7 years; SD = 3 3) and older adults (n = 20, 10 women, M = 68 1 y

7 years; SD = 3.3) and older adults (n = 20, 10 women, M = 68.1 years; SD = 3.4). All participants were native German or Swiss German

speakers and right handed according to the Annette Test for handedness (Annett 1970). All participants gave their informed written consent. The local ethical committee selleck chemicals llc permitted the study. Stimulus material Inhibitors,research,lifescience,medical Stimulus material consisted of 120 German words and 120 pseudowords. All words and pseudowords were disyllabic and corrected to a length of 800 msec using the Praat Software (Boersma 2002). Pseudowords were designed to respect rules of German phonotactics. The stimuli were spoken by a professional female speaker and recorded at a rate of 44.1 kHz. Additionally, two white noise stimuli of 500 and 1000 msec duration were generated. All stimuli were matched in intensity (amplitude Inhibitors,research,lifescience,medical normalization

with the Praat Software). Stimulus material was presented using Presentation software, Version 14.9 (http//www.neurobs.com). Procedure Before the EEG tasks commenced, participants were asked to complete behavioral tests assessing their speed of information processing (Kurztest für die Basisgrösse allgemeiner Intelligenz [KAI]; Lehr et al. 1991) and mental lexicon (Mehrfachwahl-Wortschatz-Intelligenztest [MWT-B]; Lehr 1977). Furthermore, older participants’ hearing performance was controlled for (MAICO ST20; MAICO Diagnostics Inhibitors,research,lifescience,medical GmbH, Dortmund, Germany). This has been done to ensure the participant’s appropriate hearing threshold. During the EEG experiment, participants were seated in a comfortable position about at a 1 m distance Inhibitors,research,lifescience,medical from a monitor in an electromagnetic and sound shielded booth. Stimulus material was presented via in-ear headphones (Sennheiser CX271, Sennheiser (Schweiz) AG, Unterengstringen, Switzerland) for two independent tasks, a “speech task” and a “nonspeech task.” To control for possible learning effects, 50% of the participants of each age group started

with the speech Inhibitors,research,lifescience,medical task, the other half of the participants started with the nonspeech task, respectively. No explicit feedback was given during the experiment. In the “speech task,” participants heard randomly presented words and pseudowords. Participants were instructed to decide if the previous heard stimulus was either a real word or a pseudoword. The “nonspeech TCL task” consisted of an additionally presented white noise stimulus as deviants between words and pseudowords. In this “nonspeech task,” the participants’ task was to distinguish between the duration (either short or long) of the previously heard white noise stimulus. Participants were instructed to listen carefully to all of the presented stimuli. Additionally, participants were required to respond via button press at random time intervals indicated by a question mark on the screen (Fig. 1).

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