citta vritti nirodaH
Sensory inflow is 1st layer. Perception due to function of chemicals/ nerve impulse/ vital force is 2nd layer. Psyche/ Mind/ manas as sense organ/ perception organ/ executioner of will is 3rd layer. Intellect/ buddhi is 4th layer/ jiva. Bliss/ ananda is 5th layer - Self/ purusha.
1- anna 2- prana 3- manas These three material in nature/ prakriti 4- vijnana is covering of I-consciousness 5- ananda is covering of Shiva-consciousness/ purusha
Junction of 3rd & 4th along with another manifestation of prakriti- ego/ ahankara, is Conscience/ antahkaran. That voice in head is ego.
Light of consciousness makes reflection on antahkaran is citta. Cosmic correlate of buddhi is mahat. Cosmic correlate of citta is cit.
Mind/ manas is material in nature. Manas takes shape of whole body but in awake state, cerebrum is its seat. In dream, cerebellum is its seat. In sleep, heart is its seat.
Mind along with sense organs & sense perception is only an instrument, originated from prakriti.
citta is union of manifestation of purusha with prakriti. It has 3 functions - 1 Cognition (buddhi) 2 Conation (will of I-consciousness via ego - ahankara) 3 Motion (natural state of manas) Every experience leaves behind impressions. Citta is storehouse of impressions/ sanskaras.
Motion in citta is vritti. These movements in citta are 5:
1 Correct knowledge- right interpretation- pramana 2 Distorted knowledge- Illusion- viparyaya 3 Fanciful/ imaginary knowledge- Delusion- vikalpa 4 Memory- Not letting vritti to subside- smriti 5 Sleep- nindra
When manas is ONLY sense organ active, it becomes Ekendriya. When there's only ONE single vritti being formed again & again each moment then it's dhAranA. When ego weakens & motion stills (dhyAn) then cognition merges with watchful witnessing- Wisdom (samAdhi)
योगः चित्तवृत्ति निरोधः yogaH citta vritti nirodhaH "Yoga is the cessation of movements in the citta" This is called Yoga!