Last night's television:<br/>Cutting Edge: Ninety Naps a Day, Channel 4<br/>Timeshift: Between the Lines, BBC4

The big sleep that's a bit of a nightmare

Ninety Naps a Day (as far as I could make out the number was arbitrary, chosen for its alliteration) trod a fine line between the tragic and the hilarious, neatly encapsulated in a scene where Christine, the wife of a narcoleptic, talked of the appalling loneliness of 38 years of marriage. In the foreground, Kenny snored quietly: "He may as well not be here half the time". Kenny started up: "What did I miss?" Christine looked a touch weary: "Nothing. You're all right."

The main symptom is falling asleep abruptly and uncontrollably. Although most narcoleptics sleep fitfully by night, their rest is interrupted by vivid hallucinations, so that they are often tired. It is sometimes accompanied by cataplexy, a complete loss of muscular control, usually brought on by some strong emotion, such as laughter or fear. This was illustrated somewhat unhelpfully by footage of Samantha, a law student, suddenly folding in the middle of a clothes store, when it wasn't at all clear what strong emotions she was feeling, if any (outraged fashion sense?). It is a peculiarly insidious illness, partly because from the outside it hardly looks like an illness at all: after all, sleeping is something that we do for a third of our lives, often wishing it could be rather more. To the casual onlooker, the narcoleptic can look lazy, or drunk, or simply bored and rude. But those with narcolepsy find it difficult to hold down a job, study, sustain relationships, or even take a bath in case they drown - falling down in the shower isn't much of an alternative.

For the purposes of this film, Samantha, Kenny and Christine, and 14-year-old Tony travelled to the Narcolepsy Network conference in Albany, New York. None of them, it seemed, had met fellow narcoleptics before, though there are 30,000 in the UK. After a struggle to board the plane – both Samantha and Tony were unable to stay awake long enough to get through passport control – they made it, and the tenor of the film changed: instead of being a study of narcolepsy, it seemed more like a trial of American self-helpism, with a touch of the Time Team: only one day to go – can group therapy help them to come to terms with their condition before they have to catch the plane home?

For both Kenny and Samantha, the answer seemed to be no. Kenny was cross from the start about the idea of discussing his sex life with a roomful of strangers. Samantha was more receptive, but soon lost patience with hugging as a coping strategy: "We can talk about herbal remedies and we can hug and cry, but it's not going to change anything. It's still going to be as god-awful as it ever was." Tony, on the other hand, meeting other young people with narcolepsy, was thriving: aside from no longer feeling like a freak, and sharing some hallucinations (one boy appealed for reassurance that others dreamed about being eaten by giant garlic bread), he got some useful practical tips, including information about a new drug he was considering trying.

And after his initial scepticism, Kenny thawed. Christine dragged him along to a session about relationships, and talked again about her solitude. Another woman burst into tears as she told Christine how much she admired her commitment to Kenny, and the whole room gave them a round of applause for their 40-year relationship. Afterwards, Christine told Kenny that, after meeting other narcoleptics, she had finally realised how serious the condition was; evidently, some part of her suspected him of playing it up for effect. So, workshops work! Even cynical Samantha returned full of therapy speak, saying she had learned to embrace her disability: however much it was a weakness, she had to turn that weakness into strength. Then she nodded off. Hugs all round!

After this, what a pleasure to turn over to the blunt Yorkshire manner of Andrew Martin on Between the Lines, an enjoyable study of the part played by railways in fiction, from the nightmarish visions of Dombey and Son to the nostalgic view found in novels like – well, like the Jim Stringer, Steam Detective novels by Andrew Martin: an indulgent director showed him rearranging copies in a railway bookshop to make them more prominent. The programme included some smart reflections on the importance to literature of the old-fashioned compartment, which gave such impetus to the plot of thrillers like The Thirty-Nine Steps and North by North West, and on the romance of the railway canteen, as seen in Brief Encounter. At times, Martin indulged in a certain trainspotterishness. Did you know that Hitchcock got the trains all wrong in The Thirty-Nine Steps, switching between the LNER and the Great Western? Do you give a monkey's?

More serious, perhaps, was the omission of Thomas the Tank Engine, which must have been many people's introduction to the world of trains, and which also contains at least one sharp political point: when the trains were nationalised, the Fat Director became the Fat Controller. You change the structures, but the same rich bastard is still in charge. Ain't it the truth?