The Not So Straight Forward Science of Sleep (Autism Edition)
Using Brain-Computer Interfaces to revolutionize the research of sleep disturbances in individuals with Autism Spectrum Disorder.
For those unfamiliar with the terminology used when discussing neurodevelopmental conditions, I’ll include a little preface for context purposes.
“Neurotypical” refers to a brain type representing the median of the human population (around 68% statistically). On the other hand, the terms “Neurodiverse” and “Neurodivergent” both reference brain functioning that is opposite from those that have neurotypical brains.
The much-desired eight-hour snooze seems to be a rite of passage that odes to the traditional human circadian rhythm. Although, for individuals with irregular neurological physiologically, this habitual rest pattern is closer to resembling a parabolic rollercoaster track.
This begs the question; Why do sleep patterns differ from person to person?
Normally, when the human body partakes in an action of a repetitive nature, we expect consistent results.
To preface this argument, I’d like to share my experience with sleeping…
As an autistic person, I can first-hand account for my issues regarding sleep or at least the lack of it. From an early age, I just never found pleasure in the simplicity of resting. Whether it would be the existential dread after watching my favourite television program end or the lack of consuming any other stimuli, I could never find peace in letting my body shut off.
Introduction to Sleep
Many like to think that sleep begins the moment that you close your eyes. This part of the sleep cycle is called “quiet wakefulness” it’s the preliminary stage that the majority of us enter before falling asleep. In this portion, your neurons reach a somewhat irregular pattern, one that differs from the typical constant firing that occurs when we are awake.
Once one reaches the second phase of the sleep cycle, also known as the non-rapid eye movement stage (NREM) of sleep. These neurons slow down as the brainwaves also reach a slower pattern. Other physical traits associated with the NREM sleep cycle often include; lower body temperature and slowed breathing. Within the NREM stage, the body undergoes three additional stages, N1-N3, and with each stage progression, the sleep quality increases. Researchers estimate that approximately 75% of sleep occurs in the NREM stages.
Benefits of Sleep ✅
Sleep is imperative to human development, especially in children. High-quality sleep greatly influences’ one’s overall demeanour.
Let’s face it, those often who refrain from getting a full night’s rest can be be generally unpleasant to be around. Regardless of one’s negative behaviour, the benefits from sleep also affect one’s physical health.
Importance of Sleep
- Enhances one’s memory and problem-solving skills
- Decreases the risk for sleep deprivation-related impairment
- Increases healthy immune functioning, which can limit the risk of viral infections
- Decreases the risk of cardiovascular diseases
- Provides REM cycle to your brain. (Which “deep cleans” the mind”s “junk files” so to speak.)
Clinical Testing for Sleep Quality
Now, how do researchers and doctors alike measure one’s quality of sleep?
From a clinical perspective, the most commonly used sleep performance evaluation occurs using a polysomnogram. In more simplistic terms, this test is known as an “asleep study.”
During the test, doctors monitor one’s blood oxygen levels, heart rate, breathing patterns and any limb movements.
Traditionally, polysomnograms are used as a diagnostic test to determine if the patient has one of the following conditions; narcolepsy, sleep apnea and insomnia. However, in the case of neurodivergents patients, sleep studies’ can detect any co-morbid conditions associated with one’s pre-existing neurodevelopmental condition diagnosis.
In addition to polysomnograms, physicians also measure sleep quality through actigraphy. This non-invasive test measures one’s activity level and rests over the desired time. The patient wears an actigraph on the wrist of the dominant hand. This device often provides doctors with data which is then applied with mathematical algorithms to determine patterns that occur while the patient is awake and asleep.
Sleep Neuroanatomy
The following structures in the human brain greatly contribute to the functionality of sleeping.
The Hypothalamus
This tiny structure hides deep inside the brain and encapsulates nerve cells that control sleep behaviours.
The hypothalamus is also home to the suprachiasmatic nucleus, this affects the information received by light exposure from the eyes. Patients with injuries in their SCN often lose their ability to identify light in their sleep cycle; therefore, they have more control to either wake-up or continue to sleep.
The Brain Stem
The brain stem acts as a communication medium to and from the hypothalamus.
The neurochemical GABA (γ-Aminobutyric acid) is produced from these two structures, which contribute towards reducing the activity of stimulation associated with arousal. Without the brain stem, we would not be able to “de-stress” in the form of muscle relaxation this is CRITICAL for the REM stage of sleep.
The Cerebral Cortex
Another important structure includes the cerebral cortex, which is responsible for long-term memory and information processing.
The thalamus helps transmits this information to the cerebral cortex. When your body enters the REM stage of sleep, the thalamus drives the images and other sensory effects that occur when we dream.
The Pineal Gland
The pineal gland works to receive signals from the suprachiasmatic nucleus (SCN) and leads to the production of melatonin. This hormone is created when your brain is exposed to darkness. Melatonin also aids in the timing of your circadian rhythm (your body’s 24 clocks).
Patients with vision loss commonly take melatonin supplements to support the lack of light that they don’t see.
The Basal Forebrain
The basal forebrain is located between the front and bottom parts of the brain.
The release of adenosine occurs from the cells in the basal forebrain and other parts of the brain. Adenosine is a chemical product of cellular energy. This increases your drive and need for sleep. Different drugs like caffeine counteract the production of adenosine which blocks feelings of sleepiness.
Autism & Sleep
What is Autism?
Autism Spectrum Disorder is a neurodevelopmental condition that is caused by abnormalities in the human brain. Neurodevelopmental impies that it is a part of you that was developed before you were even born.
Since autism is a spectrum, symptoms vary in severity from person to person. As an autistic person myself, I typically struggle with understanding social cues.
“As many as 80% of people with autism have trouble sleeping.”
Source — Sleepopolis
While, for the most part, the human brain seems to not differ from person to person, at least in a structural sense, this is proven incorrect for individuals with neurodevelopmental conditions.
In an article published by Dara Manoach, Ph.D. of Harvard Medical School, abnormalities within the sleep patterns of autistic individuals proved to be present from evidence found via neuroimaging. This is due to decreased function in the thalamocortical circuit.
What is the Thalamocortical Circuit?
In simple terms, this is the medium for communication between the eye and the cerebral cortex.
Solution?
As emerging technologies change the face of medicine, the intersection between physical devices and human organs regains its prevalence. In Dana Manoach’s research proposal surrounding understanding why autistic indivduals have thalamocortical circuit dysfunction, she utilizes brain-computer interface technologies.
“Because large-scale laboratory-based sleep studies are prohibitively expensive and burdensome, the first goal of this project is to validate the methodology and establish the feasibility of a large-scale at-home sleep study in ASD using a commercially available wearable electroencephalography (EEG) device.”
(SFARI | Characterizing Sleep Physiology in Autism: A Path From Genes to Treatment, n.d.).
What is an Electroencephalography (EEG) device?
The electroencephalography device is an electrogram that records brain activity.
Electrode sensors with miniature metal discs are attached to wires on top of the patient’s head. These sensors detect any changes in the electrical charges created by the movement of your neurons.
- Neurons = Brain Cells
All in a Night’s Rest
While the key to unlocking circadian rhythm differences between neurotypical and neurodivergent individuals is yet to be discovered. I feel that the solution lies within the depths of brain computational devices.
For those with similar excitement in this field, I have included links below to further your knowledge on this topic…
- My favourite BCI focused youtube channel, https://www.youtube.com/c/thebciguys
- Brain-Computer Interfaces in Medicine
- Clinical Integration of non-invasive BCIs
- What Brain-Computer Interfaces Could Mean for the Future of Work
- How to Control Things Using Your Brain (and Open-Source Hardware)
In other words, I look forward to investigating more within the field of computational neuroscience. If you have any questions or concerns, feel free to comment below!
My name is Lauren, and I’m an 18y/o passionate about making the world neuroinclusive ♾️ 🧠 through technology. Like what you see? Check out the rest of my digital footprint at https://linktr.ee/laurengp.
