Maharishi Patanjali's yoga is called Raja Yoga or Ashtanga Yoga. The eight limbs of yoga are (i) yama, (ii) niyama, (iii) asana, (iv) pranayama, (v) pratyahara, (vi) dharana, (vii) dhyana and (viii) samadhi include all types of yoga that happens. These eight organs also have their own sub-parts. The seventh part of yoga, "Dhyana" is beneficial in many diseases. If your memory is weak, it can be overcome by doing 10 minutes meditation and focusing on the inhaling and exhaling of the breath for 10 minutes keeping eyes closed. Do this daily, but for at least 30 days.