"My life is awful." Sarah tells her therapist. "I hate school. My parents have grounded me." The therapist beeps: "You need to go to the human repair shop. There you will be rewired and have new batteries installed. Next please!"

This is a comic vision of how a human being might talk to an AIA computer programme that has been designed to think.  therapistA person who helps someone with emotional or physical difficulties, often through talking to them. . But for many people the subject has become very serious.

Just over a year ago, a student called Sam Zaia came up with a chatbot called Psychologist. It has now received 78 million messages. It is visited by 3.5 million people a day.¹

"So many people who've messaged me say they access it when their thoughts get hard, like at 2am when they can't really talk to any friends or a real therapist," Sam says. He adds that for many young people, texting feels easier than talking to someone.

Two other popular therapy chatbots are Earkick and Woebot. Earkick's creators say users' moods improve by 34% within five months.

In the UK, some NHSThe National Health Service, the publicly funded healthcare system in the UK. The NHS was founded in 1948. trusts are already using a chatbot called Limbic Access. The company claims it is 93% accurate in classifying the most common mental health problems.²

AI is being put to other clever uses. One is aimed at people who hear voices: it allows them to create an avatarAn icon or figure representing someone online. they can argue against. Another uses virtual reality to help with problems like fear of heights.

Experts say none of these can stand in for real therapists. Therapy depends on human interaction, trust and emotional intelligence.

One psychotherapistSomeone who treats emotional problems and mental health issues. There are over 1,000 types of psychotherapy., Dr Emma Byrne, warns that patients can start to think of chatbots as real people. They become attached to something that seems intelligent "but has no empathyThe capacity to understand and feel the suffering of others., no understanding of what it is to be human... It is the most dangerous friend you could have if you are feeling low, self-destructive or likely to do something dangerous."

Yes: Chatbots can be taught to ask questions, but they cannot actually understand the problems presented to them. Only a properly trained fellow human can get to the bottom of someone's difficulties.

No: All humans have flaws which can prevent them from giving the best treatment. They may not have sufficient sympathy for their patients or be stuck in their ways and blind to alternative solutions.

Or... Chatbots could relieve a therapist of basic tasks, allowing him or her to focus on the hardest part of the job. With them, more people could access mental health care cheaply and when they need it.

AI - A computer programme that has been designed to think. 

Therapist - A person who helps someone with emotional or physical difficulties, often through talking to them.

NHS - The National Health Service, the publicly funded healthcare system in the UK. The NHS was founded in 1948.

Avatar - An icon or figure representing someone online.

Psychotherapist - Someone who treats emotional problems and mental health issues. There are over 1,000 types of psychotherapy.

Empathy - The capacity to understand and feel the suffering of others.