This article was downloaded by: [Barbara Tillmann] On: 08 April 2013, At: 13:10 Publisher: Routledge Informa Ltd Registered in England and Wales Registered Number: 1072954 Registered office: Mortimer House, 37-41 Mortimer Street, London W1T 3JH, UK Memory Publication details, including instructions for authors and subscription information: http://www.tandfonline.com/loi/pmem20 Working memory for pitch, timbre, and words Katrin Schulze a b & Barbara Tillmann a a Lyon Neuroscience Research Center, Auditory Cognition and Psychoacoustics Team, CNRS UMR5292, INSERM U1028, Université de Lyon, Lyon, France b Developmental Cognitive Neuroscience Unit, UCL Institute of Child Health, London, UK Version of record first published: 01 Nov 2012. To cite this article: Katrin Schulze & Barbara Tillmann (2013): Working memory for pitch, timbre, and words, Memory, 21:3, 377-395 To link to this article: http://dx.doi.org/10.1080/09658211.2012.731070 PLEASE SCROLL DOWN FOR ARTICLE Full terms and conditions of use: http://www.tandfonline.com/page/terms-and-conditions This article may be used for research, teaching, and private study purposes. Any substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any form to anyone is expressly forbidden. The publisher does not give any warranty express or implied or make any representation that the contents will be complete or accurate or up to date. The accuracy of any instructions, formulae, and drug doses should be independently verified with primary sources. The publisher shall not be liable for any loss, actions, claims, proceedings, demand, or costs or damages whatsoever or howsoever caused arising directly or indirectly in connection with or arising out of the use of this material. Memory, 2013 Vol. 21, No. 3, 377Á395, http://dx.doi.org/10.1080/09658211.2012.731070 Working memory for pitch, timbre, and words Katrin Schulze1,2 and Barbara Tillmann1 1Lyon Neuroscience Research Center, Auditory Cognition and Psychoacoustics Team, CNRS UMR5292, INSERM U1028, Universite´ de Lyon, Lyon, France 2Developmental Cognitive Neuroscience Unit, UCL Institute of Child Health, London, UK Aiming to further our understanding of fundamental mechanisms of auditory working memory (WM), the present study compared performance for three auditory materials (words, tones, timbres). In a forward recognition task (Experiment 1) participants indicated whether the order of the items in the second sequence was the same as in the first sequence. In a backward recognition task (Experiment 2) participants indicated whether the items of the second sequence were played in the correct backward order. In Experiment 3 participants performed an articulatory suppression task during the retention delay of the backward task. To investigate potential length effects the number of items per sequence was manipulated. Overall findings underline the benefit of a cross-material experimental approach and suggest that human auditory WM is not a unitary system. Whereas WM processes for timbres differed from those for tones and words, similarities and differences were observed for words and tones: Both types of stimuli appear to rely on rehearsal mechanisms, but might differ in the involved sensorimotor codes. Keywords: Working memory; Auditory processing; Music cognition. The memory system that enables humans to and (ii) auditory WM differs between stimuli maintain and manipulate information for short that can be internally rehearsed (words, tones) periods of time has been referred to as working and stimuli that are more difficult to rehearse memory (WM). Our understanding of auditory (timbre). Therefore, to further our understanding WM and whether there are differences for the of the underlying processes of WM for different Downloaded by [Barbara Tillmann] at 13:10 08 April 2013 processing of different auditory materials (e.g., auditory information, we compared, to our speech and music) is still elusive. Previous find- knowledge for the first time, WM performance ings suggest that auditory WM is not a unitary for verbal (words) and non-verbal (pitch, timbre) system (e.g., Berz, 1995; Pechmann & Mohr, materials in a forward (Experiment 1) and a 1992; Schulze, Zysset Mueller, Friederici, & backward (Experiment 2) recognition task, and Koelsch, 2011). Our present study set out to in a backward recognition task using articulatory investigate whether (i) the phonological loop, a suppression (Experiment 3). WM component known to process verbal infor- In the following we will review what is known mation (Baddeley, 2012), is also processing non- about WM for verbal, tonal, and timbre stimuli. verbal auditory information (tones and timbre) Whereas verbal WM studies have used both recall Address correspondence to: Katrin Schulze, Developmental Cognitive Neuroscience Unit, UCL Institute of Child Health, 30 Guilford Street, London WC1N 1EH, UK. E-mail: [email protected] This research was supported by a grant from the Agence Nationale de la Recherche of the French Ministry NT05-3_45978 ‘‘Music and Memory’’. We would like to thank Carine Signoret and Etienne Gaudrain for their help with recording and modifying the auditory stimuli. # 2013 Taylor & Francis 378 SCHULZE AND TILLMANN and recognition to investigate participants’ WM rehearsal being comparable to subvocal speech, performance, experiments exploring WM for non- even though some research suggested the addi- verbal materials (tones and timbre) have been tional influence of other word characteristics (i.e., relying on recognition tasks (but see Williamson, phonological complexity) and attentional me- Baddeley, & Hitch, 2010 for a tonal WM recall chanisms (Lewandowsky & Oberauer, 2008). task). Second, it has been shown that the articulatory While various short-term memory (STM) or rehearsal process can be interrupted by articula- WM models have been proposed (for overviews tory suppression (Baddeley, 1992, 2003; Hall & see Baddeley, 2012; Cowan, 1988, 1999; Ericsson Gathercole, 2011; Schendel & Palmer, 2007), & Kintsch, 1995; Jones, 1993; Nairne, 1990), our which prevents the internal rehearsal of verbal present paper is based on the Baddeley and Hitch material and thus reduces verbal WM capacity. (1974) WM model, which has motivated numer- Third, recent neuroimaging studies have provided ous studies investigating WM for verbal and tonal further evidence for subvocal rehearsal under- materials (Baddeley & Hitch, 1974; Berz, 1995; lying verbal WM. Using a recognition paradigm Hickok, Buchsbaum, Humphries, & Muftuler, these studies have reported that active rehearsal 2003; Koelsch et al., 2009; Pechmann & Mohr, of verbal material engages motor-related areas, 1992; Schendel & Palmer, 2007; Schulze, Zysset which are usually involved in controlling and et al., 2011; Williamson et al., 2010). In addition, programming of speech movements (Baddeley, although parts of this model are still under 2003; Gruber & von Cramon, 2003; Hickok et al., debate, no other verbal WM component is as 2003; Koelsch et al., 2009; Paulesu, Frith, & well investigated and accepted as the phonologi- Frackowiak, 1993; Schulze, Zysset et al., 2011; cal loop (Buchsbaum & D’Esposito, 2008). Smith & Jonides, 1997). Thus participants might use their knowledge of how to produce speech in order to convert the auditorily presented verbal information into internally rehearsable motor VERBAL INFORMATION representations or sensorimotor codes (Hickok et al., 2003; Koelsch et al., 2009; Schulze, Zysset In the influential multi-component WM model et al., 2011). proposed by Baddeley and Hitch (1974) verbal Auditory WM has mainly been investigated information is processed by a phonological loop, using verbal stimuli. Non-verbal auditory infor- which is further subdivided in a passive storage mation, however, like music, also unfolds over component (phonological store) and an active time, and the understanding and appreciation of rehearsal mechanism (articulatory rehearsal pro- music depends, as the understanding of speech, on cess). The passive storage component is assumed WM. to store auditory or speech-based information for a few seconds (Baddeley, 1992). Downloaded by [Barbara Tillmann] at 13:10 08 April 2013 When verbal information has to be maintained TONES for longer time spans, it is rehearsed by the 1 articulatory rehearsal process (Baddeley, 2003). In contrast to studies showing the improvement of The following three effects have been interpreted verbal WM performance thanks to internal re- to support the notion that the articulatory re- hearsal (for a review see Baddeley, 2003), studies hearsal is comparable to subvocal speech. First, that have investigated whether internal rehearsal the word length effect refers to the phenomenon of the to-be-remembered stimuli can also improve that participants show a greater memory span WM for tones in recognition tasks yielded con- (Baddeley, Thomson, & Buchanan, 1975) and flicting results. Some studies showed no beneficial superior recognition accuracy (Baddeley, effects of internal rehearsal for WM of tones Chincotta, Stafford, & Turk, 2002) for short words (Demany, Montandon, & Semal, 2004; Kaernbach than for long words. This finding has been used as & Schlemmer, 2008). In these studies participants one of the major arguments for articulatory might have encountered difficulties in covertly rehearsing the experimental stimuli because the 1 Refreshing in order to maintain information in WM frequency of the tones used did not correspond