Which preposition to use with hyperfunction

during Occurrences 1%

In general, the major endocrines, the pituitary, the adrenals, and the thyroid should hypertrophy and hyperfunction during pregnancy.

of Occurrences 1%

In them is an increased activity of the posterior lobe in association with enlargement and hyperfunction of the anterior, overgrowth is not so marked, and the individual is lean and mentally acute.

Which preposition to use with  hyperfunction