Sensory & Processing

Following most brain injuries, complex cognitive changes may develop. Everyday levels of particular stimuli, such as bright lights, loud noises, or smell, are now uncomfortable, overwhelming, and distressing. This problem is referred to as hypersensitivity, overstimulation, or sensory overload. This may lead to fear, anxiety, and avoidance of particular stimuli, such as keeping curtains drawn to avoid light, or avoiding noisy situations such as stores or malls. Changes in sensitivity and hypersensitivity may occur, in the context of damage to certain sensory structures, in this case sensory organs, the central and peripheral nervous systems, relevant to the experience of particular sensory symptoms. Sensory overload can also arise in the absence of any actual structural damage to the sensory pathways. It may arise as the result of cognitive impairments of processing and attentive parts of the brain, known as a processing jam.

Overload vs overcompensation –

When it comes to senses and the brain, it is important to draw the distinction between overload and overcompensation. Sensory overload is either related to damaged sensory structures which prevent proper collection of sensory input, or the sensory information running into a bottleneck because the sensory processing part of the brain is damaged. On the other hand, overcompensation is the result of deficits where the brain is overworked trying to reconcile what it already knows against the sensory input received.

Our experience

After my brain surgery, which happened years after my accident, and resulted in additional brain injury symptoms, a friend of mine came into town to visit and check on me. During the day, we spent time catching up at my house. Later in the evening, he decided to take me out for a treat, to a nightclub. We always had much fun at nightclubs with spotlights and loud music, and yes, we both came from the disco era. He drove, and when we arrived at the nightclub, I remember walking through the long and wide archway entrance, then receiving the blast of sound and light that was so familiar to me. Except this time, I stopped midway through the entrance, with my hands over my ears and head, overwhelmed and shocked. I can remember freezing like this for a bit, with my friend walking ahead, until he realized that he had left me behind. It took me a minute to regain my being, then I pointed my friend toward the door, and we walked out. He asked me what happened, and after a bit of time to recover, I explained that my head was about to explode. I knew that my head had not been feeling right, but I did not know I would feel this way in a place that was so familiar to me. Was this sensory overload or brain processing jam? I had no clue then what all that meant, and anyone who is familiar with the subject would say that it could have been either or both. But today, I can tell you that it was likely a brain processing jam, since I have had no issues with my vision or hearing over the years, except for a brief period of double vision after my accident.

This is how this experience has felt from the inside. In contrast, here is what I have witnessed with Sarah, watching from the outside. After Sarah’s final Gamma knife surgery, and while visiting her and her husband in their little student apartment, her girlfriend along with her husband stopped by to say hello. Shortly after they walked in, I noticed that Sarah was pacing around with her hand over her head in a clear struggle. This struggle seemed to be happening as a reaction to the male visitor, as he talked loud and moved around a lot. Yes, he was a bit loud and animated, but nothing extreme. Then it hit me, the reaction to his presence was the obvious result of his loud voice and constant animation. Soon after, we found a way to let the visitors know that she was not feeling well, and they left. Afterwards, I only had one question to ask her, what was this about? Her explanation matched my fear, something about his voice pitch, mainly, along with his body animation, drove her to sensory overload or caused a brain processing jam. Was it sensory overload or brain processing jam? Sarah never had hearing problems before, during, or after her brain injury. But she did have right superior vision deficiency, as she can’t see out of the top right quadrant of both eyes, and bright sunlight can trigger her seizures. She also just had her brain cooked with Gamma radiation, right at the sensory processing area. So, it is really hard to say whether this was sensory overload or brain processing jam.

My personal experience with sensitivity episodes to light and sound was mild to moderate in severity with varying longevity. But I muscled my way through it, with the shame of sharing, and until things worked themselves out. Sarah, on the other hand, had vision deficiency and a moderate sensitivity to bright light. Sometimes those sensitivities triggered episodes of seizures. Added to that, her last Gamma radiation was focused toward the sensory area on the left side of her brain, which resulted in that area being cooked with radiation. This had possibly caused more brain injury and likely caused her hypersensitivity to explode, and her seizure episodes to become extreme. Sarah and I had several conversations about what was going on and how to handle it. The complexity of the matter was that she was okay listening to music and watching TV. What did that mean, then? Was it specific sound and light frequencies? What about the smell? Why was she reacting to certain odors, but was okay with the smell coming from her husband’s awesome cooking? Over the next couple of months, she started to make many specific modifications to her little apartment, to avoid certain lights, sounds, and smells, and it helped.

Another example: During the same visit, Sarah and I tried to take walks in her neighborhood during the day. But unlike before, she was not able to take a walk while the sun was out, even though she was wearing sunglasses. She tried to tough it out several times, perhaps to appease her visiting father. But every time she did, sensory overload came rushing in, and she would suddenly stop, lean on a wall, or sit quickly wherever possible. At home, I also noticed that she started closing the curtains inside her little place when the sun was shining through. Her hypersensitivity to sunlight was obvious. In the end, we agreed that she should try to switch her sleep and activities, sleep by day and live by night, I think that’s a movie! She started a transition to stay up most of the night and wake up shortly before sunset, and that has helped a lot.

Remedies

whether sensory overload or brain processing jam, the ending result can be similar in symptoms, and you can do some work to help decipher and mitigate. For example, get in depth vision and hearing testing, to figure out your injured brain’s weakness, whether it is sensory structure deficit or damage to the part of the brain that processes sensory input. You can also walk back your symptoms while looking for ways to customize your atmosphere so that it is agreeable to your sensory and brain processing power. Find out the situation of light, sound, and smells that cause your symptoms, and change or eliminate them. You can also get geeky and study the spectrum of frequencies, and learn how to determine which light and sound frequency range is better for you, and apply. Two examples, you can buy light bulbs with different lumens and color temperatures according to your comfort. Also, you can use an equalizer for your sound, which will allow you to control the sound frequencies according to your desired pitch. It works.

Note – We are currently experimenting with interesting technology-based tools to help with sensory overload and brain processing jam. Please see VR-Therapy.