On Second Thought...

naisip = thought of

napaisip = brought one's mental gears into motion

naglaro sa isip = considered

masusing pag-iisip = carefully thought

malalim ang isip= in deep thought

malawak ang isip = broad-minded

malikot ang isip = imaginative

malikhain = creative

malinaw ang isip = clear-minded

malabo ang isip =  fuddle-minded

magulo ang isip = mentally disturbed

matalas ang isip = analytical-minded, sharp-minded

mapurol ang isip = dim-witted

mababaw ang isip = shallow-minded

magaslaw ang isip = green-/horny-minded

marumi ang isip = dirty-minded, also evil

makitid ang isip = narrow-minded

sarado ang isip = closed-minded

nagdilim ang isip = lost one's senses

isip-matanda = mature

bungang-isip = idea

nagbagong-isip = changed one's mind

naguluhan = got muddled

nalito = got distracted

natuliro = got frazzled 

sira ang ulo = crazy

may toyo/may baltik sa utak = perverted 

naalaala = brought to mind with nostalgia

natandaan = remembered

naisaulo = memorized

nagunita = reminisced

nanumbalik = recalled

nanariwa = remembered clearly and vividly 

sumagi sa isip = crossed one's mind

nabasa ang isip = read another's mind

nalirip = conceived

nahinuha = inferred

nag-akala = mistakenly thought

nagkamali =  mistook

naghinala = suspected

narating = concluded

natunton = ended up with

nagpasiya = decided

naghusga = judged

kinilatis = assessed the value of something

nagdalawang-isip = on the verge of changing one's mind

nagpantasya = fantasized

isip-bata = mentally challenged, also innocent

utak-biya = idiotic

nakalimutan = forgot

malimutin = forgetful

nalingatan = overlooked

ulyanin = senile

matalino = intelligent

madunong = wise