本文調查分析台灣中部華語的聲調特徵，為社會語言學的語音變異研究。結果顯示，中部華語的高頻點音頻下降至次高頻點，尤以第一聲最明顯。本研究推測，中部華語的高頻點音高下降，可能是台華語接觸初期，由台語移轉(transfer)至華語的特徵之一。華語的高平調型降為中平調型，不但差異不大，也不致普遍影響辨義，可能也是中部華語擴散的原因。本研究還從台灣華語的形成過程，探討「台中腔」一詞出現的背景。華語在台灣經過集體L2習得、等化、定著等過程後，大約在一九九○年代形成台灣華語。過去未被注意的中部華語聲調特徵，也因台灣華語的穩定而浮現，並出現「台中腔」一詞。不過，「台中腔」一詞的涵義仍在變動，似乎和「台灣國語」一詞部分重疊。

This is a preliminary study of Central Taiwan Mandarin tonal variations, better known as Taichung Qiang, literally Taichung accent, an innovative but neither well-agreed nor well-defined term. Results indicated that the pitch of the high register points of CTM were lowered to semi-high. This lowering further pushed one semi-high register point to mid-register. It was suggested that the pitch lowering of CTM T1 was originally an L1 transfer from certain central Taiwanese dialects. This transfer occurred in as early as not long after WW II but had not been noticed until the 1990s, roughly overlapping with the focusing of Taiwan Mandarin. The late notice of this tonal feature may be partly attributed to the fact that high level tone and mid level tone are not in tonemic relation, and thus not as salient as segment transfers. This study also noticed that the expansion of the reference of CTM. It originally referred only to “a Taiwan Mandarin dialect spoken in Taichung”, but now the reference is expanding to partly overlapping with Taiwanese Mandarin, a term roughly equals non-standard Mandarin in Taiwan.