on one's mind
nag
leap to mind
haunting
persistent
spring to mind
cross someone's mind
train of thoughts
hang
stream of consciousness
stir
come to mind
circuit
recurring
perseveration
intracognition
live rent-free in someone's head
think about
daydream
hammer home
brainful
tachyphrenia
brain cloud
bemused
self-involved
mindful
in agreement
broody
in mind
lost
preoccupied
intrapersonally
metacogitate
in one's opinion
credulity
recept
puzzle
like-mindedness
rumination
internal monologue
self-debate
back up
get ahead of oneself
not leave one's thoughts
thought pattern
academicism
multiplist
absorbed
crimethink
ponderomotively