systems — the auditory system for hearing sounds, and the vestibular system, which normally underlies balance.  Both are driven by similar types of sensors, called hair cells. These are tiny, tufted cylinders with tips that wave back and forth in fluid -filled chambers, each responding to different types of motion: oscillations of pressure waves that are translated into sound, and slower, linear or angular motions based on how the head moves (which drives balance).

Normally, the two systems are separate, projecting to different areas of the brain and helping define different ways in which we sense our environment.  But both systems can overlap under certain circumstances. Managing sleep is one of the most profound ways in which they interact.

Balance and the Vestibular System: your brain’s way of processing movement

One of the things that the balance system does is let us know when things are wrong with the way we are moving.  Standing on a boat in high seas, your vestibular system will tell you that the world is moving up and down at one rhythm, while your stomach and eyes are experiencing movement in different directions.  Radical motions that separate what your inner ears and your eyes tell you are happening trigger nauseogenic motion sickness.  But slow down the motion, make it almost regular, slower, and gentler, and your inner ears do something odd.  They put you to sleep.  Whether it’s a baby rocking gently or a passenger in a car, bus, or train, gentle vibrations transmitted through your body to your inner ears trigger another form of motion sickness. It’s called Sopite syndrome, and, rather than making you want to lose your lunch or die, it activates your global sleep network.  But it’s not always convenient to drive your child around on bumpy roads to get her to drift off, or possible to rock your baby in a quiet environment.

Low frequency sounds: feel the beat

This is where the other part of your ears can help.  While normally there is no cross talk between your hearing and balance system, high pressure/low frequency sounds can trigger responses in the balance-sensitive hair cells in your ears.  This is why most effective dance music pumps up the bass, hijacking your sense of hearing to trigger motor responses. In other words, rhythmic deep bass sounds make you feel the beat and want to match it with body motion.

But the truth is, we don’t hear very low frequency sounds very well, and even sound pressure levels of 70 dB — what would seem like a moderately noisy street or bar scene at higher frequencies — are perceived as relatively quiet at lower frequency.  And here lies the opportunity.  By providing semi-regular, low frequency sounds that are audible, but not loud enough to make you want to dance or run away, you can trigger Sopite syndrome and provide a gateway to sleep.  And by providing soft, regular sounds in a familiar register (like the universal aspects of lullabies, which stretch back more than a thousand years), you block out the distracting environmental sounds that can interrupt falling asleep.

The Listening Program® SLEEP uses those combinations of sounds so that your ears tell your brain it’s time to sleep. You may not feel like you’re being rocked like a baby, but your brain will get that impression. And it’s all due to the two functions of your ears.

So the next time you do bundle your cranky child into the back seat of your car and finally get her to fall asleep, remember to thank her ears.  Just make sure you don’t let yourself get lulled by those very same inputs to your own brain.

Follow @SethSHorowitz

Sleep is not simple unconsciousness

Sleep Quote- Dr. Seth Horowitz

Sleep is one of the most important functions for daily life and continued health throughout the lifespan, yet it is one of our least understood behaviors. Our scientific understanding of sleep has evolved from thinking of it as a simple cessation of consciousness to realizing it is a complex neural behavior that is easily affected by everything from light exposure to diet and exercise. One of the most powerful ways of affecting sleep, for good or bad is through sound, as hearing is the only sense that remains highly active through most stages of sleep.

Tonight please join me and my guest, neuroscientist and author Dr. Seth Horowitz, as we examine the interactions between sleep and the auditory system, and how sound can be a powerful stimulus for both sleep interruption or induction and maintenance of healthy sleep patterns. The free teleseminar begins at 8:00 pm, Eastern.  Please note that registered callers will be first to call first served. We have capacity for 250 on the call, and up to 500 can listen on the web if the phone lines are full.  We will exceed capacity. I hope you’ll join us to learn more about sleep and to be the first to hear a special announcement that will offer new hope for the sleepless.  Register

Balloons for your Ears?

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Ears buds, you’ve heard me on my soapbox about the inherent danger of sticking these things in your ears and blowing out your hearing.  Apparently, Stephen Ambrose, a pioneer in audio technology and founder of Asius Technologies has an alternative solution to ear buds that I find intriguing.  I call them balloons for your ears, he calls them inflatable ear buds and they may be coming soon to an Apple store near you.  I’ll reserve comment until I test them personally, and deliberate the advantages and disadvantages with my audiophile and audiologist friends. This includes you Seth Horowitz and Jay Lucker! Perhaps Stephen Ambrose will send me a pair to review?  For now, you might be interested to read more on this innovation on Mashable.

Tell me, would you be comfortable with inflatable airbags in your ears?