Absolute pitch, the ability to name or produce a musical tone without a reference, is a rare ability which is often related to early musical training and genetic components. However, it remains a matter of debate why absolute pitch is relatively common in autism spectrum disorders and why absolute pitch possessors exhibit higher autistic traits. By definition absolute pitch is an ability that does not require the relation of tones but is based on a lower-level perceptual entity than relative pitch (involving relations between tones, intervals, and melodies). This study investigated whether a detail-oriented cognitive style, a concept borrowed from the autism literature (weak central coherence theory), might provide a framework to explain this joint occurrence. Two local-to-global experiments in vision (hierarchically constructed letters) and audition (hierarchically constructed melodies) as well as a pitch adjustment test measuring absolute pitch proficiency were conducted in 31 absolute pitch and 33 relative pitch professional musicians. Analyses revealed inconsistent group differences among reaction time, total of correct trials and speed-accuracy-composite-scores of experimental conditions (local vs. global, and congruent vs. incongruent stimuli). Furthermore, amounts of interference of global form on judgments of local elements and vice versa were calculated. Interestingly, reduced global-to-local interference in audition was associated with greater absolute pitch ability and in vision with higher autistic traits. Results are partially in line with the idea of a detail-oriented cognitive style in absolute pitch musicians. The inconsistency of the results might be due to limitations of global-to-local paradigms in measuring cognitive style and due to heterogeneity of absolute pitch possessors. In summary, this study provides further evidence for a multifaceted pattern of various and potentially interacting factors on the acquisition of absolute pitch.

Background Recent studies indicate increased autistic traits in musicians with absolute pitch and a higher proportion of absolute pitch in people with autism. Theoretical accounts connect both of these with shared neural principles of local hyper- and global hypoconnectivity, enhanced perceptual functioning, and a detail-focused cognitive style. This is the first study to investigate absolute pitch proficiency, autistic traits, and brain correlates in the same study. Sample and methods Graph theoretical analysis was conducted on resting-state (eyes closed and eyes open) EEG connectivity (wPLI, weighted phase lag index) matrices obtained from 31 absolute pitch (AP) and 33 relative pitch (RP) professional musicians. Small-worldness, global clustering coefficient, and average path length were related to autistic traits, passive (tone identification) and active (pitch adjustment) absolute pitch proficiency, and onset of musical training using Welch two-sample tests, correlations, and general linear models. Results Analyses revealed increased path length (delta 2–4 Hz), reduced clustering (beta 13–18 Hz), reduced small-worldness (gamma 30–60 Hz), and increased autistic traits for AP compared to RP. Only clustering values (beta 13–18 Hz) were predicted by both AP proficiency and autistic traits. Post hoc single connection permutation tests among raw wPLI matrices in the beta band (13–18 Hz) revealed widely reduced interhemispheric connectivity between bilateral auditory-related electrode positions along with higher connectivity between F7–F8 and F8–P9 for AP. Pitch-naming ability and pitch adjustment ability were predicted by path length, clustering, autistic traits, and onset of musical training (for pitch adjustment) explaining 44% and 38% of variance, respectively. Conclusions Results show both shared and distinct neural features between AP and autistic traits. Differences in the beta range were associated with higher autistic traits in the same population. In general, AP musicians exhibit a widely underconnected brain with reduced functional integration and reduced small-world property during resting state. This might be partly related to autism-specific brain connectivity, while differences in path length and small-worldness reflect other ability-specific influences. This is further evidenced for different pathways in the acquisition and development of absolute pitch, likely influenced by both genetic and environmental factors and their interaction.

Absolute pitch (AP) and autism have recently been associated with each other. Neurocognitive theories of autism could perhaps explain this co-occurrence. This study investigates whether AP musicians show an advantage in an interleaved melody recognition task (IMRT), an auditory version of an embedded figures test often investigated in autism with respect to the these theories. A total of N = 59 professional musicians (AP = 27) participated in the study. In each trial a probe melody was followed by an interleaved sequence. Participants had to indicate as to whether the probe melody was present in the interleaved sequence. Sensitivity index d′ and response bias c were calculated according to signal detection theory. Additionally, a pitch adjustment test measuring fine-graded differences in absolute pitch proficiency, the Autism-Spectrum-Quotient and a visual embedded figures test were conducted. AP outperformed relative pitch (RP) possessors on the overall IMRT and the fully interleaved condition. AP proficiency, visual disembedding and musicality predicted 39.2% of variance in the IMRT. No correlations were found between IMRT and autistic traits. Results are in line with a detailed-oriented cognitive style and enhanced perceptional functioning of AP musicians similar to that observed in autism.

1 Background 2Recent studies indicate increased autistic traits in musicians with absolute pitch and a higher 3 incidence of absolute pitch in people with autism. Theoretical accounts connect both of these with 4 shared neural principles of local hyper-and global hypoconnectivity, enhanced perceptual 5 functioning and a detail-focused cognitive style. This is the first study to investigate absolute pitch 6 proficiency, autistic traits and brain correlates in the same study. 7 Sample and Methods 8Graph theoretical analysis was conducted on resting state (eyes closed and eyes open) EEG 9 connectivity (wPLI, weighted Phase Lag Index) matrices obtained from 31 absolute pitch (AP) and 10 33 relative pitch (RP) professional musicians. Small Worldness, Global Clustering Coefficient and 11Average Path length were related to autistic traits, passive (tone identification) and active (pitch 12 adjustment) absolute pitch proficiency and onset of musical training using Welch-two-sample-tests, 13 correlations and general linear models. 14 Results 15Analyses revealed increased Path length (delta 2-4 Hz), reduced Clustering (beta 13-18 Hz), 16reduced Small-Worldness (gamma 30-60 Hz) and increased autistic traits for AP compared to RP. 17 Only Clustering values (beta 13-18 Hz) were predicted by both AP proficiency and autistic traits. 18Post-hoc single connection permutation tests among raw wPLI matrices in the beta band (13-18 Hz) 19 revealed widely reduced interhemispheric connectivity between bilateral auditory related electrode 20 positions along with higher connectivity between F7-F8 and F8-P9 for AP. Pitch naming ability and 21Pitch adjustment ability were predicted by Path length, Clustering, autistic traits and onset of 22 musical training (for pitch adjustment) explaining 44% respectively 38% of variance. 23 Conclusions 24Results show both shared and distinct neural features between AP and autistic traits. Differences in 25 the beta range were associated with higher autistic traits in the same population. In general, AP 26 3 musicians exhibit a widely underconnected brain with reduced functional integration and reduced 27 small-world-property during resting state. This might be partly related to autism-specific brain 28 connectivity, while differences in Path length and Small-Worldness reflect other ability-specific 29 influences. This is further evidence for different pathways in the acquisition and development of 30 absolute pitch, likely influenced by both genetic and environmental factors and their interaction. 31 32 Keywords: 33 absolute pitch, autistic traits, brain networks, graph theory, musicians, electroencephalography 34 35 Background 36 37 Autism spectrum disorders or conditions (henceforth 'autism') are more common in people with 38 mathematical [1], visuo-spatial [2], musical [3] or 'savant' abilities [4], e.g. rapid mental 39 mathematical calculation [5, 6], calendar calculation [7], or extreme memory [8, 9]. Autism, a set of 40 neurodevelopmental condition, are characterized by social and communicatio...

4Autistic people exhibit enhanced abilities to find and extract visual or auditory figures out of 5 a meaningful whole (disembedding). Studies have shown heightened autistic traits in 6 professional musicians with absolute pitch (AP). This study investigates whether such 7 musicians show an advantage in an interleaved melody recognition task (IMRT). 8A total of N=59 professional musicians (AP=27) participated in the study. In each trial a 9 probe melody was followed by an interleaved sequence. Subjects had to indicate as to 10whether the probe melody was present in the interleaved sequence. Sensitivity index d´ 11and response bias c were calculated according to signal detection theory. Additionally, a 12pitch adjustment test measuring fine-graded differences in absolute pitch proficiency, the 13Autism-Spectrum-Quotient and a visual embedded figures test were conducted. 14 AP performance was enhanced overall compared to RP. Absolute pitch proficiency, visual 15 disembedding ability and musicality predicted approximately 39.2% of variance in the 16interleaved melody recognition test. No correlations were found between IMRT and autistic 17traits. 18The stable pitch-label associations of AP might serve as additional sensory cues during 19pre-attentive processing in recognizing interleaved melodies. Results are in line with a 20detailed-oriented cognitive style and enhanced perceptional functioning of AP musicians 21 similar to that observed in autism. 22 23