Sensory Defensiveness Or Sensory Overload

Did you ever lie awake in bed at night unable to sleep because of the sound of a dripping faucet? Did you ever feel enraged because someone sitting near you was chewing gum and making sounds while dong so? Are you someone who would like to wear a turtle neck sweater during the cold weather but cannot because it feels as though the touch of the fabric on your neck and throat is strangling? Do you react badly by the sudden and unexpected touch of someone, even if its someone you know and love? If you are familiar with any of these experiences you then have a good idea of what sensory defensiveness or sensory overload is all about.

However, what distinguishes you from those who fit the full diagnostic category of sensory defensiveness is that there are multiple stimuli that the sensory defensive person finds intolerable. As a result, daily life is deeply affected because it is difficult or impossible to work, have a relationship or engage in social interaction with other people. The reason for these limitations is that there are so many stimulating factors in the environment that cause real irritation that the individual is distracted and therefore, incapacitated. Many of these people withdraw into social isolation and this isolation as well as the sensitivity to stimuli, are depressing.

In sensory defensiveness, multiple things are experienced as alarming, and are negatively reacted to. It is important to stress that these over stimulating items are minor and do not bother or annoy the average person. For those who with sensory overload, many or all of these things are intolerable. Commonly, there can be a startle response to irritating stimuli. Another common response is extreme anger that other people find disconcerting if not totally unacceptable.

This terrible experience of intolerance can affect everything from the taste and texture of certain foods to many types of sounds, lights and clothing fabrics and even temperature. 

People with this disorder have a lot of variability with regard to what things will be overwhelming and to what degree someone is overwhelmed. It is possible to have a sensory defensiveness to a degree that is mild, moderate or severe.

It is not completely clear what causes this disorder. There is evidence that such factors as Premature Birth, Alcoholism, Drug Addiction, Autism, PTSD, ADHD and Brain Injury due to head trauma, can contribute to the start of hypersensitivity to stimuli.

Conditioning is sometimes used to help people with this condition. This means that they are exposed to very calming stimuli to help counteract the negativer response to things that are irritating. Ultimately the person must learn to use these calming strategies by themselves.

Recent research shows that the part of the brain called the Thalamus might be involved in this hypersensitivity. The Thalamus, located in the middle of the brain, is a kind of relay station for all the sensory information that is relayed via the eyes, ears and other sensory organs. If the thalamus is damaged, it may disrupt the brain's ability to sort out and integrate all the sensory information coming into the brain. The use of fMRI technology and other types of brain scopes, are helping medical science understand what goes wrong in the brains of these people. It is hoped that this will lead to new and more effective techniques for the treatment of this disorder.

It is important to keep in mind that people with this condition are not deliberately behaving badly when they over react to something. This is not something they are choosing to do and would happily change it if they could.

If you know someone who may be experiencing sensory overload, including a child, it is important that they be seen by an MD so that the correct diagnosis can be made and treatment begun. Part of the treatment may include regular visits to a therapist who is expert in using conditioning and relaxation techniques.

Your comments and questions are encouraged.

Allan N. Schwartz, PhD

  • Anonymous-1

    I don't understand, however, how sensitivity is related particularly to major depression.

  • Don

    I'm BiPolar and have been for many years. I can't stand it when people come up and punch me in the arm, or slap on the back, or push me when they are telling a joke, while setting next to them.

    I can no longer being in a place where smoking is a part of a gathering, I'm an Ex-Smoker, and an Ex-Alcohol abuser.

    I don't like being around people who think they know every thing, about every thing. I just want to stay home and keep to myself.

    I don't like people who judge others, who knock people down, talk behind people backs, and then be real nice to them when they see them, or when they come to a event.

    My wife talks about me all of the time, and I've ask her to stop doing it. What happens in our home is our business, what happens in my life in my business. I feel like I'm being judge by her side of the family all of the time, when we go to a family gathering. However, she continues to do so, even on the phone, even when I ask her not to do it.

    I don't feel comfortable in gathers at all, especially if there inside.

    I tried theapy and it didn't work. As soon as my insurance ran out they dropped me like a lead ballon. So I reason its all about money, money, and more money.

    I've even tried the states mental health program. All they want to do is give you more and more drugs. I was on so many drugs that I couldn't even function. All the shrink did was ask how I was doing, how are your medications doing, and here is your refills. I just gave it up.

    So, I try, I take it one day at a time, I have my goods days which are far and in between and I have my bad days.

    Yes, I agree I'm defensive, I have a right to be, been screwed over by so many people that I really don't care to have any friend period. Sensory Overload, yep been there, and I'm still there. When some one hits me I tell them to please refrain from doing that to me. I really don't like it.

    I've accepted it, nothing more I can do about it.

  • Isobel

    One of the key factors in my illness was witnessing my mother having an electric shock wich burnt through her hand when I was 5. This had many consequences especially in my father's behaviour. I eventually broke down with severe depression 17 20 odd years ago.. Each time I have needed hospital (& thank God I live in the UK) I find that I emerge maybe fitter to deal with my psychological problems but with fewer resources. By that I mean that I still have my intelligence and skills but much less ability to use them. Sensory overload definitely contributes to this, especially random noise, like my husband eating crisps. (very crunchy), touch e.g. I cannot bear having bed clothes on my knees when I'm lying sideways, hair on my neck when I want to sleep, more than one person trying to speak to me or talking within my hearing etc. Until my last admission I was always very alert and reacted to far too much. Now I am not on the alert all the time but jump hugely when interrupted in anything by whatever means, touch, sound etc. This experience is exhausting. When I tell people about it they tend to compare it to themselves and miss the point or treat it as something unimportant. It is VERY important for me because it has major effects on what I can or cannot do. Next time I see my psychiatrist I will ask for a scan to see if there is any evidence of damage that may be contributing to my difficulties so that there may be some chance of help. My nose has been broken several times in the past, including by diving into the bottom of a swimming pool ( I forgot that I was in the shallow end).

    I also sometimes create my own overload by talking and talking about things that I feel important. Getting on my soapbox and finding it very hard to get off it again.

    Does anyone have any thoughts on all this please?

  • Brenda M

    A few months ago my son was diagnosed with SPD. Subsequently I have spent a lot of time researching this certain issue only to find out that I myself have some pretty extreme sensitivities which up until this point I have learned to manage, but not after going through some pretty serious hurtles. I was a "gifted" child.. certified genius in my state by age 7. I can honestly say I have spent the better part of my life feeling lost and confused, but it never dawned on me that how I was feeling was lost and confused. I am also an Addict in recovery for the last 8+ years and find this whole situation fascinating. I left high school before finishing and to put it nicely "entered the gates of hell". Thank goodness everything worked out well, but as an adult I have been told some of my pain could be conditions like fibromialgia and that my reading issues could be dyslexia. I have also experienced such intense sensitivities that it has affected me in many aspects of my life. I am more then positive that my sons diagnosis has helped me see an issue with myself. I only hope that my experience can benefit him and he will not need to go to extremes I have to find his place in life and be comfortable. Thank you for this article, it was eye opening.

  • Anonymous-2

    I've had my fair share of depression, therapists, psychiatrists and diagnoses but I feel like this is the first article to bring light to my condition in a decade, an aspect to explore that I haven't so much as had mentioned to me before. While I doubt any therapist can bring something new to the table for me, this is a new light shining in the tunnel that has been dark for some time.

  • Tara Quinones

    I had Brain surgery in 2012 due to a brain tumor and had a concussion in 2001. Ever since my surgery I 've been dealing with exactly what you described. It's not all the time, but everyday I will have some sort of episode of sesory overload. I've had difficulty describing it to my doctors and others, and could only describe it in comparison to a computer that takes long to process or load. Thank you for giving me the words to describe what I have been dealing with. I went back to work but this problem interfered and I did not have the ability to sustain it since it is very unpredictable. This experience has me thinking of changing careers into the physical health field.