Caution: the following is a little technical. Yoga is meant to be experienced, not explained. Jnana (intellectual understanding) may be one of the ways pointing towards enlightenment. But it is nothing without accompanying practice.
I was recently asked if Kundalini Yoga can remove samskaras. Samskaras are the mental formations we might call "personality traits" in the West. Some traits are undesirable, particularly habits of thought. Can Kundalini Yoga help to shed this kind of karma?
What I'm in the process of learning is that when exploring Kundalini Yoga (I'll shorten it to KY) by way of Jnana, there are two perspectives which need to be discussed: one point-of-view is that of Sikh Dharma, the other is more holistic.
KY's natural history runs through the Raja tradition of India, but today it is primarily interpreted by the Sikhs (in particular, Yogi Bhajan, who broke with tradition by teaching KY in America starting in the '60's).
The Sikhs have always had a kind of democratic impulse and they believe Kundalini raising technologies is everyone's birthright, not just the Raj. However, that means that a lot of KY theory has been sifted through the filter of Sikhism. In the process, its classical roots have been somewhat appropriated or transfigured on behalf of religious devotion (bakhti).
The second perspective that a lot of teachers embrace is more expansive than orthodox Sikhism. I can say with some confidence that KY practitioners keep coming back to the studio because the primary benefit is: awareness. I think if we see KY through the lens of "awareness training" then a lot of things start to make sense.
The huge emphasis in KY on meditation, breath, and rigorous movement catapult the mind (very quickly) into unordinary states. In order to do this, there are some pretty significant departures from classical yoga built into the current practice. This is especially true of the asanas. For example, a single KY asana may include and collapse up to three classical poses--it telescopes them by emphasizing movement and flow in (tri)angles. By classical standards, asana accuracy is sometimes sacrificed for efficacy.
This is especially true when it comes to KY's emphasis on the endocrine and nervous systems. In particular, KY hyper-stimulates the parasympathetic system while sending a lot of oxygen into the midbrain. Some believe that this triggers the Pineal Gland which may release elevated amounts of D.M.T. (sometimes called "the spirit molecule").
Whatever the internal mechanism, I can tell you that my mindfulness consistently goes way up during practice. Personally, I find that in contrast to other forms of yoga, the mind on KY looks at itself in a very reflective way. I have a friend who calls KY: Postmodern Yoga... because the mind becomes so aware of its own mechanisms.
So... to approach an answer to the question of samskara, I can discuss the Sikh explanation and also have a go at a more intuitive approach.
The Sikhs believe that there are specific times of the day when the self passes through a kind of twilight zone. During these periods, samskaras are most vulnerable to change. These times are called "Amrit Vela" (ambrosial hours)--they are between 4AM and 7AM and 4PM and 7PM. The Sikhs believe that it is then that our minds are in tune with "Ava Gavan" (a transient stage trending towards Nirvana) and if we do yoga with mantra recitation during this time, then "Guru" (the inner teacher, not an external teacher) will recognize the natural balance of the tattvas (aspects of reality) and correct the imbalances caused by samskaras. In this view, karma actually shapes the five tattvas: fire (anger), air (attachment), earth (greed), and ether (pride). Yoga, then, acts to balance karma/tattva by activating "Guru," the primal spiritual intelligence of every being.
Personally, I find this explanation dissatisfying because it requires faith in a cosmology. Though, it is worth saying that many, many cultures believe in an almost identical narrative. The 4AM to 7AM window is especially cherished in Tai Chi and Sufi practices.
But I'm much more enthusiastic about applying Buddhist philosophy here.
Virtually every Eastern discipline, stemming from a Vedic tradition, agrees that "volitional arisings" or "form-created-by-mind" is at the root of suffering and samskara. But there is significant disagreement about what causes the arising of these conditions. In Buddhism there is a total evacuation of metaphysics in favor of a psychological approach.
According to this view, in the beginning of everything there is avija or "ignorance" (not God, or the Word).
Here is a list (more of a feedback loop, really) of the 12 Nidanas. The Nidanas describe the contingent process of how we accumulate dukkha (suffering, stuck mind).
Ignorance
↓
Formations
↓
Consciousness
↓
Mind & Body
↓
Six Sense Bases
↓
Contact
↓
Feeling
↓
Craving
↓
Clinging
↓
Becoming
↓
Birth
↓
Old Age & Death
The Buddha believed that these contingent conditions arose because of ignorance of the relationship between form, consciousness, feeling, perception, and, finally, formation. This is how samskaras arise.
Kudalini Yoga has the ability to drive a wedge into the ignorance cycle.
The unique emphasis in KY on pranotthana or intensified and repeated movement of the six senses forces the mind to discern the difference between bodily pain (unavoidable) and mental suffering (optional). We realize that physical/mental formations do not need to cause changes in consciousness. The difference between "contact" and "feeling" is highlighted by the fact that we practice KY with our eyes closed. Lots of mantra and meditation are also utilized to enunciate this kind of awareness.
We also put emphasis on the body locks (bhandas) in KY. In fact, mulbhand (root lock), is applied pretty much throughout. Pranayam (breath) dynamics aside, the bhandas have the effect of putting clinging into your conscious control. Very quickly, then, one learns to skillfully uncling through this process. Impermanence becomes very literal.
Finally, breath control is the crown jewel of the practice. We practice something called "Breath of Fire" endlessly. This preps us for stopping the breath. This is said to cause mahanidra (the temporary death of the great nerve). Basically, this is as close to death as one can get. No breath. This is the most important stage in undoing samskaras. If we can master our striving and our clinging to our lives then wisdom may follow.