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Imagining music and spatial rotation

1 2 Abstract 3 4 5 6 We report two experiments exploring whether imagining music improves spatial rotation via 7 8 increases in arousal and mood levels (Schellenberg, 2005). To aid their imagination, 9 10 participants were given instructions (none, basic or detailed) and lyrics (present or absent). 11 12 13 Experiment 1 showed no effect of instructions or lyrics on performance although participants 14 15 felt that the presence of the lyrics helped. Experiment 2 was identical to Experiment 1 except 16 17 18 that the participants were musicians (as evidenced by musical experience and/or 19 20 qualification). This time there was a significant effect of instructions in that those who 21 22 23 received the detailed instructions performed significantly better than the no instruction 24 25 condition although the presence of lyrics did not help. Further research is required to 26 27 28 establish the similarity of the imagination to the traditional arousal and mood effect but the 29 30 phenomenon may be useful for short-term boosts in spatial rotation activities. 31 32 33 34 35 36 37 142 words 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 1 63 64 65 Imagining music and spatial rotation

1 2 Music is intricately entwined with human culture as evidenced by the use of our vocal 3 4 5 apparatus and instruments dating back thousands of years (Brown, Merker, & Wallin, 2000). 6 7 In more recent times, music has been shown to have a variety of effects on our behaviour. For 8 9 10 example, in the area of retail, fast-tempo increases customers’ positive 11 12 mood and the number of items they buy (Milliman, 1982) as well as producing a faster waiter 13 14 service (Milliman, 1986). This tempo of music also results in faster driving speed and a 15 16 17 greater number of traffic violations (Brodsky, 2002). Amongst teenagers, exposure to sexual 18 19 content in music is associated with greater sexual activity and risk of engaging in early sexual 20 21 22 intercourse (Brown, L'Engle, Pardun, Guo, Kenneavy, & Jackson, 2006). On a more positive 23 24 note, listening to an excerpt of Vivaldi’s ‘Four Seasons’ led to a positive outcome on older 25 26 27 adults’ working (Mammarella et al. 2007), Alzheimer’s patients who listened to 28 29 Vivaldi’s ‘Spring Movement’ showed an increase in autobiographical (Irish et al. 30 31 2006) and cancer patients’ mood improved from listening to music (Cassileth, Vickers, & 32 33 34 McGill, 2003). However, recent research shows that concurrent listening to music and task 35 36 engagement is detrimental to performance as it produces the irrelevant sound effect – the 37 38 39 reduction in short-term memory performance in the presence of background sound (Perham 40 41 & Sykora, 2012; Perham & Vizard, 2010). 42 43 44 45 Perhaps the most famous example of the impact of music on human behaviour gained 46 47 prominence in the early 1990s with the publication of Rauscher, Shaw, and Ky’s (1993) 48 49 paper in the prestigious science journal, Nature. They observed that participants’ spatial 50 51 52 awareness abilities (as measured by the paper folding and cutting task) was better when 53 54 participants had been listening to Mozart’s Sonata for Two Pianos in D Major (K.488) for ten 55 56 57 minutes compared to listening to a relaxation tape or sitting in silence, although the effects 58 59 only lasted for ten to fifteen minutes. The increase in performance on the spatial awareness 60 61 62 2 63 64 65 Imagining music and spatial rotation

task was explained at the time by the already-founded trion model of cerebral cortex (Leng & 1 2 Shaw, 1991). This stated that the process of listening to music created a pattern of firing 3 4 5 neurons that was similar to the pattern created when performing spatial-temporal tasks (Jones 6 7 et al., 2006). It was thought that listening to Mozart activated this neural pattern, and so the 8 9 10 neurons were already firing when participants started their spatial reasoning task which 11 12 caused an increase in performance. However, as Husain et al. (2002) later pointed out, this 13 14 15 priming explanation was fundamentally flawed in that priming tended to happen when both 16 17 stimuli were related – such as facilitatory recall of the colour word “red” whilst having been 18 19 presented with the word “blood” compared to having been presented with the word “snow”. 20 21 22 Further, the similarity between either the content or processing of the spatial awareness task 23 24 and the music itself is currently unspecified. A meta-analysis of other studies exploring the 25 26 27 Mozart effect revealed little evidence for it (Chabris et al., 1999). Later, Schellenberg and 28 29 colleagues proposed the arousal-and-mood hypothesis based on an increase in the 30 31 32 participant’s mood and arousal levels due to listening to music that they prefer. For example, 33 34 spatial rotation performance increased following listening to Schubert (Nantais & 35 36 37 Schellenberg, 1999) and, in children, listening to more contemporary music like Blur 38 39 (Schellenberg & Hallam, 2005). Interestingly, the increase was not restricted to music as 40 41 participants who preferred listening to a narrated Stephen King story revealed a ‘Stephen 42 43 44 King effect’ (Nantais & Schellenberg, 1999). 45 46 As well as actively listening to music, humans also hear or imagine music in their 47 48 49 minds. In some instances this music can become quite annoying as sometimes they become 50 51 ‘stuck’ – known as ‘’ (Beaman, 2010). Further, research has shown that the 52 53 54 auditory cortex, which is activated through music, can also be activated through just 55 56 imagining it (King, 2006). Given our ability to imagine music, would it be possible to elicit 57 58 the mood and arousal effect purely by imagining music? The importance of such a curious 59 60 61 62 3 63 64 65 Imagining music and spatial rotation

finding relates to the possibility of increasing one’s spatial awareness abilities, if only for a 1 2 short period of time, which could benefit examination or work performance. 3 4 5 It is known that the imagination of a motor action produces a similar activation of the 6 7 autonomic nervous system (ANS) as the real action when measuring skin conductance 8 9 10 responses (Critchley et al., 2000; Deschaumes-Molinaro et al., 1991; Roure et al., 1998). For 11 12 example, actual participation in shooting competitions and the mental rehearsal of the same 13 14 15 task elicits similar changes skin temperature, conductance and blood flow (Deschaumes- 16 17 Molinaro et al., 1991). Similarly, other research has found that the same autonomic channels 18 19 were being used when participants were playing volleyball and when they were mentally 20 21 22 imagining the activity (Roure et al., 1998). 23 24 25 26 Imagery is simply our ability to draw upon perceptual information from our long-term 27 28 memory, and is often referred to as “seeing with the mind’s eye” (Kosslyn et al., 2001). It has 29 30 played a central role in theories of mental functioning since the time of Plato, with the 31 32 33 majority of research into mental imagery mainly concentrated on motor and visual imagery 34 35 (Smith et al. 1995). However, more recently several studies have assessed the ability of 36 37 38 , also known as the “inner ear” or the “inner voice” (Aleman et al., 2000). 39 40 The ability of auditory imagery is the subjective experience of hearing in the absence of 41 42 43 external auditory stimulation, in other words hearing in the absence of sound. Auditory 44 45 imagery appears in a variety of forms such as silent reading, speech perception, auditory 46 47 48 hallucinations in schizophrenia and in conversations with spiritual beings, earworms and 49 50 most relevant to this study, musical imagery (Barrett & Etheridge, 1992; Beaman, 2000; 51 52 Harley, 2010; Kraemer et al., 2005; Luckoff, 2007; McGuire, Silbersweig, Wright, Murray, 53 54 55 Frackowiak, & Frith, 1996). 56 57 58 59 60 61 62 4 63 64 65 Imagining music and spatial rotation

For example, Kraemer et al. (2005) monitored participants using an fMRI scanner and 1 2 asked them to passively listen to excerpts of familiar songs such as ‘Satisfaction’ by The 3 4 5 Rolling Stones and The Pink Panther theme tune as well as other less familiar songs. At 6 7 numerous points throughout the songs, short sections (2 to 5 seconds long) were removed and 8 9 10 replaced with silence. During these excerpts of silence, participants’ neural activities were 11 12 monitored, showing greater activation in the auditory cortex during the gaps of silence in 13 14 15 familiar songs than non-familiar songs. Further evidence that the auditory cortex was 16 17 activated in the absence of an external auditory stimulus was revealed by Halpern and 18 19 Zatorre, (1999) who asked participants to listen to excerpts of familiar songs and imagine the 20 21 22 continuation of the melodies. They found that the right auditory cortex was activated during 23 24 the imagery period after the musical excerpt. 25 26 27 28 Given the exploratory nature of the current investigation, we needed to provide every 29 30 opportunity to observe the effect. To facilitate this, two manipulations were introduced – 31 32 33 instructions and lyrics. It has been noted that during mental rehearsal of motor tasks, the 34 35 greater the quality of the mental rehearsal the greater the chances of an improvement in 36 37 38 performance (Deschaumes-Molinaro et al., 1991). We sought to enhance the quality of 39 40 participants’ auditory imagery by providing two levels of instructions. The first set of 41 42 43 instructions simply asked the participants to imagine a song that they liked in their head. A 44 45 second set of instructions built upon this request by giving more detail and help about how to 46 47 48 do this such as focusing on the instruments (see Materials and Appendix for more details). 49 50 The second manipulation focused on the written presence of the lyrics to aid imagery (Bailes, 51 52 2007). Thus, it was predicted that more detailed instructions and the presence of written 53 54 55 lyrics, either separately or in combination with detailed instructions, would elicit the greatest 56 57 improvement in spatial awareness performance compared to a control condition in which 58 59 60 participants just performed the spatial awareness task without imagining music or the 61 62 5 63 64 65 Imagining music and spatial rotation

presence of lyrics. In addition to the objective measurement of spatial awareness 1 2 performance, we were also interested in how well the participants thought the instructions 3 4 5 (basic and detailed) helped them to imagine the songs. To do this, a questionnaire was given 6 7 to participants after the experiment was completed and one question asked “How closely did 8 9 10 the imagined song mimic the real song?” for each instruction condition. 11 12 13 Experiment 1 14 15 16 17 Method 18 19 20 Participants 21 22 23 Forty-five students from a south Wales university participated for course credit with fifteen 24 25 participants allocated to each of the levels of the between variable. This comprised thirty 26 27 28 females and fifteen males, with an age range of 18 to 25. 29 30 31 Design 32 33 34 This study used a mixed design with one between independent variable of instruction type 35 36 (control condition, basic instructions and detailed instructions) and one within variable of 37 38 39 lyrics (lyrics and no lyrics) – lyrics obviously did not apply to the control condition in which 40 41 no imagination of music took place and was thus absent from the analysis of instruction type 42 43 44 and lyrics. Three dependent variables were measured. The first was correct performance 45 46 (ranging from 0-50) on a spatial rotation task (deciding whether two three-dimensional 47 48 49 shapes were identical or not) and was recorded by the researcher. The second was how well 50 51 the participant perceived their ability to imagine the song in their minds ranging from 0-10. 52 53 Finally, the third dependent variable was how well the participant thought they did on the 54 55 56 spatial rotation task. This score ranged from 0-100%. Half of participants completed the task 57 58 59 60 61 62 6 63 64 65 Imagining music and spatial rotation

with lyrics first and no lyrics second and the other half of participants completed the task in 1 2 the reverse order. 3 4 5 6 Materials 7 8 9 The computer program PsyCOG (Wyttenbach, 2006) was used to run the spatial awareness 10 11 task on a Viglen Genie with an Intel Core 2 processor running Windows XP. For each trial 12 13 the program produced two three-dimensional shapes made up of a series of cubes attached to 14 15 16 one another. The overall shapes were either the same as each other or the opposite. On each 17 18 of these trials one of the shapes would be rotated to 0˚, 30˚, 60˚, 90˚, 120˚, 150˚ or 180˚ - 19 20 21 based on Shepard and Metzler’s (1971) study. 22 23 Participants were required to mentally rotate one of the shapes and decide whether it 24 25 26 matched or reflected the second shape by pressing the relative arrow key on the computer 27 28 keyboard. After the completion of each individual trial PsyCOG provided feedback on their 29 30 31 answer by presenting the word ‘correct’ or ‘incorrect’. The program produced 140 trials, of 32 33 which 40 trials were completed as practice trials and 100 trials were completed as part of the 34 35 analysed correct responses. Trial presentation was random so it was unknown what 36 37 38 proportion of trials contained which degree of rotation and no time-out was required as 39 40 participants gave responses to all their trials (see Perham & Withey, 2012, for comparable 41 42 43 design and materials). 44 45 Although music was required for this study, no actual music was played. Participants 46 47 48 were told beforehand to arrive on the day of the study with the names of two of their 49 50 favourite songs and the printed lyrics to one of them (e.g. Pixie Lott – Broken Arrow, Red 51 52 Hot Chili Peppers – Under The Bridge, Jimi Hendrix – All Along The Watchtower, Ellie 53 54 55 Goulding – Your Song; see Appendix for full list). This was their responsibility and if they 56 57 failed to arrive with these materials they could not participate in the experiment. 58 59 60 61 62 7 63 64 65 Imagining music and spatial rotation

Three instruction sheets were created – one for each instruction condition. The control 1 2 condition instructions informed the participant that they would be completing a spatial 3 4 5 rotation task (see Procedure for more detail). The instructions for the basic and detailed 6 7 instruction conditions differed slightly from the control condition instructions regarding the 8 9 10 engagement of the participant in the imagination of music and the completion of a 11 12 questionnaire. Briefly, the basic instructions just required participants to imagine music they 13 14 15 liked whereas the detailed instructions asked participants to think more intensely about the 16 17 music they were going to imagine, by providing cues to invoke thoughts about the music that 18 19 they may not have considered beforehand (see Appendix for complete instructions). These 20 21 22 varied from cues that addressed the musicality of the song, such as bringing attention to the 23 24 melody, the instruments used, and the tempo, to more subjective feelings about the music, 25 26 27 such as which parts of the song were their favourite, and focusing on how the song made 28 29 them feel. 30 31 32 33 Due to the repetitive nature of the study (each participant completed two sets of 34 35 spatial rotation trials under two conditions), it was possible that arousal increase in the first 36 37 condition could affect performance during the second condition. To minimise this, a filler 38 39 40 task was used, in the form of a word search, which was designed to take participants no more 41 42 than 5 minutes to complete. 43 44 45 46 To address the issue of ‘knowing’ if participants were engaging in the task of auditory 47 48 imagination, a questionnaire was designed (see Appendix). There were 11 questions of which 49 50 ten used a 7-point Likert scale and were seeking information on how well the participant felt 51 52 53 they had engaged in the task and the impact they felt the instructions and lyrics had on their 54 55 ability to mentally imagine the song –for example, how well they felt they had imagined the 56 57 58 song, how many times they went through the song, and how useful and helpful they felt the 59 60 lyrics were. Question 8 asked how closely participants thought their auditory imagery of the 61 62 8 63 64 65 Imagining music and spatial rotation

song mimicked the real song. This question was key to the study as it provided a subjective 1 2 view on how well participants felt they had imagined the song in relation to the real song. 3 4 5 This suggested that the higher they rated their imagery on this question the greater its quality, 6 7 which should lead to a more improved score on the spatial rotation task. This question was 8 9 10 concealed among the other questions to reduce any speculation about the aim of the study. 11 12 The 11th question was a scale from 0% to 100%, which asked for the participants’ subjective 13 14 15 opinion on how well they felt they had done. Each participant completed two questionnaires, 16 17 after each block of spatial rotation trials. 18 19 20 Procedure 21 22 23 24 All participants, regardless of which condition they were allocated to, were told to try to 25 26 avoid listening to music just prior to taking part in the experiment to minimise any increases 27 28 29 in arousal due to listening to music rather than imagining music that would occur during the 30 31 experiment. Upon arrival, participants were randomly allocated to one of the three conditions 32 33 and directed to a small, quiet room/laboratory where they were tested individually or in pairs 34 35 36 (facing away from each other and two researchers were present also). Although each 37 38 participant arrived with two songs of their choice and the lyrics to one of them, only those 39 40 41 allocated to the basic or detailed instruction conditions actually used them. 42 43 44 All participants read through the appropriate instructions which informed them that 45 46 they would complete 40 practice trials of spatial rotation followed by two blocks of 50 trials 47 48 49 each. Those in the basic and detailed instructions conditions were additionally told that they 50 51 would be imagining music and using lyrics to aid them to do this depending upon which 52 53 54 condition they were in. Before the experiment started proper, participants completed some 55 56 demographic information on their response form. In between the practice session and the first 57 58 59 experimental block of trials, participants were told to sit in silence for 5 minutes while the 60 61 62 9 63 64 65 Imagining music and spatial rotation

researcher waited outside the room. Those in the basic and detailed instruction conditions 1 2 imagined music whereas those in the control condition were not given any instructions to do 3 4 5 anything. Half of these participants were able to use the lyrics they had brought in to help 6 7 them and the other half were not. Once the 5 minutes was over the experimenter re-entered 8 9 10 the room and the participants were asked to start the spatial rotation task. The participants’ 11 12 correct and incorrect answers were recorded on their answer sheet by the researcher (who was 13 14 15 seated for enough away from the participant so as not to increase their arousal but close 16 17 enough to be able to see the responses on the screen) until the participant had completed 50 18 19 trials. Next they were told they were being given 5 minutes to complete the word search filler 20 21 22 task. This was timed by the researcher who stayed in the room. Prior to commencement of the 23 24 second block of spatial rotation tasks, those in the control condition were again left alone for 25 26 27 5 minutes and those in the basic and detailed instruction conditions were told to imagine 28 29 music – once again the researcher left the room. Those had used the lyrics they had brought 30 31 32 in for the first block of spatial rotation trials were now unable to use them and those who had 33 34 not previously used them were now able to. 35 36 37 Results 38 39 40 Data was collected for all 45 participants, and all participants completed 100 trials of the 41 42 spatial rotation task of which each trial was marked as correct or incorrect, and their overall 43 44 45 score represented the total correct trials. Analyses of variance were conducted on these 46 47 correct scores as well as the question 8 from the questionnaire (How closely did the imagined 48 49 song mimic the real song?) and participants’ subjective estimation of the percentage of trials 50 51 52 they correctly solved. Finally, correlations were conducted between objective and subjective 53 54 scores for the instruction conditions. 55 56 57 58 59 60 61 62 10 63 64 65 Imagining music and spatial rotation

Correct Scores 1 2 3 Figure 1. Mean percentage of correct responses for each instruction type (control, basic or 4 5 detailed) 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 From Figure 1 it can be seen that the detailed instruction condition had the highest mean 31 32 overall score. The basic instruction condition scored slightly less on average, followed by the 33 34 control condition, which scored the lowest in comparison. A one-way between subjects 35 36 37 ANOVA revealed that there was no significant effect of instruction type on correct score, 38 39 F(2, 42) = .15, MSE = 16.02, η2 = .01, p > .05. 40 41 42 43 To explore whether the presence or absence of lyrics interacted with the instruction 44 45 type, the control condition was removed. Figure 2 shows, for both instruction conditions, that 46 47 48 the mean score for the absence of lyrics was greater than the mean score for the presence of 49 50 lyrics, with the greatest difference in the complex instruction condition. 51 52 53 Figure 2. Mean percentage of correct responses by lyrics (presence or absence) and 54 55 56 instruction type (basic or detailed) 57 58 59 60 61 62 11 63 64 65 Imagining music and spatial rotation

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 A two-way mixed subjects ANOVA showed no main effect of lyrics, F(1, 28) = .32, MSE = 22 23 4.27, η2 = .01, p > .05, no main effect of instructions, F(1, 28) = .06, MSE = 4.27, η2 = .02, p 24 25 2 26 > .05, and no significant lyrics by instructions interaction, F(1, 28) = .25, MSE = 3.27, η = 27 28 .01, p > .05. 29 30 31 32 Mimic Question 33 34 Question 8 in the questionnaire asked the participants how well they felt they had mimicked 35 36 37 the real song during the auditory imagery task in order to ascertain whether they felt the 38 39 instruction procedures and the presence of lyrics had actually worked. The question had a 40 41 42 maximum score of seven. The mean scores for participants in the basic instruction condition 43 44 with lyrics and without lyrics, and the complex instruction condition with lyrics and without 45 46 47 lyrics were all above four which is greater than 50%. One sample t-tests on all conditions 48 49 revealed that these scores were significantly different from 0, suggesting the participants 50 51 52 subjectively felt they were achieving auditory imagination (basic with lyrics, F(14) = 20.19, p 53 54 < .001; basic with no lyrics, F(14) = 10.69, p < .001; detailed with lyrics, F(14) = 27.5, p < 55 56 .001; detailed no lyrics, F(14) = 17.67, p < .001). It can be seen from Figure 3 that the 57 58 59 presence of lyrics had a greater mean score on the mimic question compared to no lyrics for 60 61 62 12 63 64 65 Imagining music and spatial rotation

both instruction conditions. The complex instruction condition scored higher on question 8 1 2 with the lyrics compared to the basic instruction condition, with the same pattern showing for 3 4 5 no lyrics. 6 7 8 Figure 3. Mean scores for Question 8 (How closely did the imagined song mimic the real 9 10 11 song?) by lyrics (presence or absence) and instruction type (basic or detailed) 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 A two-way mixed subjects ANOVA revealed a significant main effect of lyrics, F(1, 28) = 36 37 2 38 19.9, MSE = 18.15, η = .42, p < .01, with the presence of lyrics making participants feel that 39 40 the music they imagined closely resembled the music they chose. No significant main effect 41 42 of instructions was observed, F(1, 28) = 1.92, MSE = 3.75, η2 = .06, p > .05, nor was there 43 44 2 45 was a significant lyrics by instructions interaction, F(1, 28) = .9, MSE = .82, η = .03, p > .05. 46 47 48 Performance estimate 49 50 51 A final question in the questionnaire asked participants how well they thought they 52 53 54 performed in the imagination conditions by providing an estimate of their correct percentage. 55 56 A two-way mixed subjects ANOVA revealed no significant main effect of lyrics, F(1, 28) = 57 58 2 59 .16, MSE = 12.15, η = .01, p > .05, no significant main effect of instructions, F(1, 28) = .55, 60 61 62 13 63 64 65 Imagining music and spatial rotation

MSE = 370.02, η2 = .02 p > .05, and no significant lyrics by instructions interaction, F(1, 28) 1 2 = .12, MSE = 8.82, η2 = 0, p > .05. 3 4 5 6 Figure 4. Mean correct percentage performance estimates by lyrics (presence or absence) and 7 8 instruction type (basic or detailed) 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 Correlations between subjective and objective performance for each condition 34 35 36 Participant’s actual performance for basic instructions with lyrics, basic instructions without 37 38 lyrics, complex instructions with lyrics and complex instructions without lyrics was 39 40 41 correlated with their own estimates of how well they performed in these conditions. Only 42 43 significant positive correlations between objective and subjective performance were only 44 45 46 observed for basic instructions with lyrics, basic instructions with no lyrics and complex 47 48 instructions with no lyrics (see Table 1). However, the other positive correlation (detailed 49 50 51 instructions and no lyrics) was almost significant. 52 53 54 55 56 57 Objective and subjective, basic instructions, no lyrics r = .81, p = .000 ** 58 59 60 61 62 14 63 64 65 Imagining music and spatial rotation

Objective and subjective, basic instructions, lyrics r = .86, p = .000 ** 1 2 Objective and subjective, detailed instructions, no lyrics r = .49, p = .06 3 4 5 Objective and subjective, detailed instructions, lyrics r = .63, p = .01 ** 6 7 ** Correlation was significant at the 0.01 level (two-tailed) 8 9 10 11 * Correlation was significant at the 0.05 level (two-tailed) 12 13 14 15 16 17 Table 1. Pearson’s product-moment correlations and p-values for objective and subjective 18 19 20 performance across conditions 21 22 23 In sum, as the complexity of instruction type increased from control to basic to 24 25 26 detailed, increases in mean scores were seen but were not significant. The presence of lyrics 27 28 showed no significant increase in mean scores compared to no lyrics. With regards to the 29 30 participants’ subjective beliefs that they were able to mimic the songs, participants felt that 31 32 33 the presence of lyrics significantly improved their ability to imagine the songs. Estimated 34 35 performance was roughly equivalent regardless of the instruction condition and the presence 36 37 38 of lyrics. Finally, there were positive relationships between objective and subjective estimates 39 40 of performance across all conditions with three being significant. 41 42 43 44 Experiment 2 45 46 47 Experiment 1 showed that the presence of instructions (basic or detailed) had no effect on 48 49 spatial rotation performance. Further, the presence of lyrics to aid musical imagination did 50 51 52 not significantly improve performance either. One explanation why no effect of instructions 53 54 was found may be due to the (in)ability of participants to imagine music in their heads. As far 55 56 57 as we were aware, none of the participants were musicians yet research suggests that 58 59 musicians are best equipped to perform such musical imagery. For example, musically- 60 61 62 15 63 64 65 Imagining music and spatial rotation

trained participants were superior to non-musically trained participants at being able to 1 2 decide, through musical imagery, which of the presented familiar lyrics was in a higher or 3 4 5 lower pitch (Aleman et al., 2000). Bailes (2007) investigated the use of musical imagery in 6 7 the everyday lives of music students. Through using experienced sampling methods (ESM) 8 9 10 Bailes assessed when and potentially why they performed musical imagery. The results 11 12 showed that the participants reported ‘musical imagery episodes’ on a daily basis, with the 13 14 15 most prominent features of imagery episodes being lyrics. Participants believed the reason 16 17 behind imagining the songs they did was due to either hearing or performing them recently. 18 19 Bailes proposed that the more a person was exposed to a specific song, the more they were 20 21 22 likely to imagine music. This suggests that as musicians are more likely to rehearse and listen 23 24 to music then they are probably better at musical imagery than non-musicians. Thus, 25 26 27 Experiment 2 repeated Experiment 1 but this time using participants who were musicians as 28 29 evidenced by a minimum of Grade 3 accomplishment in their chosen instrument or a GCSE 30 31 32 in music. 33 34 35 Method 36 37 38 Participants 39 40 41 42 Participants comprised forty five musicians from a variety of different musical groups such as 43 44 orchestras including string and symphony orchestras, music societies specifically jazz and 45 46 several rock bands, based in and around the south Wales area. This included 28 males and 17 47 48 49 females with an age range of 18-79. All participants had been playing their chosen instrument 50 51 for at least three years with experience ranging from 3 to 71 years and had attained at least 52 53 54 Grade 3 in their chosen instrument or a GCSE – qualifications ranged from Grade 3 to Grade 55 56 8 and from GCSE to Degree level. 57 58 59 60 Design 61 62 16 63 64 65 Imagining music and spatial rotation

The Design was identical to that in Experiment 1. 1 2 3 Materials 4 5 6 7 The Materials were identical to those in Experiment1 with the exception of different songs 8 9 being imagined - e.g. Eminem – Stan, The Beatles – While My Guitar Gently Weeps, 10 11 Damian Rice – Cannonball, Frank Sinatra – My Way, Metallica – Enter Sandman, Michael 12 13 14 Jackson – Wanna Be Startin’ Somethin’, Rihanna – We Found Love and Stevie Wonder – 15 16 Superstition (see Appendix for full list). 17 18 19 20 Procedure 21 22 23 The same Procedure was adopted as used in Experiment 1. 24 25 26 Results 27 28 29 30 The same analyses were conducted as in Experiment 1. 31 32 33 Correct Scores 34 35 36 Figure 5. Mean percentage of correct responses for each instruction type (control, basic or 37 38 detailed) 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 17 63 64 65 Imagining music and spatial rotation

Figure 5. shows that performance was better in the detailed instructions condition followed 1 2 by the basic instructions and then the control condition. A one-way ANOVA revealed a 3 4 2 5 significant main effect of instructions, F(2, 42) = 4.3, MSE = 107.22, η = .17, p < .05. Post- 6 7 hoc Bonferroni tests showed that only the detailed and control conditions were significantly 8 9 10 different from each (p < .05) with performance being greater in the detailed condition. 11 12 13 Figure 6. Mean percentage of correct responses by lyrics (presence or absence) and 14 15 instruction type (basic or detailed) 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 A two-way mixed subjects ANOVA revealed no significant main effect of lyrics, F(1, 28) = 41 42 .34, MSE = 2.02, η2 = .01, p > .05, no significant main effect of instructions, F(1, 28) = 3.49, 43 44 2 45 MSE = 190.82, η = .11, p > .05, and no significant lyrics by instructions interaction, F(1, 28) 46 47 = .03, MSE = .15, η2 = 0, p > .05. 48 49 50 51 Mimic Question 52 53 Figure 7. Mean scores for Question 8 (How closely did the imagined song mimic the real 54 55 56 song?) by lyrics (presence or absence) and instruction type (basic or detailed) 57 58 59 60 61 62 18 63 64 65 Imagining music and spatial rotation

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 One sample t-tests on all conditions revealed that these scores were significantly different 22 23 24 from 0, suggesting the participants subjectively felt they were achieving auditory imagination 25 26 (basic with lyrics, F(14) = 14.1, p < .001; basic with no lyrics, F(14) = 16.36, p < .001; 27 28 detailed with lyrics, F(14) = 20.74, p < .001; detailed no lyrics, F(14) = 13.48, p < .001). A 29 30 31 two-way mixed subjects ANOVA revealed a significant main effect of lyrics, F(1, 28) = 17.6, 32 33 MSE = 12.15, η2 = .39, p < .01, in which the presence of lyrics made the participants feel that 34 35 36 the imagined music closely resembled the songs they chose, but no significant main effect of 37 38 instructions, F(1, 28) = .09, MSE = .15, η2 = .09, p > .05. Finally, no significant lyrics by 39 40 2 41 instructions interaction was observed, F(1, 28) = 2.92, MSE = 2.02, η = .09, p > .05. 42 43 44 Performance estimate 45 46 47 Figure 8. Mean correct percentage performance estimates by lyrics (presence or absence) and 48 49 50 instruction type (basic or detailed) 51 52 53 54 55 56 57 58 59 60 61 62 19 63 64 65 Imagining music and spatial rotation

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 A two-way mixed subjects ANOVA revealed no significant main effect of lyrics, F(1, 28) = 25 26 2 27 3.11, MSE = 60, η = .01, p > .05, no significant main effect of instructions, F(1, 28) = .35, 28 29 MSE = 26.67, η2 = .01, p > .05, and no significant lyrics by instructions interaction, F(1, 28) = 30 31 2 32 0, MSE = 0, η = 0, p > .05. 33 34 35 Correlations between subjective and objective performance for each condition 36 37 38 Participant’s actual performance for basic instructions with lyrics, basic instructions without 39 40 41 lyrics, complex instructions with lyrics and complex instructions without lyrics was 42 43 correlated with their own estimates of how well they performed in these conditions. The only 44 45 46 significant correlation was the positive correlation for detailed instructions with lyrics (see 47 48 Table 2). However, the other correlations were also positive and two were close to 49 50 significance. 51 52 53 54 Objective and subjective, basic instructions, no lyrics r = .42, p = .12 55 56 Objective and subjective, basic instructions, lyrics r = .49, p = .07 57 58 59 Objective and subjective, detailed instructions, no lyrics r = .55, p = .03 * 60 61 62 20 63 64 65 Imagining music and spatial rotation

Objective and subjective, detailed instructions, lyrics r = .5, p =.06 1 2 3 ** Correlation was significant at the 0.01 level (two-tailed) 4 5 6 * Correlation was significant at the 0.05 level (two-tailed) 7 8 9 10 11 12 Table 2. Pearson’s product-moment correlations and p-values for objective and subjective 13 14 15 performance across conditions 16 17 18 In sum, the pattern of data was similar to that observed in Experiment 1: there was an 19 20 21 increase in spatial rotation performance as the complexity of the instructions (none, basic, 22 23 detailed) increased. However, this time a significant difference was observed between the 24 25 26 control and detailed instructions conditions showing that, compared to no auditory imagery, 27 28 spatial rotation performance was significantly improved when participants were instructed to 29 30 imagine the music in great detail. The presence of lyrics again showed no improvement on 31 32 33 performance. As with Experiment 1, participants once again felt that the presence of lyrics 34 35 enabled them to imagine the song better. Estimated performance did not differ between 36 37 38 instructions conditions or the presence or absence of lyrics, and neither did these variables 39 40 interact with each other. Finally, although there were positive relationships between objective 41 42 43 and subjective estimates of performance across all conditions, only one was significant 44 45 (detailed instructions with no lyrics). 46 47 48 Discussion 49 50 51 52 Two experiments explored whether just using musical imagery could elicit the mood and 53 54 arousal effect on spatial rotation performance by giving participants basic or detailed 55 56 57 instructions to aid them with this imagery and allowing them to read the lyrics to the song 58 59 they imagined. Experiment 1 showed no effect of instructions on spatial rotation 60 61 62 21 63 64 65 Imagining music and spatial rotation

performance. Experiment 2 repeated Experiment 1 but used musicians (as evidenced by 1 2 number of years of experience and/or musical qualification) and showed the same pattern in 3 4 5 performance. More importantly was the observation of a significant difference between the 6 7 control and detailed instructions condition. Use of lyrics did not have an effect on 8 9 10 performance in either experiment. However, participants felt that the presence of lyrics 11 12 significantly enabled them to imagine the music. Further, in general, there was a positive 13 14 15 relationship between objective spatial rotation performance and subjective, estimated 16 17 performance across all conditions. 18 19 20 Listening to music is well known to have beneficial effects on a variety of factors 21 22 23 (Cassileth et al., 2003; Rickard et al., 2005; Siedlecki & Good, 2006,) and one of the most 24 25 publicised has been the mood and arousal effect. Previously known as the ‘Mozart effect’, it 26 27 28 is the interesting phenomenon whereby listening to music (or engaging in any positive 29 30 activity, Schellenberg, 2005) that one likes improves spatial rotation performance via the 31 32 33 mechanism of elevating mood and arousal levels (Nantais & Schellenberg, 1999). The current 34 35 experiments sought to replicate this purely through musical imagery – that is, by asking 36 37 participants to simply imagine, rather than listen, to their preferred music. Only musicians 38 39 40 (Experiment 2) improved their spatial rotation performance after reading detailed instructions 41 42 on how to do so. 43 44 45 Although it is known that imagination of an action can create similar motor responses 46 47 as the actual motoric action (Deschaumes-Molinaro et al., 1991; Roure et al., 1998) and that 48 49 50 imagining music elicits the same neural activity as actually listening to music (Halpern & 51 52 Zatorre, 1999; Kraemer et al., 2005), the current study, as far as the current authors are aware, 53 54 provides the first instance demonstrating that the mood and arousal effect can be elicited 55 56 57 purely by imagining music. Potential benefits relate to improving spatial rotation 58 59 performance in certain occupations (e.g. architecture, artist, graphic designer, athletics), 60 61 62 22 63 64 65 Imagining music and spatial rotation

academic disciplines (e.g. art, design, mathematics, sports) that require the manipulation of 1 2 spatially-related objects. However, it is unknown how long this improvement to spatial 3 4 5 functioning lasts. It is quite likely that it would not last any longer than the fifteen minutes 6 7 attributed to the mood and arousal effect (Rauscher et al., 1993). Further, it may also affect 8 9 10 tasks requiring processing speed or creativity (Schellenberg, 2005) or even infants’ 11 12 performance on short-term cognitive tasks (Shenfield, Trehub, & Nakata, 2003). 13 14 15 It seems that the use of the more detailed instructions did improve the quality of 16 17 musical imagery as suggested by the greater performance in this condition. Thus, asking 18 19 participants to focus on aspects of the musical composition such as what instruments were 20 21 22 present, how the song started, what the melody and tempo were like as well as how it made 23 24 them feel, allowed the experienced musician to more effectively imagine what the music 25 26 27 sounded like and, theoretically, increased their mood and arousal levels (Nantais & 28 29 Schellenberg, 1999; Schellenberg, 2005). Further confirmation of this could come from mood 30 31 32 ratings and physiological changes in electrodermal activity. 33 34 35 It may be suggested that participants’ arousal levels could have been increased due to 36 37 the presence of the researchers in the laboratory to record participants’ responses (PsyCOG 38 39 40 did not record the responses unfortunately). This is possible although we tried to ensure that 41 42 researchers were as unobtrusive as possible by being out of sight and participants seemed to 43 44 45 be fully engaged in the task at all times. As this procedure occurred for all conditions, it is 46 47 unlikely to have been the cause of any differences between the two experiments. A similar 48 49 50 methodology has been employed previously in two studies where mood inductions took place 51 52 with the researcher present in the room. In both cases, the presence of the researcher did not 53 54 adversely affect participants in the control condition as measured by state anxiety (Perham & 55 56 57 Oaksford, 2006; Perham & Rosser, 2012). 58 59 60 61 62 23 63 64 65 Imagining music and spatial rotation

The current findings lend further support to the notion that the mood and arousal 1 2 effect cannot be restricted to music by Mozart or other classical musicians. As with Perham 3 4 5 and Withey (2012), participants were allowed to choose whichever music they preferred and 6 7 their choices covered a range of genres such as thrash metal, soul, dance and pop. According 8 9 10 to Schellenberg (2005), the same effect should be observed with other activities that increase 11 12 mood and arousal such as listening to music without lyrics, giving participants a hot beverage 13 14 15 or a small bag of sweets (e.g. Isen, 2000; Smith, Osborne, Mann, Jones, & White, 2004). 16 17 The fact that musicians improved their spatial rotation performance following the 18 19 detailed instructions whereas non-musicians (we assume) did not, may reignite the debate 20 21 22 regarding music and, more specifically, the qualities of music, being responsible for the effect 23 24 (see Hetland, 2000). The main argument against the (imagined) music priming spatial 25 26 27 rotation performance comes from the fact that priming tends to occur when both the prime 28 29 and the target share some stimulus similarity. However, it is currently unclear what this 30 31 32 similarity is supposed to be in the mood and arousal effect. Further, if, as Schellenberg (2005) 33 34 argues, other activities are able to boost mood and arousal and thus produce the same effect, 35 36 37 then it would be even more inconceivable that priming would be an adequate explanation. 38 39 The fact that only musicians showed the effect may suggest that their increased ability to 40 41 imagine music increased their mood and arousal more than non-musicians. 42 43 44 45 One might suggest that participants were able to deduce the purpose of the study and 46 47 therefore responding accordingly. That is, by realizing that the use of imagined music was 48 49 50 likely to increase spatial rotation performance participants may have tried harder when they 51 52 were asked to imagine the music. Two points would refute this. Firstly, as it was a between 53 54 groups design, each participant was only privy to one condition and so never had the 55 56 57 opportunity to adjust their spatial rotation performance in accordance with the condition. 58 59 Secondly, given that two conditions required participants to imagine the music it would be 60 61 62 24 63 64 65 Imagining music and spatial rotation

expected that both of those would show significantly greater performance compared to the 1 2 control condition whereas only the detailed instructions showed this. 3 4 5 6 Obviously this was an exploratory set of experiments with a rather rudimentary (albeit 7 8 successful) set of instructions on how to imagine the music. A number of issues could be 9 10 11 explored in the future such as exactly how much improvement could be gained with better 12 13 instructions and/or imagination, how long the effect lasts, and whether non-musicians could 14 15 be trained to imagine music as effectively as musicians. 16 17 18 19 In summary, we show that imagining music reveals improvements to spatial rotation 20 21 in musicians only. Although non-musicians showed the same increase, it was not significant. 22 23 24 We believe that this is the first demonstration of this effect and it may prove beneficial for 25 26 individuals working or studying in an area where the manipulation of spatial information is a 27 28 29 key requirement. 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 25 63 64 65 Imagining music and spatial rotation

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