Different states of consciousness are connected with different levels of focus and even increased creativity. They may be induced through meditation, yoga practice or through pharmacological substances. They may also occur unintentionally, through accidents, trauma or medical conditions such as epilepsy.
There are four main types of brain waves which are associated with different states of consciousness: alpha (deep relaxation or meditation), beta (alert awareness), theta (light sleep) and delta (deep sleep).
In yoga, practices such as yoga nidra aim to shift the state of consciousness to a state which is deeply relaxed and meditative, yet awake. As such, the yogi will have a heightened awareness of their inner world.