Almost one in 10 youngsters would immediately take to social media to tell their friends and followers if they saw a stranger in a risky situation, a poll suggests.
Nine percent of 18 to 24-year-olds would write a post on Facebook or Twitter or share a photo, the poll by Anthony Nolan found.
And 15% of 18 to 24-year-olds have pretended to be on the phone or texting to avoid helping a stranger who was in danger, the blood cancer charity said.
Meanwhile 6% of people aged 25 to 34 would post about such event on social media. And 7% of people in this age group would take a photo on their mobile phones.
Overall, 3% of people said they would take to the internet if they saw a stranger in trouble, with older people less likely to post about such an incident online.
The poll comes after an epileptic woman spoke out about two strangers who refused to help her during a fit but were instead laughing and filming her on their mobile phones.
Maggie O'Connor was walking her dog Dillion in Colchester, Essex, when she had a fit.
She awoke to find two men standing over her and filming her. She wrote about the incident, which happened last week, on Facebook to try and track down the men, who were described as in their 20s and wearing skinny jeans.
"Today I had a seizure walking the dog at the priory," she wrote.
"It was a bad one. I'm not going to lie I wet myself and bit my tongue, so had blood down my front. This I'm all used to. It's been a long time since I've felt upset by having a seizure in public. But today when I came round Dillion was standing over me which made me look up to see two lads laughing and filming me on their phones.
"Even though I had woken up they only stopped filming because the dog started growling. One even took the time to do a close up of my face... these lads should be shamed for their behaviour."
Anthony Nolan, which polled 2,300 British adults including almost 300 people aged 18 to 24 and another 300 aged 25 to 34, also found that 70% of people claim they would be willing to donate their stem cells to a stranger - yet only 0.8% of the British population are on the Anthony Nolan register, a spokeswoman said.
The charity, which is celebrating its 40th year, matches people who are willing to donate their blood stem cells or bone marrow to those desperately in need of a transplant.
Last year it matched around 1,200 donors - helping or saving the lives of around three people each day.
Anthony Nolan chief executive Henny Braund said: "We can all be guilty of seeing a stranger in need and assuming someone else will help.
"But every day, three amazing donors give someone the chance of life by donating their stem cells, without knowing anything about the person they are helping. That is quite remarkable."
:: Anyone aged 16 to 30 in good health can sign up to the register. To find out more visit: www.anthonynolan.org.