Pratik Raul, University of Canberra; Jeroen van Boxtel, University of Canberra, and Jovana Acevska, University of Canberra

Autism is a neurodevelopmental difference associated with specific experiences and characteristics.

For decades, autism research has focused on behavioural, cognitive, social and communication difficulties. These studies highlighted how autistic people face issues with everyday tasks that allistic (meaning non-autistic) people do not. Some difficulties may include recognising emotions or social cues.

But some research, including our own study, has explored specific advantages in autism. Studies have shown that in some cognitive tasks, autistic people perform better than allistic people. Autistic people may have greater success in identifying a simple shape embedded within a more complex design, arranging blocks of different shapes and colours, or spotting an object within a cluttered visual environment (similar to Where’s Wally?). Such enhanced performance has been recorded in babies as young as nine months who show emerging signs of autism.

How and why do autistic individuals do so well on these tasks? The answer may be surprising: more “neural noise”.

What is neural noise?

Generally, when you think of noise, you probably think of auditory noise, the ups and downs in the amplitude of sound frequencies we hear.

A similar thing happens in the brain with random fluctuations in neural activity. This is called neural noise.

This noise is always present, and comes on top of any brain activity caused by things we see, hear, smell and touch. This means that in the brain, an identical stimulus that is presented multiple times won’t cause exactly the same activity. Sometimes the brain is more active, sometimes less. In fact, even the response to a single stimulus or event will fluctuate continuously.

Neural noise in autism

There are many sources of neural noise in the brain. These include how the neurons become excited and calm again, changes in attention and arousal levels, and biochemical processes at the cellular level, among others. An allistic brain has mechanisms to manage and use this noise. For instance, cells in the hippocampus (the brain’s memory system) can make use of neural noise to enhance memory encoding and recall.

Evidence for high neural noise in autism can be seen in electroencephalography (EEG) recordings, where increased levels of neural fluctuations were observed in autistic children. This means their neural activity is less predictable, showing a wider range of activity (higher ups and downs) in response to the same stimulus.

In simple terms, if we imagine the EEG responses like a sound wave, we would expect to see small ups and downs (amplitude) in allistic brains each time they encounter a stimulus. But autistic brains seem to show bigger ups and downs, demonstrating greater amplitude of neural noise.

Many studies have linked this noisy autistic brain with cognitive, social and behavioural difficulties.

But could noise be a bonus?

The diagnosis of autism has a long clinical history. A shift from the medical to a more social model has also seen advocacy for it to be reframed as a difference, rather than a disorder or deficit. This change has also entered autism research. Neuroaffirming research can examine the uniqueness and strengths of neurodivergence.

Psychology and perception researcher David Simmons and colleagues at the University of Glasgow were the first to suggest that while high neural noise is generally a disadvantage in autism, it can sometimes provide benefits due to a phenomenon called stochastic resonance. This is where optimal amounts of noise can enhance performance. In line with this theory, high neural noise in the autistic brain might enhance performance for some cognitive tasks.

Our 2023 research explores this idea. We recruited participants from the general population and investigated their performance on letter-detection tasks. At the same time, we measured their level of autistic traits.

We performed two letter-detection experiments (one in a lab and one online) where participants had to identify a letter when displayed among background visual static of various intensities.

By using the static, we added additional visual noise to the neural noise already present in our participants’ brains. We hypothesised the visual noise would push participants with low internal brain noise (or low autistic traits) to perform better (as suggested by previous research on stochastic resonance). The more interesting prediction was that noise would not help individuals who already had a lot of brain noise (that is, those with high autistic traits), because their own neural noise already ensured optimal performance.

Indeed, one of our experiments showed people with high neural noise (high autistic traits) did not benefit from additional noise. Moreover, they showed superior performance (greater accuracy) relative to people with low neural noise when the added visual static was low. This suggests their own neural noise already caused a natural stochastic resonance effect, resulting in better performance.

It is important to note we did not include clinically diagnosed autistic participants, but overall, we showed the theory of enhanced performance due to stochastic resonance in autism has merits.

Why this is important?

Autistic people face ignorance, prejudice and discrimination that can harm wellbeing. Poor mental and physical health, reduced social connections and increased “camouflaging” of autistic traits are some of the negative impacts that autistic people face.

So, research underlining and investigating the strengths inherent in autism can help reduce stigma, allow autistic people to be themselves and acknowledge autistic people do not require “fixing”.

The autistic brain is different. It comes with limitations, but it also has its strengths.

Pratik Raul, PhD candidiate, University of Canberra; Jeroen van Boxtel, Associate professor, University of Canberra, and Jovana Acevska, Honours Graduate Student, University of Canberra

This article is republished from The Conversation under a Creative Commons license. Read the original article.

“What are the main factors in forming someone’s personality?” – Emma, age 10, from Shanghai

Hello Emma, and thank you for this very interesting question!

Let’s start by exploring what we mean by personality. Have you noticed no two people are completely alike? We all see, experience, and understand the world in different ways.

For example, some people love spending time with friends and being the centre of attention, whereas other people are more shy and enjoy having time to themselves.

Your unique personality is shaped by your genes as well as various influences in your environment. And your personality plays an important role in how you interact with the world.

The big five

Did you know there are scientists who spend time researching personality? Their research is concerned with describing the ways people differ from each other, and understanding how these differences could be important for other parts of life such as our health and how well we do in school or at work.

There are many different perspectives on personality. A widely accepted viewpoint based on a lot of research is called the five factor model or the “big five”. According to this theory, a great deal of a person’s personality can be summarised in terms of where they sit on five dimensions, called traits:

1. the introversion-extraversion trait refers to how much someone is outgoing and social (extroverted) or prefers being with smaller groups of friends or focusing on their own thoughts (introverted)
2. agreeableness captures how much someone tends to be cooperative and helps others
3. openness to experience refers to how much a person is creative and enjoys experiencing new things
4. neuroticism describes a person’s tendency to experience negative feelings, like worrying about things that could go wrong
5. conscientiousness encompasses how much a person is organised, responsible, and dedicated to things that are important to them, like schoolwork or training for a sports team.

A person can have high, low, or moderate levels of each of these traits. And understanding whether someone has higher or lower levels of the big five can tell us a lot about how we might expect them to behave in different situations.

So what shapes our personalities?

A number of factors shape our personalities, including our genes and social environment.

Our bodies are made up of many very small structures called cells. Within these cells are genes. We inherit genes from our parents, and they carry the information needed to make our bodies and personalities. So, your personality may be a bit like your parents’ personalities. For example, if you’re an outgoing sort of person who loves to meet new people, perhaps one or both of your parents are very social too.

Personalities are also affected by our environment, such as our experiences and our relationships with family and friends. For example, some research has shown our relationships with our parents can influence our personality. If we have loving and warm relationships, we may be more agreeable and open. But if our relationships are hurtful or stressful, this may increase our neuroticism.

Another study showed that, over time, young children who were more physically active were less introverted (less shy) and less likely to get very upset when things don’t go their way, compared to children who were less physically active. Although we don’t know why this is for sure, one possible explanation is that playing sport leads to reduced shyness because it introduces children to different people.

While we’re learning more about personality development all the time, research in this area presents quite a few challenges. Many different biological, cultural and environmental influences shape our development, and these factors can interact with each other in complex ways.

Is our personality fixed once we become adults?

Although we develop most of our personality when we are young, and people’s personalities tend to become more stable as they get older, it is possible for aspects of a person’s personality to change, even when they are fully grown.

A good example of this can be seen among people who seek treatment for conditions like anxiety or depression. People who respond well to working with a psychologist can show decreases in neuroticism, indicating they become less likely to worry a lot or feel strong negative feelings when something stressful happens.

Hello, Curious Kids! Do you have a question you’d like an expert to answer? Ask an adult to send your question to mailto:curiouskids@theconversation.edu.au

Tim Windsor, Professor, Director, Generations Research Initiative, College of Education, Psychology and Social Work, Flinders University and Natalie Goulter, Lecturer, College of Education, Psychology and Social Work, Flinders University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Last week, the Australian Therapeutic Goods Administration added intravenous (IV) fluids to the growing list of medicines in short supply. The shortage is due to higher-than-expected demand and manufacturing issues.

Two particular IV fluids are affected: saline and compound sodium lactate (also called Hartmann’s solution). Both fluids are made with salts.

There are IV fluids that use other components, such as sugar, rather than salt. But instead of switching patients to those fluids, the government has chosen to approve salt-based solutions by other overseas brands.

So why do IV fluids contain different chemicals? And why can’t they just be interchanged when one runs low?

We can’t just inject water into a vein

Drugs are always injected into veins in a water-based solution. But we can’t do this with pure water, we need to add other chemicals. That’s because of a scientific principle called osmosis.

Osmosis occurs when water moves rapidly in and out of the cells in the blood stream, in response to changes to the concentration of chemicals dissolved in the blood plasma. Think salts, sugars, nutrients, drugs and proteins.

Too high a concentration of chemicals and protein in your blood stream leads it to being in a “hypertonic” state, which causes your blood cells to shrink. Not enough chemicals and proteins in your blood stream causes your blood cells to expand. Just the right amount is called “isotonic”.

Mixing the drug with the right amount of chemicals, via an injection or infusion, ensures the concentration inside the syringe or IV bag remains close to isotonic.

What are the different types of IV fluids?

There are a range of IV fluids available to administer drugs. The two most popular are:

• 0.9% saline, which is an isotonic solution of table salt. This is one of the IV fluids in short supply
• a 5% solution of the sugar glucose/dextrose. This fluid is not in short supply.

There are also IV fluids that combine both saline and glucose, and IV fluids that have other salts:

• Ringer’s solution is an IV fluid which has sodium, potassium and calcium salts
• Plasma-Lyte has different sodium salts, as well as magnesium
• Hartmann’s solution (compound sodium lactate) contains a range of different salts. It is generally used to treat a condition called metabolic acidosis, where patients have increased acid in their blood stream. This is in short supply.

What if you use the wrong solution?

Some drugs are only stable in specific IV fluids, for instance, only in salt-based IV fluids or only in glucose.

Putting a drug into the wrong IV fluid can potentially cause the drug to “crash out” of the solution, meaning patients won’t get the full dose.

Or it could cause the drug to decompose: not only will it not work, but it could also cause serious side effects.

An example of where a drug can be transformed into something toxic is the cancer chemotherapy drug cisplatin. When administered in saline it is safe, but administration in pure glucose can cause life-threatening damage to a patients’ kidneys.

What can hospitals use instead?

The IV fluids in short supply are saline and Hartmann’s solution. They are provided by three approved Australian suppliers: Baxter Healthcare, B.Braun and Fresenius Kabi.

The government’s solution to this is to approve multiple overseas-registered alternative saline brands, which they are allowed to do under current legislation without it going through the normal Australian quality checks and approval process. They will have received approval in their country of manufacture.

The government is taking this approach because it may not be effective or safe to formulate medicines that are meant to be in saline into different IV fluids. And we don’t have sufficient capacity to manufacture saline IV fluids here in Australia.

The Australian Society of Hospital Pharmacists provides guidance to other health staff about what drugs have to go with which IV fluids in their Australian Injectable Drugs Handbook. If there is a shortage of saline or Hartmann’s solution, and shipments of other overseas brands have not arrived, this guidance can be used to select another appropriate IV fluid.

Why don’t we make it locally?

The current shortage of IV fluids is just another example of the problems Australia faces when it is almost completely reliant on its critical medicines from overseas manufacturers.

Fortunately, we have workarounds to address the current shortage. But Australia is likely to face ongoing shortages, not only for IV fluids but for any medicines that we rely on overseas manufacturers to produce. Shortages like this put Australian lives at risk.

In the past both myself, and others, have called for the federal government to develop or back the development of medicines manufacturing in Australia. This could involve manufacturing off-patent medicines with an emphasis on those medicines most used in Australia.

Not only would this create stable, high technology jobs in Australia, it would also contribute to our economy and make us less susceptible to future global drug supply problems.

Nial Wheate, Professor and Director Academic Excellence, Macquarie University and Shoohb Alassadi, Casual academic, pharmaceutical sciences, University of Sydney

This article is republished from The Conversation under a Creative Commons license. Read the original article.