People with elevated depression were found to be poorer at hearing all forms of emotional speech - despite a possible bias toward negative perception of information - compared with people with mild symptoms of depression, according to a new study. "Researchers tested the ability of students with either low or elevated symptoms of depression to hear and successfully understand sentences when masked with different kinds of disruptive sounds. The results of the study, presented at the 169th meeting of the Acoustical Society of America, were contrary to the authors' expectations that participants with elevated depression symptoms would be more receptive to negative emotions. They had hypothesized that the bias of people with elevated depression symptoms toward retaining sad information might lead them to pick up negative information more easily in situations where it is difficult to understand someone else's speech. ""A lot of research has suggested that these people with elevated depression symptoms have a bias towards negative perception of information in this kind of environment,"" explains Zilong Xie, a graduate student at the University of Texas at Austin. Depression is known to lead people to become more withdrawn and feel socially isolated from others. The illness can cause patients to have trouble thinking and concentrating, as well as making it difficult for them to retain information. In situations where it can be difficult to understand what a companion is saying - at a noisy dinner party, for example - depression could make the perception of speech more difficult and lead to an increased sense of isolation. There are two categories that sources of noise disruption can be placed in. Energetic masking interferes with speech perception and is caused by peripheral sources such as the clink of glasses or the movement of chairs. Informational masking is caused by linguistic or cognitive sources such as the sound of nearby conversations. Informational masking is considered to be more isolating as it often places greater stress on executive function than energetic masking."