Change heading style in latex environment

Change heading style in latex environment

I am using the acronym environment to list some acronyms at the beginning
of a thesis I am writing. However the default heading style that acronym
places doesn't match the rest of my document. I don't know lots about
defining a class myself but I did this for my contributions and abstract
pages.
\newenvironment{contributions}
{\pagestyle{empty}
\begin{alwayssingle}
\begin{center}
\vspace*{1.5cm}
{\Large \bfseries Contributions}
\end{center}
\vspace{0.5cm}
\begin{quote}}
{\end{quote}\end{alwayssingle}}
however the acronym environment does a left align heading under a line
that spans the width of the page. Is there anyway to override this style
to match the rest of my pages?
Cheers!