Personally, I tend to learn better in the early morning. There has been research done looking at core body temperature and relating it to memory retention rates, often finding that cooler temperatures led to better memory. Although, at the beginning of this year I saw an article that countered a few other studies and suggested that it was in alignment with normal sleep wake cycle (that is, higher temperatures = better memory). http://www3.interscience.wiley.com/journal/121643259/abstract?CRETRY=1&SRETRY=0 The later actually seems to make more sense, considering the importance of alertness in memory (and alertness is higher at peak of the sleep-wake cycle when temperature is highest). [After checking again apparently this journal article is from 1991 - surprised I hadn't seen it for so long...though in my defense, I'm not sure I could read when it came out!]

My "mornings" would have been around the peak of my cycle, as I woke up at 4-5am for meditation and other shenanigans, and got/get into 'life' at 9-10am.

Some research (again with the sleep-wake cycle) has shown memory (in students - though such studies have probably been done on others I can't recall reading them) retention rates peak at different times for different individuals - late morning for 'larks' like myself, and evening for 'night owls'. Supposedly, teenagers sleep wake cycle is shifted far later than 'normal' and as one gets older, it tends to shift earlier.

There's research suggesting before sleeping is most effective - which would suggest late at night too. With the theory that sleeping prevents new information interfering in the short term memory being transferred to long term memory. Personally, I always had issues falling asleep straight after learning new things...but I suppose I tend to be obsessive and excited over it - a bit of an information junkie, alas.

So...for me earlier works better to get new information into memory(after I get going a bit). Most research I've read suggests individual differences, with a tendency towards earlier - with a primary exception for teens [although one that never applied to me]. After something is 'in my head' though - I always find I learn the most while sleeping. :)

My best time is late at night after everyone else has gone to bed, and everything is absolutely quiet.

When I went back to school and got my degrees, I spent many a night writing papers until 2 in the morning. I found this generally to be my most productive time.

Apparently many computer programmers are like that. It is one of the personality quirks that comes with the profession.

I find that I am generally more productive in the mornings and that includes learning. I think it is to do with the fact that after a good night's rest, I am very refreshed and energetic which increases my keenness and focus.

I think every person has their own rhythm, and instinctively knows at which time of the day or night, they are at their sharpest, and dullest.