Chit vrittis are modifications of consciousness. It is derived from the etymology chit+vriti, where chit means consciousness and vritti means modification, waves or whirlpools. Therefore any kind of activity or flux in the field of ones consciousness is called a vritti. The term is first defined by [wiki]Patanjali[/wiki] in the [wiki]Yoga sutras[/wiki] in the famous second sutra giving a definition of Yoga: [I]Yogas chit vritti nirodha[/I]. It can be understood as a scientific way of classifying all physical, mental and emotional state changes such as the rising and falling of thoughts, emotions, changes in awareness and even sensory activity. It is commonly used to refer to the activity of thoughts in the mind. If one says, “My vritti activity is high” they mean their mind has racing thoughts. The aim of Yoga is to bring the vritti activity down and ultimately to still the activity altogether.
Patanjali states that vritis can either be perceptible (conscious) or non perceptible (unconscious) or pleasant and unpleasant. He identifies 5 major types of vrittis: correct knowledge, fallacious knowledge, fantasy, memory and sleep or awareness states. In later traditions like Tantra, as many as 50 different forms of vrittis are identified such as anger vrittis, depression vrittis, joy vrittis, inspiration vrittis etc. Thus, vrittis are not necessarily all negative, but nonetheless all vrittis are modifications of the original pure consciousness state (chit), hence they are all undesirable to the yogi.