That 2.5 year thing sounds like the 5 second memory thing for goldfish. That is to say, it isn't true. The human brain is the most complex structure we know ab

That 2.5 year thing sounds like the 5 second memory thing for goldfish. That is to say, it isn't true. The human brain is the most complex structure we know about, there is no way we can know for certain when the first memories form. There are many references to unborn babys knowing certain types of music their mother listened to while pregnant, positive associations with food that their mother ate while pregnant, crying with a particular accent etc.