The 10 subtle signs you could have an undiagnosed brain disease

Top psychiatrists have revealed 10 subtle signs you could have an increasingly common brain disorder. 

It is estimated that more than 22 million children and adults in the US have ADHD - up from around 14 million in 2015. 

The condition - which is thought to be caused by a variety of factors, including the slower development of key brain areas - can be difficult to diagnose, especially in adults, as certain symptoms are similar to those caused by other conditions like anxiety or mood disorders.

It is usually characterized by inattention, hyperactivity, and impulsivity, but experts in the field say there are other traits you can look for before seeking an official diagnosis.

These subtle signs can present themselves in both adults and children before and after they are diagnosed, although medication can help lessen these. 

Dr Dede O'Shea, a neuropsychologist at Beth Israel Lahey Health in Cambridge, Massachusetts, says one of the more subtle signs that often gets overlooked is procrastinating 'to the extreme'.

The ADHD Centre, based out of the UK, says people with the condition often struggle with chronic procrastination because the condition makes things, such as time management, memory, self-control, and multi-tasking, extremely difficult.

Therefore, consistently delaying tasks at work or at home becomes a form of coping with ADHD. 

O'Shea told the HuffPost: 'The average person might feel bored by a routine task, but with ADHD, the negative feeling is more extreme - and so, too, the avoidance of it.'

She added: 'It can be missed as a potential ADHD symptom because it looks like intentional laziness and lack of motivation.' 

The ADHD Centre says chronic procrastination can lead to problems in the workplace and at home, and it can also take an emotional toll, with feelings of shame, guilt or frustration stemming from not being able to complete simple tasks.

While it can be difficult for people with ADHD to start a task, O'Shea says once they do start, they can often find themselves hyperfocusing on it.

She explains: 'Hyperfocus is a symptom that can easily be missed because it looks like the person is only motivated to do certain activities. It's sometimes mistaken as selfishness and overzealousness.'

The Attention Deficit Association says that hyperfocus likely happens due to the way the ADHD brain is wired.

It notes: 'A deficiency in dopamine, a chemical messenger of the brain, changes how the ADHD brain perceives reward and manages attention.

'As a result, managing your attention can be more difficult, making it easier to slip into hyperfocus.'

Another lesser-known symptom of undiagnosed ADHD is an out-of-control shopping habit. 

Experts say impulsive spending could be another sign of ADHD as the disorder impacts impulse control. 

Studies have indicated that, on average, ADHD-related impulse spending costs individuals around $2,000 per year.

Dr Mareen Dennis, a psychological practitioner with the University of Kentucky Department of Psychiatry, says some of the things people with ADHD can do to prevent impulse spending include using cash only in stores and deleting card and other payment information from online stores.

Running late all the time could be another subtle indicator you have ADHD, as the condition makes it trickier to keep track of time and focus on getting ready within a certain time frame. 

Explaining how 'time blindness' might present itself, O'Shea says: 'You might know the exact time of an appointment, but leave the house at that time rather than in advance to give yourself room to travel there, park and sign yourself in.'

If you suddenly find yourself flying into a rage over a small thing, the experts say this too could be a symptom of ADHD, as the condition makes it difficult to regulate emotions. 

This, O'Shea notes, is related to the difficulties that can come with managing attention and directing energy.

Regarding the extreme ADHD emotional mood swings, the Attention Deficit Association says: 'Imagine if traffic lights skipped yellow and went straight from green to red without warning - driving under these conditions would be very stressful.

'If you have ADHD, handling your emotions might feel a bit like this. You may be calm and happy one moment. Then, without any warning, a small trigger can flip your emotions from green to red.'

Forgetting to eat isn't just because the workday is busy, it could also be a sign of ADHD. 

The experts highlight ADHD is often linked to abnormal eating patterns because of the inability to plan time well and keep focused on tasks.  

However, binge eating - when you uncontrollably eat a large amount of food in a short amount of time - is most commonly associated with the condition. 

Duke University estimates about 30 percent of adults with binge eating disorder, also have a history of ADHD. 

Dr Roberto Olivardia, a clinical psychologist who specializes in the treatment of ADHD and eating disorders, says many individuals with the condition are on a 'see food diet... If they see it, they eat it.'

To overcome this, he suggests portioning meals in advance and practicing mindfulness while eating so you know when to stop when full.  

Sleep disorders are also linked to ADHD, and the Sleep Foundation reveals that children with the neurological condition are also more likely to experience nightmares. 

They say that ADHD-related sleep problems such as insomnia may be 'a side effect of impaired arousal, alertness, and regulation circuits in the brain'. 

Although some studies have suggested that these problems can also be 'traced to a delayed circadian rhythm with a later onset of melatonin production (the sleep hormone).'

On a similar theme, constant restlessness or fidgeting is something experts say to watch out for. 

O'Shea added: 'Adults [with ADHD] are more likely to show restlessness through having to get up and pace around.

'They might not be able to sit through a movie without talking or getting out their phone.' 

The restlessness caused by ADHD might also make it more difficult to make decisions. 

While some decisions might be impulsive, others might need more time to process.  

Touching on why this happens, O'Shea says: 'This is a result of controlling attention well enough to sort through the pros and cons of a decision and remember what you were thinking.'

Moving to the final subtle sign, the experts say it is important to reflect on how you communicate with others, as this could be an indicator of your brain health. 

Due to increased impulsivity and a lack of ability to regulate emotions, ADHD can make communicating difficult. 

Patients might have difficulties focusing on conversations, actively listening, staying on topic and remembering details discussed. 

They might also cause offense by interrupting others, speaking before thinking and making regretful statements as their emotions get the better of them. 

If you're diagnosed with ADHD, the condition can be managed to decrease the severity of symptoms. Many people use medication to help deal with the side effects, with the recommended drugs including stimulants and non-stimulants. 

Healthcare providers often prescribe antidepressants, as well.