Detailed Instructions: Given an abstract, generate a keyword (a noun phrase) that best describes the focus or contribution of the paper. Such keywords can be directly from the given abstract or outside it.
Problem:Abstract: It is postulated that the repetitive thrust of a sensitized blood vessel, at the peak of systole, against a taut pia-arachnoid fiber may produce or accentuate vasospasm.
Solution:
Arachnoid