1.6 pramana viparyaya vikalpa nidra smrtayah
pramana: valid / correct knowledge
viparyaya: inverted, perverse
vikalpa: doubt, indecision, imagination or day-dreaming
nidra: sleep
smrtayah: memory
They are caused by correct knowledge, illusion, delusion, sleep and memory.
The five-fold fluctuations of consciousness.