- Email: [email protected]
Congenital amusia
Handbook of Clinical Neurology, Vol. 111 (3rd series) Pediatric Neurology Part I O. Dulac, M. Lassonde, and H.B. Sarnat, Editors © 2013 Elsevier B.V. All rights reserved
Chapter 24
Congenital amusia VICTORIA J. WILLIAMSON* AND LAUREN STEWART Department of Psychology, Goldsmiths, University of London, London, UK
For as long as there has been recorded history, humans have produced and listened to music. So natural is our affinity with music that it is easy to take it for granted. However, for the few percent of the population with a disorder termed congenital amusia, this natural relationship with music never fully develops (Kalmus and Fry, 1980; Ayotte et al., 2002). Individuals with congenital amusia often dislike music, describing it as “banging” or “crashing,” and find recognition of well-known melodies from their own culture very difficult. They seem to lack a sense of being “in tune,” either when listening to or producing music. Finally, they typically avoid environments where music is present and do not utilize music for mood enhancement, emotional release, or relaxation (McDonald and Stewart, 2008). Their experiences cannot be ascribed to peripheral hearing difficulties, lack of exposure during development, brain damage, or social/intellectual impairments. Although the first suspected case of congenital amusia was described at the end of the nineteenth century (Allen, 1878), the next hundred years saw only scant reports of the condition in the literature. Systematic investigation into the disorder became possible after the development of the Montreal Battery for the Evaluation of Amusia (MBEA), a standardized test that probes different aspects of musical processing and provides a means for identifying individuals with congenital amusia (“amusics” hereafter; Peretz et al., 2003). Studies that have utilized the MBEA confirm that congenital amusia is a relatively rare condition that is associated with difficulties that concern pitch; rhythm has been found to be simultaneously impaired in only around 50% of cases (Peretz et al., 2003). The disorder should not be confused with “tone deafness,” a term typically used to refer to poor pitch singing ability (Cuddy et al., 2005; Wise and Sloboda, 2008; Dalla Bella et al., 2009).
PITCH PERCEPTION DEFICITS Psychophysical tests have shown that amusics have higher than normal thresholds for the detection of a pitch change and the discrimination of pitch direction (Foxton et al., 2004; Hyde and Peretz, 2004). Thresholds for pitch direction discrimination, in particular, can often exceed one semitone (Liu et al., 2010; Williamson and Stewart, 2010; Williamson et al., 2012), the smallest interval used in Western music, with profound consequences for the encoding of more complex musical structure. Pitch direction, for instance, can be seen as a building block for the representation of contour – the pattern of ups and downs of a melody. Contour plays a key role in our encoding and retention of melodies over time (Dowling, 1978; Edworthy, 1985) and a deficit affecting pitch direction will likely limit this capacity.
MEMORY FOR MUSIC Pitch perception abilities can vary widely in congenital amusia and some individuals have thresholds in the normal range, suggesting that their musical difficulties may stem from a different underlying cause. Recent studies have revealed deficits in pitch memory which are not easily explained in terms of perceptual deficits, since the intervals used in these stimuli exceed measured thresholds (Foxton et al., 2004; Tillmann et al., 2009). The finding that these difficulties do not extend to the language domain (Tillmann et al., 2009; Williamson and Stewart, 2010) rules out any explanation based on a general short-term memory problem. A reduced ability to maintain musical sounds in memory would have implications for several other aspects of music cognition, for instance, the generation of expectancy; a factor thought to be crucial for engagement and enjoyment with music (Meyer, 1956; Huron, 2006).
*Correspondence to: Victoria J. Williamson, Psychology Department, Goldsmiths, University of London, New Cross, London SE14 6NW, UK. Tel: þ44 0207 0785316, Fax: þ44 0207 9197873, E-mail: [email protected]
238
V.J. WILLIAMSON AND L. STEWART
SPOKEN LANGUAGE COMPREHENSION An important question is whether the difficulties seen in congenital amusia transfer beyond the musical domain. One area where difficulties may be anticipated is in spoken language, where pitch plays an important role in conveying aspects of referential meaning (in tone languages), emotion, intention, and emphasis. Ayotte et al. (2002) and Patel et al. (2005) reported that amusics had little or no difficulty discriminating spoken phrases on the basis of their pitch contours alone. One reason for this may be that the pitch changes used in natural speech, like the stimuli used in these studies, are typically large (on average 5–12 semitones) and may therefore be sufficiently salient such that the majority of amusics can perceive them without difficulty. In a recent study, which required amusics and matched controls to discriminate statements and questions based on pitch contours that were more subtle (on average 4–5 semitones), amusics performed more poorly than controls (Liu et al., 2010). This finding suggests that their deficits do extend to the processing of pitch within speech but such difficulties are unlikely to manifest in everyday life, where pitch changes tend to be large and accompanied by contextual cues that would serve to prevent a breakdown in communicative comprehension.
SPATIAL REPRESENTATIONS In many cultures, there is a strong association between musical pitch and vertical space, such that notes are termed “high” or “low” depending on their relative frequency. The extent to which spatial representations are intrinsic to our ability to perceive pitch relationships in music is, as yet, unclear, though a study by Douglas and Bilkey (2007) appeared to provide evidence that was consistent with this view. These authors found that amusics performed poorly on a mental spatial rotation task (Shepard and Metzler, 1971), with the degree of impairment correlating with performance on the contour subtest of the MBEA. This result highlights the potential importance of spatial relationships in music processing, but it is clear that more evidence is needed to establish the significance and implications of these findings (Stewart and Walsh, 2007). Two more recent studies failed to replicate the relationship between amusia and mental rotation accuracy (Tillmann et al., 2010; Williamson et al., 2011) although there is evidence that some amusics exhibit longer mental rotation reaction times, a finding that correlates with pitch direction discrimination ability (Williamson et al., 2011).
NEUROBIOLOGY OFAMUSIA Congenital amusia can be conceived of as a neurodevelopmental disorder with presumed genetic origins.
A family aggregation study found an incidence of 39% in first degree relatives of probands, compared to only 3% of controls’ relatives (Peretz et al., 2007). A small number of structural imaging studies have revealed anomalies in superior temporal cortex and inferior frontal cortex of the right (Hyde et al., 2006; Hyde et al., 2007) or left (Mandell et al., 2007) hemispheres. In particular, Hyde et al. (2007) noted areas of cortical thickness in inferior frontal gyrus, which led them to suggest that congenital amusia may be characterized by abnormal neuronal migration between temporal and frontal areas. Loui et al. (2009) provided evidence to support this view, with a diffusion tensor imaging study that assessed the structural integrity of white matter tracts, in particular the arcuate fasciculus (AF) that traverses frontotemporal regions. They found that amusics had sparser AF tracts compared with controls, with the right superior tract unidentifiable in 9/10 participants. These results suggest a degree of disconnection along the fronto-temporal pathway in amusics and make the tentative prediction that any gene or sets of genes associated with the disorder may be involved in the early neural migration of neurons along this pathway (Stewart, 2008). Histological evidence shows that malformations in cortical development are also found in dyslexia (Galaburda et al., 2006) thus one possibility may be that both disorders result from aberrant neuronal migration and the differences in their behavioral manifestation relate to the particular pathways affected.
DEVELOPMENTAL TRAJECTORY All the studies reported so far have investigated congenital amusia in adults; however, the term “congenital” suggests the condition is present at birth and anecdotal reports support the notion that amusics’ difficulties with music perception and production may be present from early childhood. Mapping the clinical profile of congenital amusia in childhood would contribute to theories regarding the role of neural development in the expression of the disorder in adults and may also help to determine whether early intervention could lead to a degree of remediation. Systematic investigation of the developmental trajectory of the disorder will require the development of new diagnostic tools, since the MBEA is not currently suitable for use with children; recent studies have begun to address this issue (Lebrun et al., 2012). The employment of psycho-acoustic measures that are able to minimize age-related attentional and motivation factors would be particularly important in this regard.
CONCLUSIONS Congenital amusia is a neurodevelopmental disorder that leads to lifelong difficulties with perception and production of musical sounds. Studying congenital
CONGENITAL AMUSIA amusia gives us a unique window onto the multitude of cognitive skills that come together to allow engagement with music and demonstrates how musical behaviors relate to other complex human abilities, such as spoken language and spatial representation. Future work will determine not only the implications of the condition for individuals with congenital amusia but also allow us to better understand how genes, neural development, and behavior interact to produce an understanding and appreciation of our musical environment.
REFERENCES Allen G (1878). Note-deafness. Mind 10: 157–167. Ayotte J, Peretz I, Hyde K (2002). Congenital amusia: a group study of adults afflicted with a music-specific disorder. Brain 125: 238–251. Cuddy LL, Balkwill LL, Peretz I et al. (2005). Musical difficulties are rare: a study of ‘tone deafness’ among university students. In: G Avanzini, L Lopez, S Koelsch et al. (Eds.), The Neurosciences and Music II: From Perception to Performance. New York Academy of Sciences, New York, NY. Dalla Bella S, Gigue`re J-F, Peretz I (2009). Singing in congenital amusia. J Acoust Soc Am 126: 414–424. Douglas KM, Bilkey DK (2007). Amusia is associated with deficits in spatial processing. Nat Neurosci 10: 915–921. Dowling WJ (1978). Scale and contour: two components of a theory of memory for melodies. Psychol Rev 85: 341–354. Edworthy J (1985). Interval and contour in melody processing. Music Perc 2: 375–388. Foxton JM, Dean JL, Gee R et al. (2004). Characterization of deficits in pitch perception underlying “tone deafness”. Brain 127: 801–810. Galaburda AM, LoTurco J, Ramus F et al. (2006). From genes to behaviour in developmental dyslexia. Nat Neurosci 9: 1213–1217. Huron D (2006). Sweet Anticipation: Music and the Psychology of Expectation. The MIT Press, Cambridge. Hyde KL, Peretz I (2004). Brains that are out of tune but in time. Psychol Sci 15: 356–360. Hyde KL, Zatorre RJ, Griffiths TD et al. (2006). Morphometry of the amusic brain: a two-site study. Brain 129: 2562–2570. Hyde KL, Lerch JP, Zatorre RJ et al. (2007). Cortical thickness in congenital amusia: when less is better than more. J Neurosci 27: 13028–13032. Kalmus H, Fry DB (1980). On tune deafness (dysmelodia) – frequency, development, genetics and musical background. Ann Hum Genet 43: 369–382.
239
Lebrun MA, Moreau P, McNally-Gagnon A et al. (2012). Congenital amusia in childhood: a case study. Cortex in press. Liu F, Patel AD, Fourcin A et al. (2010). Intonation processing in congenital amusia: Discrimination, identification and imitation. Brain 133: 1682–1692. Loui P, Alsop D, Schlaug G (2009). Tone deafness: a new disconnection syndrome? J Neurosci 29: 10215–10220. Mandell J, Schulze K, Schlaug G (2007). Congenital amusia: an auditory-motor feedback disorder? Restor Neurol Neurosci 25: 323–334. McDonald C, Stewart L (2008). Uses and functions of music in congenital amusia. Music Perception 25: 345–355. Meyer LB (1956). Emotion and Meaning in Music. University of Chicago Press, Chicago. Patel AD, Foxton JM, Griffiths TD (2005). Musically tone-deaf individuals have difficulty discriminating intonation contours extracted from speech. Brain Cogn 59: 310–313. Peretz I, Champod AS, Hyde K et al. (2003). Varieties of musical disorders. The Montreal Battery of Evaluation of Amusia. In: G Avanzini, C Faienza, D Minciacchi et al. (Eds.), The Neurosciences and Music. New York Academy of Sciences, New York. Peretz I, Cummings S, Dube´ M-P (2007). The genetics of congenital amusia (Tone Deafness): A family-aggregation study. Am J Hum Genet 81: 582–588. Shepard R, Metzler J (1971). Mental rotation of three dimensional objects. Science 171: 701–703. Stewart L (2008). Fractionating the musical mind: insights from congenital amusia. Curr Opin Neurobiol 18: 127–130. Stewart L, Walsh V (2007). Music perception: sounds lost in space. Curr Biol 17: R892–R893. Tillmann B, Schulze K, Foxton JM (2009). Congenital amusia: a short-term memory deficit for nonverbal, but not verbal sounds. Brain Cogn 71: 259–264. Tillmann B, Jolicoeur P, Ishihara M et al. (2010). The amusic brain: lost in music, but not in space. Plos One 5: e10173. Williamson VJ, Stewart L (2010). Memory for pitch in congenital amusia: beyond a fine-grained pitch deficit. Memory 18: 657–669. Williamson VJ, Cocchini G, Stewart L (2011). The relationship between pitch and space in congenital amusia. Brain Cogn 76: 70–76. Williamson VJ, Liu F, Peryer G et al. (2012). Perception and action de-coupling in congenital amusia: sensitivity to task demands. Neuropsychologia 50: 172–180. Wise KJ, Sloboda JA (2008). Establishing an empirical profile of self-defined “tone deafness”: perception, singing performance and self-assessment. Musicae Scientiae 12: 3–26.
Chapter 24
Congenital amusia VICTORIA J. WILLIAMSON* AND LAUREN STEWART Department of Psychology, Goldsmiths, University of London, London, UK
For as long as there has been recorded history, humans have produced and listened to music. So natural is our affinity with music that it is easy to take it for granted. However, for the few percent of the population with a disorder termed congenital amusia, this natural relationship with music never fully develops (Kalmus and Fry, 1980; Ayotte et al., 2002). Individuals with congenital amusia often dislike music, describing it as “banging” or “crashing,” and find recognition of well-known melodies from their own culture very difficult. They seem to lack a sense of being “in tune,” either when listening to or producing music. Finally, they typically avoid environments where music is present and do not utilize music for mood enhancement, emotional release, or relaxation (McDonald and Stewart, 2008). Their experiences cannot be ascribed to peripheral hearing difficulties, lack of exposure during development, brain damage, or social/intellectual impairments. Although the first suspected case of congenital amusia was described at the end of the nineteenth century (Allen, 1878), the next hundred years saw only scant reports of the condition in the literature. Systematic investigation into the disorder became possible after the development of the Montreal Battery for the Evaluation of Amusia (MBEA), a standardized test that probes different aspects of musical processing and provides a means for identifying individuals with congenital amusia (“amusics” hereafter; Peretz et al., 2003). Studies that have utilized the MBEA confirm that congenital amusia is a relatively rare condition that is associated with difficulties that concern pitch; rhythm has been found to be simultaneously impaired in only around 50% of cases (Peretz et al., 2003). The disorder should not be confused with “tone deafness,” a term typically used to refer to poor pitch singing ability (Cuddy et al., 2005; Wise and Sloboda, 2008; Dalla Bella et al., 2009).
PITCH PERCEPTION DEFICITS Psychophysical tests have shown that amusics have higher than normal thresholds for the detection of a pitch change and the discrimination of pitch direction (Foxton et al., 2004; Hyde and Peretz, 2004). Thresholds for pitch direction discrimination, in particular, can often exceed one semitone (Liu et al., 2010; Williamson and Stewart, 2010; Williamson et al., 2012), the smallest interval used in Western music, with profound consequences for the encoding of more complex musical structure. Pitch direction, for instance, can be seen as a building block for the representation of contour – the pattern of ups and downs of a melody. Contour plays a key role in our encoding and retention of melodies over time (Dowling, 1978; Edworthy, 1985) and a deficit affecting pitch direction will likely limit this capacity.
MEMORY FOR MUSIC Pitch perception abilities can vary widely in congenital amusia and some individuals have thresholds in the normal range, suggesting that their musical difficulties may stem from a different underlying cause. Recent studies have revealed deficits in pitch memory which are not easily explained in terms of perceptual deficits, since the intervals used in these stimuli exceed measured thresholds (Foxton et al., 2004; Tillmann et al., 2009). The finding that these difficulties do not extend to the language domain (Tillmann et al., 2009; Williamson and Stewart, 2010) rules out any explanation based on a general short-term memory problem. A reduced ability to maintain musical sounds in memory would have implications for several other aspects of music cognition, for instance, the generation of expectancy; a factor thought to be crucial for engagement and enjoyment with music (Meyer, 1956; Huron, 2006).
*Correspondence to: Victoria J. Williamson, Psychology Department, Goldsmiths, University of London, New Cross, London SE14 6NW, UK. Tel: þ44 0207 0785316, Fax: þ44 0207 9197873, E-mail: [email protected]
238
V.J. WILLIAMSON AND L. STEWART
SPOKEN LANGUAGE COMPREHENSION An important question is whether the difficulties seen in congenital amusia transfer beyond the musical domain. One area where difficulties may be anticipated is in spoken language, where pitch plays an important role in conveying aspects of referential meaning (in tone languages), emotion, intention, and emphasis. Ayotte et al. (2002) and Patel et al. (2005) reported that amusics had little or no difficulty discriminating spoken phrases on the basis of their pitch contours alone. One reason for this may be that the pitch changes used in natural speech, like the stimuli used in these studies, are typically large (on average 5–12 semitones) and may therefore be sufficiently salient such that the majority of amusics can perceive them without difficulty. In a recent study, which required amusics and matched controls to discriminate statements and questions based on pitch contours that were more subtle (on average 4–5 semitones), amusics performed more poorly than controls (Liu et al., 2010). This finding suggests that their deficits do extend to the processing of pitch within speech but such difficulties are unlikely to manifest in everyday life, where pitch changes tend to be large and accompanied by contextual cues that would serve to prevent a breakdown in communicative comprehension.
SPATIAL REPRESENTATIONS In many cultures, there is a strong association between musical pitch and vertical space, such that notes are termed “high” or “low” depending on their relative frequency. The extent to which spatial representations are intrinsic to our ability to perceive pitch relationships in music is, as yet, unclear, though a study by Douglas and Bilkey (2007) appeared to provide evidence that was consistent with this view. These authors found that amusics performed poorly on a mental spatial rotation task (Shepard and Metzler, 1971), with the degree of impairment correlating with performance on the contour subtest of the MBEA. This result highlights the potential importance of spatial relationships in music processing, but it is clear that more evidence is needed to establish the significance and implications of these findings (Stewart and Walsh, 2007). Two more recent studies failed to replicate the relationship between amusia and mental rotation accuracy (Tillmann et al., 2010; Williamson et al., 2011) although there is evidence that some amusics exhibit longer mental rotation reaction times, a finding that correlates with pitch direction discrimination ability (Williamson et al., 2011).
NEUROBIOLOGY OFAMUSIA Congenital amusia can be conceived of as a neurodevelopmental disorder with presumed genetic origins.
A family aggregation study found an incidence of 39% in first degree relatives of probands, compared to only 3% of controls’ relatives (Peretz et al., 2007). A small number of structural imaging studies have revealed anomalies in superior temporal cortex and inferior frontal cortex of the right (Hyde et al., 2006; Hyde et al., 2007) or left (Mandell et al., 2007) hemispheres. In particular, Hyde et al. (2007) noted areas of cortical thickness in inferior frontal gyrus, which led them to suggest that congenital amusia may be characterized by abnormal neuronal migration between temporal and frontal areas. Loui et al. (2009) provided evidence to support this view, with a diffusion tensor imaging study that assessed the structural integrity of white matter tracts, in particular the arcuate fasciculus (AF) that traverses frontotemporal regions. They found that amusics had sparser AF tracts compared with controls, with the right superior tract unidentifiable in 9/10 participants. These results suggest a degree of disconnection along the fronto-temporal pathway in amusics and make the tentative prediction that any gene or sets of genes associated with the disorder may be involved in the early neural migration of neurons along this pathway (Stewart, 2008). Histological evidence shows that malformations in cortical development are also found in dyslexia (Galaburda et al., 2006) thus one possibility may be that both disorders result from aberrant neuronal migration and the differences in their behavioral manifestation relate to the particular pathways affected.
DEVELOPMENTAL TRAJECTORY All the studies reported so far have investigated congenital amusia in adults; however, the term “congenital” suggests the condition is present at birth and anecdotal reports support the notion that amusics’ difficulties with music perception and production may be present from early childhood. Mapping the clinical profile of congenital amusia in childhood would contribute to theories regarding the role of neural development in the expression of the disorder in adults and may also help to determine whether early intervention could lead to a degree of remediation. Systematic investigation of the developmental trajectory of the disorder will require the development of new diagnostic tools, since the MBEA is not currently suitable for use with children; recent studies have begun to address this issue (Lebrun et al., 2012). The employment of psycho-acoustic measures that are able to minimize age-related attentional and motivation factors would be particularly important in this regard.
CONCLUSIONS Congenital amusia is a neurodevelopmental disorder that leads to lifelong difficulties with perception and production of musical sounds. Studying congenital
CONGENITAL AMUSIA amusia gives us a unique window onto the multitude of cognitive skills that come together to allow engagement with music and demonstrates how musical behaviors relate to other complex human abilities, such as spoken language and spatial representation. Future work will determine not only the implications of the condition for individuals with congenital amusia but also allow us to better understand how genes, neural development, and behavior interact to produce an understanding and appreciation of our musical environment.
REFERENCES Allen G (1878). Note-deafness. Mind 10: 157–167. Ayotte J, Peretz I, Hyde K (2002). Congenital amusia: a group study of adults afflicted with a music-specific disorder. Brain 125: 238–251. Cuddy LL, Balkwill LL, Peretz I et al. (2005). Musical difficulties are rare: a study of ‘tone deafness’ among university students. In: G Avanzini, L Lopez, S Koelsch et al. (Eds.), The Neurosciences and Music II: From Perception to Performance. New York Academy of Sciences, New York, NY. Dalla Bella S, Gigue`re J-F, Peretz I (2009). Singing in congenital amusia. J Acoust Soc Am 126: 414–424. Douglas KM, Bilkey DK (2007). Amusia is associated with deficits in spatial processing. Nat Neurosci 10: 915–921. Dowling WJ (1978). Scale and contour: two components of a theory of memory for melodies. Psychol Rev 85: 341–354. Edworthy J (1985). Interval and contour in melody processing. Music Perc 2: 375–388. Foxton JM, Dean JL, Gee R et al. (2004). Characterization of deficits in pitch perception underlying “tone deafness”. Brain 127: 801–810. Galaburda AM, LoTurco J, Ramus F et al. (2006). From genes to behaviour in developmental dyslexia. Nat Neurosci 9: 1213–1217. Huron D (2006). Sweet Anticipation: Music and the Psychology of Expectation. The MIT Press, Cambridge. Hyde KL, Peretz I (2004). Brains that are out of tune but in time. Psychol Sci 15: 356–360. Hyde KL, Zatorre RJ, Griffiths TD et al. (2006). Morphometry of the amusic brain: a two-site study. Brain 129: 2562–2570. Hyde KL, Lerch JP, Zatorre RJ et al. (2007). Cortical thickness in congenital amusia: when less is better than more. J Neurosci 27: 13028–13032. Kalmus H, Fry DB (1980). On tune deafness (dysmelodia) – frequency, development, genetics and musical background. Ann Hum Genet 43: 369–382.
239
Lebrun MA, Moreau P, McNally-Gagnon A et al. (2012). Congenital amusia in childhood: a case study. Cortex in press. Liu F, Patel AD, Fourcin A et al. (2010). Intonation processing in congenital amusia: Discrimination, identification and imitation. Brain 133: 1682–1692. Loui P, Alsop D, Schlaug G (2009). Tone deafness: a new disconnection syndrome? J Neurosci 29: 10215–10220. Mandell J, Schulze K, Schlaug G (2007). Congenital amusia: an auditory-motor feedback disorder? Restor Neurol Neurosci 25: 323–334. McDonald C, Stewart L (2008). Uses and functions of music in congenital amusia. Music Perception 25: 345–355. Meyer LB (1956). Emotion and Meaning in Music. University of Chicago Press, Chicago. Patel AD, Foxton JM, Griffiths TD (2005). Musically tone-deaf individuals have difficulty discriminating intonation contours extracted from speech. Brain Cogn 59: 310–313. Peretz I, Champod AS, Hyde K et al. (2003). Varieties of musical disorders. The Montreal Battery of Evaluation of Amusia. In: G Avanzini, C Faienza, D Minciacchi et al. (Eds.), The Neurosciences and Music. New York Academy of Sciences, New York. Peretz I, Cummings S, Dube´ M-P (2007). The genetics of congenital amusia (Tone Deafness): A family-aggregation study. Am J Hum Genet 81: 582–588. Shepard R, Metzler J (1971). Mental rotation of three dimensional objects. Science 171: 701–703. Stewart L (2008). Fractionating the musical mind: insights from congenital amusia. Curr Opin Neurobiol 18: 127–130. Stewart L, Walsh V (2007). Music perception: sounds lost in space. Curr Biol 17: R892–R893. Tillmann B, Schulze K, Foxton JM (2009). Congenital amusia: a short-term memory deficit for nonverbal, but not verbal sounds. Brain Cogn 71: 259–264. Tillmann B, Jolicoeur P, Ishihara M et al. (2010). The amusic brain: lost in music, but not in space. Plos One 5: e10173. Williamson VJ, Stewart L (2010). Memory for pitch in congenital amusia: beyond a fine-grained pitch deficit. Memory 18: 657–669. Williamson VJ, Cocchini G, Stewart L (2011). The relationship between pitch and space in congenital amusia. Brain Cogn 76: 70–76. Williamson VJ, Liu F, Peryer G et al. (2012). Perception and action de-coupling in congenital amusia: sensitivity to task demands. Neuropsychologia 50: 172–180. Wise KJ, Sloboda JA (2008). Establishing an empirical profile of self-defined “tone deafness”: perception, singing performance and self-assessment. Musicae Scientiae 12: 3–26.