Have you ever found yourself searching for a word you should know, forgetting what you were just doing, or feeling mentally foggy for no obvious reason?

These everyday lapses are common and are most often a normal part of life, or a sign we might be tired or stressed. But for some people, they could be early signs of a rare condition called autoimmune encephalitis. This is when the body’s own immune system mistakenly attacks the brain and causes inflammation and swelling.

It can happen suddenly and at any age. Sometimes it follows a viral infection, but in many cases, the exact cause is unknown.

Autoimmune encephalitis is rare, affecting up to roughly 14 people in 100,000 each year. However, as awareness and testing improve, doctors are realising it’s more common than once thought.

So, what are the signs of autoimmune encephalitis, and how is it treated?

Autoimmune encephalitis causes inflammation that disrupts normal brain function, affecting how people think, remember and process information.

The inflammation often begins in the limbic system – the part of the brain that regulates emotions and forms memories. From there, inflammation can spread along connected brain networks, disrupting attention, language and planning.

Symptoms can range from striking changes – such as seizures, personality changes and hallucinations – to subtler difficulties, including confusion, forgetfulness, trouble focusing and feeling mentally slower.

These changes may come and go, or seem like stress or fatigue. Over time, they can make everyday life significantly more difficult.

As symptoms are not always visible, they are easily overlooked, resulting in delays or........

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