Inside the Autistic Brain

Greetings Earthlings! 🙂

Today I’m going to dive into the physiology of the autistic brain to explain what’s actually going on at the neurological level. I’ve touched on aspects of the science in previous posts, but I wanted to give you a quick overview post where the main points in the one place 🙂

So let’s get down to some science! 🙂

Hyper-connected Neurons:

Scientific evidence suggests that neurons in the autistic brain are hyper-connected. Specifically, studies indicate that autists have too many synapses in the brain. The synapse is basically a gap or a junction between two neurons where chemical messengers (neurotransmitters) carry information like a ferry from one neuron to the next. It looks a little bit like this:

Image result for synapse

During normal brain development, about half of the synapses we are born with are “pruned” off. In autism, this process is slowed down, and so autistic children have an excessive amount of synapses compared with their neurotypical peers. As these connections are essential to communication between neurons, this can greatly effect how the brain works and processes information.

Dysfunction at the Junction:

In addition to possessing an excessive number of synapses, communication at these neuronal junctions is also impaired in the autistic brain.

Animal studies have indicated that synapses function differently in the autistic brain as a result of genetic mutation. Mutations cause certain proteins to be absent in autism- proteins that are essential to the normal functioning of the synapse. As a consequence of this, the transmission of information between neurons is affected, resulting in a number of social and behavioral issues.

Think of physical junctions on a busy road- if something goes wrong at the junction, a chain of chaos will ensue!

Image result for junction crash gif

Hyper-excitable Neurons:

Research shows that in many cases of autism, neurons in certain regions of the brain are more excitable than others. This means that these neurons are more sensitive to stimulation. For example, the neurons located in the sensory cortex of the brain (which processes sensory information such as smell), are more sensitive and excitable than other neurons. This is kind of like how a person can be more ticklish in some parts of the body than another- the nerves in the underarm are more excitable than those of the arm.

This sensitizes the autistic brain to all kinds of stimuli as discussed here.

Dysregulated Neurotransmitter levels:

As previously mentioned, information travels across the synapses in the brain via chemical messengers known as neurotransmitters. In the autistic brain, the levels of these neurotransmitters are dysregulated- or out of sync. Research indicates that individuals with autism tend to have higher levels of excitatory neurotransmitters (e.g. glutamic acid) and lower levels of calming neurotransmitters (e.g. GABA, serotonin) causing neurons in the autistic brain to fire excessively. In addition to this, levels of the neurohormone (a chemical that acts as both a hormone and neurotransmitter) oxytocin, which plays an influential role in trust and social behaviours, are also out of balance. Moreover, dopamine (a neurotransmitter which can both calm and excite) is also dysregulated in autism. Together, the action of biochemicals like these influences a number of autistic behaviours and issues such as ADHD, mood, appetite, sleep, anxiety, sensory processing, social behaviours, learning, memory and emotional responses.

Male vs Female Brain

Perhaps one of the most fascinating things that I have discovered about autism are the anatomical differences between the brains of the male and female autist. Brain imaging studies have revealed that autistic women have brains that are anatomically similar to neurotypical male brains, and the brains of male autists share anatomical similarities to those of neurotypical female brains.

In short- this indicates that men with autism have feminine brains, and women with autism have masculine brains!!!

I know!!!!

It sounds weird, but it makes a world of sense. Oftentimes I’ve felt like I had a male brain growing up- my tomboyish interests, my fashion sense, my preference for male company, my inability to walk in heels; it all fits!

Strange but true! 🙂

There we have it Earthlings- hope you enjoyed this brief insight into the physiology of the autistic brain 🙂 There is no clear mechanism through which autism acts, these are just some of the likely pathways involved. I’ll explore other possible mechanisms in a later post.

Have a good week everyone! 🙂

Aoife

April 10, 2017 20

Autism and Textures

Greetings Earthlings! 🙂

Today I’m going to talk about something that you may not be aware of in relation to autism- the issue of texture sensitivity.

During my assessment, I was asked by the psychologist if I had any issues with textures. Caught off guard (as I was unwittingly hoodwinked into attending the assessment 😛 ), I quickly answered no, only to realize hours later that in actual fact, textures influence my life hugely!

In all previous conversations about autism, I had never heard anything about textures, but these are in actual fact a common source of sensitivity for autists.

Rough seat belts, itchy labels and materials, even bras can be extremely irritating to the hypersensitive autist.

There was absolute war between my mother and I when I would refuse to wear a bra as a child! The sensation of the garment against my skin weirded me out and I found it extremely uncomfortable. I would even try wearing it over my thermal vest to place a barrier between me and it, buuuut it didn’t very work well…I was constantly fidgeting! 😛

Weird textures completely freak me out- cornflour (a particular pet peeve), some fruits and veg, yogurts (or most foods) with lumps in them and nail files to name but a few.

Encounters with such textures can lead to reactions like these…:

(Fun fact about me- I genuinely shake my head like a dog when I shudder! 😛 )

It’s not all negative though- you can learn to adapt and condition yourself to stimuli 🙂 I never drank a glass of water until I was 11 years old as it felt really weird to me compared with other more flavorful drinks. I gradually conditioned myself to it by taking one gulp water followed by one gulp juice (my family found this hilarious 😛 ) until the glass was empty- I now drink pints of water daily without issue! 🙂

Pleasant textures on the other hand pose an entirely different sensory experience, lighting up my brain like a Christmas tree! 🙂

The creamy texture of ice cream or chocolate melting in my mouth, the strangely irresistible and soothing feel of metal against my skin or the drug-like euphoria that comes from stroking a fluffy puppy-sheer bliss! 🙂

As my sister remarked as I was writing this piece, it’s easier to list the textures that I do like than those I don’t! 🙂 😉

So what’s the scientific reason for this sensitivity?

As we have discussed in previous posts (Autism 101-Sensory Processing;Discussion-Trust, Intimacy and Sexuality), people with autism are hypersensitive to the sensation of touch. Dysfunctions in brain areas involved in sensory integration, in addition to hyper-connected and hyper-excitable neurons within the autistic brain, can greatly influence our responses to texture.

MRI studies of autistic brains also suggest that there is an exaggerated response to unpleasant stimuli in particular within the limbic system- a set of structures involved in such processes as emotions, behaviours and motivation.

It may seem like we’re consciously overreacting to certain textures, but our response is entirely neurological- so try to keep that in mind next time you see us pull a weird face after encountering an unpleasant texture! 😛 😉

Image result for nasty taste gif

Have a good week everyone! 🙂

Aoife

March 13, 2017 12

Autism on Screen- My Name Is Khan

Greetings Earthlings! 🙂

In the next part of my autism on screen series, I’m going to explore the portrayal of autism in the Indian drama film ‘My Name Is Khan‘ (2010).

My Name Is Khan film poster.jpg

A dual Hindi and English language film, ‘My Name Is Khan‘ follows Rizwan Khan, a Muslim man with Asperger’s syndrome, who set’s out on a journey across America to tell the president that he is not a terrorist following a sectarian attack on his family in the wake of the events of 9/11.

Check out the trailer below! 🙂

So how does this film measure up in it’s portrayal of the realities of AS?

The film opens with a disclaimer stating that the film makers have endeavored to depict AS as authentically and sensitively as possible, however, as this is a work of fiction, they acknowledge that certain creative liberties were taken in the portrayal of autism- so as with ‘Rain Man‘, take the film with a grain of salt!

That being said, I found this film to be generally quite accurate from a symptomatic perspective. Granted, Khan appears slightly weirder than the average person with AS and many of his symptoms are exaggerated, but overall I felt that this was a solid onscreen portrayal of autism.

In particular I felt that this film gave a good representation of repetitive behaviors and sensory sensitivity.

Throughout the film, Khan can be seen fiddling with some stones in a repetitive manner.

autism stones my name is khan aspergers syndrome repetitive behvaiour

I may not carry stones around with me, but I am constantly fiddling with my jewelry in a similar manner. It’s a compulsive action- I have this constant need to reach out and feel my chain between my fingers. There’s something incredibly soothing about the motion, especially when you’re particularly stressed. Actions such as these are referred to as stimming or self stimulation. I’ll dedicate a post to stimming at another stage 🙂

As regards sensory sensitivity, I thought that the film presented more of a normalized and subtle reaction to sensory stimuli than most films featuring autism, particularly in relation to Khan’s sensitivity to the colour yellow (there’s a particularly funny moment where he changes direction on the street to avoid looking at someone wearing a yellow top!).

yellow my name is khan

When I first watched this film, I thought that this had to be an exaggeration, but in actual fact, as I mentioned in the last post, boys with autism really struggle to process the colour yellow! Scientists think that this may result from a sensitivity to luminance in autists. Alternatively this may occur as yellow is one of the most heavily sensory loaded colours, as it engages multiple colour detection cells (called cones) in the eye.

Comparing this film to ‘Rain Man‘, there is quite a difference in how autism is portrayed. There was a far greater focus on everything that is good about Khan rather than areas of disability in his life, which can often be exploited in film for dramatic effect. Unlike ‘Rain Man‘, modern films about autism, such as this, have the added benefit of over twenty years of research and observation of the autistic condition, leading to more accurate depictions/attitudes to difference on screen.

Unfortunately however, Khan is depicted as quite intelligent (even called a genius), with superb memory and a savant-like ability to fix any mechanical item known to man, further promoting the stereotype of the autistic savant. These traits however, are somewhat muted in comparison to ‘Rain Man‘, giving a slightly more realistic portrayal of autism.

So there we are- hope you all enjoyed this piece 🙂 I would highly encourage you all to watch this film at some stage. Autism aside, this is an amazing film- one of the best I’ve seen in a long time! In the latter half of the film, you start to forget that Khan is in any way different, finding yourself swept up in this powerful story of love, loss and acceptance. Having watched only the trailer to re-jog my memory, I really want to see this film again myself! 😀

Weekend plans sorted! 😉

Aoife

March 3, 2017 2

Autism 101-Sensory Processing

Greetings Earthlings! 🙂

So today I’m going to briefly introduce you to the issue of sensory processing for people on the spectrum. This is a very broad topic, but I’ll expand on the issues in more detail at a later stage 🙂

Many individuals on the autistic spectrum struggle to process every day sensory information. Sounds, textures, smells, lights, even colours (boys in particular struggle to process the colour yellow) can overload the nervous system and greatly upset us, effect our behavior or even trigger a meltdown.

But why?

In autism, our senses can be either hyper or hypo sensitive (sometimes even both) to stimuli at different times. Our senses are heightened- smells are stronger, sounds are louder. As a result of this, stimuli reverberate all the more intensely in our brains.

Think of the brain as a computer server at exam time where everyone is logging in at once. Too much information has been entered into the system, but the server can only cope with so much. The entire system becomes overwhelmed and the server crashes.

Here’s just a quick video simulation of sensory overload.

Warning for those on the spectrum– this video contains flashing lights, bright colours and loud, sudden noises

For me personally, I have many (mild) issues with sensory processing. Smells, tastes and textures are a daily struggle. For example, I don’t think I’ll ever be able to eat a salad as the smell alone makes me want to throw up- I’m dreading what pregnancy may one day bring! 😛 😉

Loud or irritating noises, (especially repetitive ones), too can be a challenge. Don’t get me started on the shock I get when a passing bus makes that giant hiss/woosh sound or a car honks the horn unexpectedly!! 😛

Most days, you’re lucky and the offending stimulus passes quickly, but other times it can get the better of you. I recently had a near meltdown on holiday from a cocktail of excessive heat, hunger, exhaustion and social frustration.

Top Tip– Keep on top of your hunger/thirst. I’ve discovered this past year that an excess of either will make me act really loopy! 😛

When you’re hit by sensory overload, it feels as though your head is caught in a vice grip. Your mind is screaming, unable to focus on anything else but the source of discomfort.

The worst part of it I find is coming across as a complete basket case when overloaded. You don’t get the most sympathetic of looks when you complain about a persistent noise- few can understand how it’s making your brain hurt.

So what does science have to say about sensory processing?

Sensory integration involves three basic sensory systems:

The tactile system (touch)- comprises a series of nerves passing information from the skin to the brain
The vestibular system (sound)- comprises a series of structures in the inner ear involved in movement detection
The proprioceptive system-a series of receptors in the muscle (proprioreceptors) which feed information to the brain about the body’s position

These three systems share a close but complicated relationship which allow us to experience, process and respond to different stimuli. Dysfunction in this network can cause hyper/hypo sensitivity, in addition to problems with coordination, behavior and academic issues.

Evidence from brain imaging studies has also shown that autists experience stronger responses in the brain to sensory stimuli in areas that process sensory information and the amygdala- an area that is involved in attention, emotional reactions and threat response.

But why is this?

Several studies have found evidence of hyper-excitability and hyper-connectivity in the autistic brain.

Evidence shows that in many cases of autism, the neurons located in the sensory cortex of the brain are more sensitive and excitable than others. This is kind of like how a person can be more ticklish in some parts of the body than another- the nerves in the underarm are more excitable than those of the arm.

The autistic brain has also shown signs of hyper-connectivity, where regions of the brain are excessively connected- like an overloaded plug!

This amplifies memory formation, sensory processing and causes an autist to be hyper-emotional, which can make the world painfully intense. Scientists have theorized that autists prefer safe, controlled and predictable environments as a coping mechanism to actively avoid this pain.

Finally, studies have indicated that sensory issues, in addition to a number of other autistic behaviors, may be linked to neurotransmitter (chemical messengers between body and brain) levels in the body. As previously discussed, some neurotransmitters are dysregulated in autism. Evidence suggests that in cases of autism, there are higher levels of excitatory neurotransmitters, and lower levels of inhibitory (i.e. calming) neurotransmitters. These high levels of excitatory neurotransmitters cause neurons to fire excessively, which can influence sensory perception and processing.

I’ll expand a little bit more on the individual sensory issues at a later stage 🙂

Enjoy your week everyone 🙂

Aoife

February 27, 2017 42

Tag: sensory processing

Inside the Autistic Brain

Autism and Textures

Autism on Screen- My Name Is Khan

A Is For Aoife Not Autism