To take a slightly different example, psychiatric medication tend to suppress or modify parts of the brain's activity to control the symptoms of mental diseases. You can read about the mechanism of action of antipsychotics for example. More often than not, when the drugs are stopped, the symptoms of the disease returns. I have a friend who is on psychiatric medication, and to me, it seems that a part of his personality is missing, perhaps switched off, along with his mental disease, which is still there but simply suppressed. I felt sorry to notice that a part of him is missing.
On the other hand, recent research reveals that mindfulness and Buddhist meditation can help patients go off long term medication according to this article:
"We've seen this in the clinical domain for many years. People, in
concert with their physicians... actually going off their medications
for pain, for anxiety, for depression, as they begin to learn the
self-regulatory elements of mindfulness," said Kabat-Zinn. "They
discover that the things that used to be symptomatically problematic
for them are no longer arising at the same level."
So, if you ask me, I think that the 2,500 year old techniques taught by the Buddha, referenced from very old sources like the Anapanasati Sutta are hardly being made obsolete by modern neuroscience and psychiatry.
Casts and crutches only help a man while his fractures heal naturally and then would in due time be discarded.
Similarly, neurosurgical and pharmacological interventions should be seen as temporary aids while man heals himself by natural means. In this case, meditation may help man discover how to control and self-regulate his mind, and become detached from repetitive thoughts that ail him. Of course, in very serious cases, meditation won't be possible.
On the other hand, if modifying our neural networks is enough to reach nirvana, then this implies that all that we are is contained in the physical body and there is nothing beyond. This means that when the physical body perishes, the self would be completely destroyed. Rebirth would not be possible. This seems to be leaning towards annihilationism, which has been refuted by the Buddha as a wrong view.