Dr Kerzin (who reportedly made the claim) might have been misunderstood by the reporter and/or the editor of the article.
It might be truer to say that he is dead and meditating (for some suitably vague definition of "him", given that the self is difficult to define and that Tibetan Buddhists believe in a continuing existence after death and rebirth).
The following are the first three definitions of "tukdam" which I found using Google.
Tukdam
Tukdam (Wyl. thugs dam) is an honorific term for meditative practice and experience that is frequently used to refer to the period following the death of a great master, during which time they are absorbed in luminosity.
Parinirvana --
Kyabje Tenga Rinpoche's Tukdam has ended
On 3 April, at 3:15 p.m., Kyabje Tenga Rinpoche chose to end the state of Tukdam, which is the deep meditative composure that some realized masters enter into after the demise of their physical bodies, after three and a half days.
Interview with Khenchen Thrangu Rinpoche after the passing of Tulku Urgyen Rinpoche
Generally speaking, tukdam comes about when someone has rested evenly in luminous wakefulness during his life, usually called samadhi, and occurs to the same degree as his experience. When he then passes away, there is what we call 'the mingling of the mother and child luminosities,' which means that the ground luminosity and the luminosity of that person's practice mingle indivisibly.
At that moment, the experience of luminous wakefulness is very strong and one simply remains in its composure naturally, meaning that high lamas or someone with deep experience and realization will naturally dissolve into or expand into this state of samadhi. When the ground luminosity dawns by itself, they recognize it, and then remain in equanimity - that is what is called 'remaining in tukdam.'
No doubt an ordinary person also experiences the ground luminosity, but because of not having trained in it during their life, they don't recognize this ground luminosity, and failing to recognize, they are therefore unable to remain in tukdam. On the other hand, great masters naturally mingle the mother and child luminosities, - in the very moment the ground luminosity unfolds within their direct experience, they acknowledge this basic state and remain in samadhi this is called 'remaining in tukdam.'
It is due to the strength of the samadhi that the body heat doesn't disappear completely, that the skin color doesn't fade, and that the body is able to remain in an upright sitting posture. Due to such visible signs, we are able to conclude that the person is in tukdam.