'vasana' or Impressions and Rebirth

   The phenomenal objective world is the product of 'desire' followed by resolve and action.Behind all these lie the imagination and images appearing on the mind screen. Even before the ideas are created lies the mysterious 'vasana', previous impressions! These impressions are the carry-over residues, may be, of several previous lives! It is believed that all the desires are not fulfilled at one go in one life or two lives since the jiva departs along with the impressions, memories, and things experienced even before they are fulfilled! The mind, Intellect, and ego withdraw from the dying person and depart along with the prana. These come back with the prana when the jiva takes another body, not necessarily in the same form of the previous birth! Thus, a human being dying may take birth as a cat or a dog and will have to wait to experience the unfulfilled desires till another human form is taken! This chain of births and deaths goes on and on until the jiva realizes its folly of its journey in this death knell, planet earth and takes steps to revert to its pure state! Whether one believes in rebirth or not is a different matter. Bhagavan Shree Krishna has emphatically stated that this eternal bondage that has accrued to jiva due to its ignorance, avidya, has to be terminated with the help of realization of its true nature. This realization of the true nature of the Self is Atmajnyan. Atmajnyan cannot be had without the help of a guru and practice of yoga. The jiva is finally relieved from this eternal bondage when it burns all its karma klesha and vasana. Thus the jiva attains to its pristine state.
  The Bhagavad-Gita (Ch. XIV Verses 14-19) explicitly states that all that we see is nothing but the 'quality of nature' (guneshu gunavartante). The jiva display the quality it has imbibed from nature. The persons who died with the predominant guna of sattva, rajas, or tamas at the time of departing the body will take birth again in that respective quality and displays that quality (guna) as a sagely person, or demoniac person, or even an insect! That's all. There is no secret here since Bhagavan Shree Krishna has revealed all these secrets in jnyana-vijnyan yoga (Ch. VII). As regards, the means of transcending this trap, He, the Lord, advises Arjuna to take to transcend all tattva and guna, and take to yoga.  He says, sarva dharma parityjya. .. .. | nistraigunyobhavaarjuna | tasmad yogirbhava Arjuna |

   It is often observed how those who died in accidents have taken another body and continue with the same skills and appear as child prodigies! These are matters of spiritual nature than material and needs to be realized with the help of yoga than learnt from scientific research.