"I remember waking up one morning and realising I was in hospital and looking quickly to see what my body looked like and finding that I had all my attachments," he said.
A nurse explained he had been in hospital 10 days and although he could not remember, Mr Sullivan had been in and out of consciousness, conversing and interacting with visitors including his parents during that time.
"I don't remember 10 days of my life," he said. "I don't remember anything about that, and still don't."
However, memory from the month before the accident, which had also disappeared, slowly returned over the months following the crash.
These days, it's those months after the accident that remain hazy and Mr Sullivan said he sympathised with Mr Price.
"It's a horrible thought. Your life is a series of experiences and if they're taken away ... if you lose your memories what have you got?
"My case wasn't anywhere near as bad as Robbie's, but my father said it changed my personality. It made me less aggressive than I was before."
Mr Sullivan suffered bad headaches for about six months after the crash and was told he could never cycle again. However, he still cycles and mountain bikes, and today he runs an online business selling mountain biking apparel.
Meanwhile, Mr Price is under strict orders from doctors to rest for the next fortnight. The 43-year-old scientist crashed into a traffic sign placed in a cycle path on his way to work and woke up thinking he was 33 and still living in Australia.
Mr Price knew his wife but thought his two teenage sons were still aged 5 and 3.
He couldn't remember anything that had happened during the past decade including major world events such as the Christchurch earthquakes.
This week, he said a "few minutes" of memory had returned but he had begun suffering headaches.
