a person who has average/high levels of intelligence but is unbelieveably slow at undertaking menial tasks, such as washing up, pouring a glass of water or trying to tie their shoe laces. following in on from this, people who they then come into contact with, end up becoming slow at tasks they are involved with, even if they are usually efficient.
Ben: hey buddy, howcome you're taking so long? we're going to miss our flight?
Tim: sorry, ive just been on the phone to matt, i don't know whats gotten over me
Ben: the barker effect strikes again