of my GP saying to me:

"You are mentally sick

and you have to accept help to get better."

Hannah was a healthy 20-year-old psychology student

living at home with her family

when she started experiencing flu-like symptoms.

I went to my GP and I was kind of told

that viruses will just generally go,

you just need to go home and rest, take it easy.

Her GP thought she had glandular fever.

Hannah was feeling very tired, so the symptoms fitted.

But then she started to develop changes

in her personality.

Soon after, Hannah lost her ability to speak.

I had to ask my mum to come in,

sit with me and talk for me to the GP.

I would kind of write down to my mum

what needed to be said.

Hannah was sent home with antidepressants

and a referral to a psychologist.

Her symptoms deteriorated, and she was soon admitted

to a psychiatric hospital,

where she was given antipsychotic medication.

She was seen by a psychiatrist,

who ordered an MRI scan.

During the scan, doctors found a cyst on her brain

and sent her to A&E for investigation.

When I got to A&E,

they reviewed the cyst

and said I was probably born with it,

it probably had nothing to do with the symptoms.

But what they did notice was

that my blood test showed I was fighting

some sort of virus.

More tests followed,

and after three weeks, the results came back,

and Hannah finally got her diagnosis:

Anti-NMDA receptor encephalitis.

It's an autoimmune form of encephalitis,

which is the inflammation of the brain.

According to Professor Guy Leschziner,

having your physical symptoms mistaken for a mental illness

is not uncommon.

We do occasionally see individuals

with very severe psychosis and behavioural change

in whom the initial diagnosis

is of a psychotic illness like schizophrenia.

But actually,

over the course of days or weeks

whilst they're in hospital,

it begins to be obvious that actually

what is underlying their condition

is one of these autoimmune conditions.

It's been known for more than a century

that damage to particular parts of the brain

and things like tumours can result in changes

in personality or behaviour.

But over the last 20 years or so,

we've begun to recognise

that there are a number of conditions

that have an immune basis,

whereby the immune system attacks the brain

and causes changes

to the functioning of that brain.

In Hannah's case,

it took several weeks for doctors to recognise

that this was a serious autoimmune condition

that required treatment with very heavy-duty drugs.

I was moved to neurology ward.

I was completely mute

and I had lost the ability to dress myself,

wash myself, feed myself.

So I really was trapped in my own body at this stage.

Hannah underwent immunotherapy treatment

and had 13 plasma exchanges –

a process of filtering blood

before pumping it back into her body.

Although the treatment didn't work initially,

and her parents were told by doctors

she probably didn't have long to live,

after two weeks, Hannah woke up.

Hannah, say "Dad".

Dad.

Over subsequent weeks,

she learnt to speak again and walk again.

She says it was like learning how to live again.

I look back at the person

before I got encephalitis,

and I don't really know her.

I just can't connect with that person.

Five years on, Hannah has mostly recovered,

though she is still on immunotherapy treatment,

and that makes her more vulnerable to infections

and could impact her fertility.

I wish GPs would know more about encephalitis,

because they're the first point of contact

for a lot of patients.

I wish my GP knew more about it,

so she could direct me to the right pathway.

If I was to think about all the people who had encephalitis

and died in psychiatric hospitals

or care homes,

I wouldn't be able to sleep at night.

In Hannah's case,

a physical illness, encephalitis, was mistaken

for mental illness.

But sometimes it's the other way around.

We know that the connection

between body and mind goes both ways.

Physical problems can result in psychiatric symptoms,

but also psychological issues

can contribute to physical disease.

Professor Leschziner says he sees patients

who have symptoms like seizures, paralysis

and numbness with no obvious physical cause.

Some are eventually diagnosed

as having functional neurological disorder,

or FND,

which is a problem with how the brain receives

and sends information to the rest of the body.

We don't fully understand

what causes these conditions.

It seems that anybody can be vulnerable to changes

within the software that defines

how our nervous systems work.

We know that there are some risk factors.

So stress, anxiety, depression,

previous psychological trauma in particular.

But ultimately,

anybody can develop

these functional neurological disorders.

Globally, hundreds of thousands of people

develop FND every year.

Conditions like FND

and the experiences of people like Hannah

have led some doctors to believe that we need

to stop thinking of mental and physical health

as separate.

I think we need to move away

from defining diseases or disorders

as of the body and of the mind.

We know that actually, in almost all cases,

there are contributions from both.

Even in conditions that are thought to have

a pure physical basis,

we know that how people interpret their symptoms

is important in terms of defining their quality of life

and how severe they perceive their symptoms to be.

So actually understanding that,

making sure that everybody has access

to both physical and psychological treatments

is really of utmost importance

for pretty much every condition that is seen

by our healthcare systems,

and is important for everyone.