Reduce space after chapter heading using memoir

Question

Is there a way to reduce the vertical spacing between the chapter heading and the text separatedly from mainmatter and frontmatter?

Here is my custuom MWE:

\documentclass[14pt,twoside,a5paper,extrafontsizes]{memoir} %Classe estilo memoir
\usepackage[brazilian]{babel} %Traduz doc para português do Brasil
\usepackage[utf8]{inputenc} %Reconhece acentuação
\usepackage{indentfirst} %Define identação em todo primeiro parágrafo
\usepackage{garamondx} %Define a nova fonte garamond
\usepackage{lipsum}
\usepackage{tabularx}

\chapterstyle{thatcher}

\begin{document} %=========================================================================
    \renewcommand{\printchaptername}{\centering{\chapnumfont\HUGE\thechapter}}
    \renewcommand{\afterchapternum}{\par\bigbreak}

    \frontmatter

    \chapter{Introduction}
        \lipsum[2]

    \mainmatter

    \chapter{Development}
        \lipsum[2]


\end{document}

Answer 1

The space between the chapter heading and the following text is determined mainly by \afterchapskip. Its default definition is 40pt. For more details see pp. 86-90 (chap. 6.5) of the memoir documentation. You can reduce the space by redefining that length.

\documentclass[14pt,twoside,a5paper,extrafontsizes]{memoir}
\usepackage[brazilian]{babel}
\usepackage[utf8]{inputenc}
\usepackage{indentfirst}
\usepackage{lipsum}

\chapterstyle{thatcher}
\renewcommand{\printchaptername}{\centering{\chapnumfont\HUGE\thechapter}}
\renewcommand{\afterchapternum}{\par\bigskip}
\setlength{\afterchapskip}{\baselineskip}

\begin{document}
\frontmatter
\chapter{Introduction}
\lipsum[2]

\mainmatter
\chapter{Development}
\lipsum[2]
\end{document}

Note that I used \bigskip instead of \bigbreak, since according to Lengths and when to use them \bigbreak would encourage page breaking, which I don't think is appropriate at that point.