According to the Vedic philosophy, we come across the concept of Samskaras, which can literally be translated as impressions. These are the subtle mental impressions left on our citta (consciousness) in the form of thoughts, intentions and actions that an individual has ever experienced. It is said that one’s behavioural patterns are determined by the sum total of all these impressions gathered over time. They drive our impulses and desires.
https://www.inc.com/angelina-zimmerman/13-fascinating-facts-about-your-brain.html
Likened to groves in the mind, these are psychological and emotional imprints which form one’s nature and character traits. Samskaras also form the bases of Karma giving rise to rebirth. They make up the sum total of all our conditioning. When one repeats a samskara, it is reinforced thereby deepening the groove. By adopting mindfulness and self-awareness, one is able to navigate these behavioural patterns and transform the negative ones to positive ones. For example it is only due to past samskaras that one person may gravitate towards unhealthy habits such as smoking or drinking, while the other may take up a spiritual path of growth and enlightenment.
Samskaras are born out of Vrittis (or thought waves) which cross the mind. These vrittis settle down in the subconscious or unconscious states. They can be likened to memory stores which hold all past experiences. These stored memories are recalled when one is confronted with a particular situation. These impressions gathered over many lifetimes continue to build in the present life. Samskaras are closely related to the concept of Karma wherein the accumulated actions from previous lifetimes pass on to the next birth. Samskaras form the root of both the pleasurable and painful interpretations of experiences. When samskaras govern our thoughts and actions, overpowering our discerning abilities, they are called Vasanas.
Initially breaking these past impressions can seem daunting and require intense work and regular practice through Tapasya (perseverance) born out of a strong Sankalpa (intention). Eventually one is able to transcend those negative samskaras. Through the Yogic practice of meditation (dharana and dhyana), one can overcome the self limiting habits and gain a broader understanding of the self. One then acts from a position of awareness and alters the mental patterns consciously. The citta (or consciousness) of such a person becomes like an ocean which is calm and steady. Ripples and waves may come and go, but the ocean remains as it is.