Sommers Mitchell S, Phelps Damian
Department of Psychology, Washington University in St. Louis, St. Louis, Missouri, USA.
Ear Hear. 2016 Jul-Aug;37 Suppl 1(Suppl 1):62S-8S. doi: 10.1097/AUD.0000000000000322.
One goal of the present study was to establish whether providing younger and older adults with visual speech information (both seeing and hearing a talker compared with listening alone) would reduce listening effort for understanding speech in noise. In addition, we used an individual differences approach to assess whether changes in listening effort were related to changes in visual enhancement-the improvement in speech understanding in going from an auditory-only (A-only) to an auditory-visual condition (AV) condition. To compare word recognition in A-only and AV modalities, younger and older adults identified words in both A-only and AV conditions in the presence of six-talker babble. Listening effort was assessed using a modified version of a serial recall task. Participants heard (A-only) or saw and heard (AV) a talker producing individual words without background noise. List presentation was stopped randomly and participants were then asked to repeat the last three words that were presented. Listening effort was assessed using recall performance in the two- and three-back positions. Younger, but not older, adults exhibited reduced listening effort as indexed by greater recall in the two- and three-back positions for the AV compared with the A-only presentations. For younger, but not older adults, changes in performance from the A-only to the AV condition were moderately correlated with visual enhancement. Results are discussed within a limited-resource model of both A-only and AV speech perception.
本研究的一个目标是确定为年轻人和老年人提供视觉语音信息（与仅听相比，同时看到和听到说话者）是否会减少在噪声中理解语音的听力努力。此外，我们采用个体差异方法来评估听力努力的变化是否与视觉增强的变化相关——即从仅听觉（仅A）条件到听觉-视觉（AV）条件下语音理解的改善。为了比较仅A和AV模式下的单词识别，年轻人和老年人在有六个说话者的嘈杂声的情况下，在仅A和AV条件下识别单词。使用串行回忆任务的修改版本来评估听力努力。参与者听到（仅A）或看到并听到（AV）一个说话者说出单个单词，没有背景噪音。列表呈现随机停止，然后要求参与者重复最后呈现的三个单词。使用二-back和三-back位置的回忆表现来评估听力努力。与仅A呈现相比，年轻人（而非老年人）在AV条件下二-back和三-back位置的回忆率更高，表明听力努力降低。对于年轻人（而非老年人），从仅A条件到AV条件的表现变化与视觉增强呈中度相关。在仅A和AV语音感知的有限资源模型中讨论了结果。
