Browsing by Subject "musiikkiharrastus"

There are relatively few studies on pre-attentive auditory processing in middle-aged people. However, previous studies have shown that aging affects the ability to detect changes in regular auditory input at pre-attentive level as well as to involuntary allocation of attention. Recording of event-related brain potentials (ERPs) provides a good way for examining these phenomena. One purpose of this study was to find out whether musical expertise effects pre-attentive auditory processing in this particular age group. Results of many experiments have shown that children and young adults with musical expertise are more sensitive to acoustic properties of musical and phonemic sounds. There is also some evidence that adult musicians detect deviant pure tones more accurately than non-musicians. Based on this, we hypothesized that musicians would discriminate deviant tones in this study more accurately as well. Second aim of this study was to find out whether multi-feature paradigm can be used to examine pre-attentive auditory processing in middle-aged participants. In previous studies with young adults the multi-feature paradigm has proven to be a suitable way to study short-term memory and attention allocation. The 24 participants were derived into two groups based on their level of musical expertise. Participants in music group practiced music regularly and participants in non-music group had some other free time activities. We used a multi-feature paradigm that consisted of pure tone sound sequence in which four types of acoustic changes (frequency, duration, intensity and perceived sound-source location) varied in every other tone in three deviation magnitude (small, medium and large). Based on previous studies we assumed that these deviant tones would elicit both mismatch negativity (MMN) and P3a components, which are thought to reflect automatic, pre-attentive auditory processing. The magnitude of deviation was presumed to reflect in MMN and P3a amplitudes. In this study, no between-group differences were found for MMN or P3a amplitudes. However, MMN distributions slightly differed both frontally and laterally in these two groups. This finding might indicate that musical expertise has an influence on which parts of the brain auditory input is processed. As expected, deviant tones of small, medium and large magnitude elicited MMN components and medium and large deviations elicited also P3a components. As a rule, the amplitude of components increased with the magnitude of deviance. These results are in line with previous studies and show that the multi-feature paradigm can be used to examine pre-attentive auditory processing in middle-aged as in younger adults.

The aim of this study was to investigate using event-related potentials (ERP) whether musical training in childhood could have an effect on neural encoding of musical chords in the brainstem. Previous studies have found that musically trained individuals differ from non-musicians in various auditory skills, for example in discrimination of sounds. Much of the previous research has been conducted by comparing cortical ERPs between musicians and non-musicians. However, extensive neural encoding of sound properties happens at the subcortical level. For example, the neural representation of pitch and timbre are thought to be extracted in the lower part of auditory pathway, more precisely in brainstem nuclei. The auditory processing in brainstem shows experience-dependent plasticity. Auditory training in the laboratory has been shown to improve neural encoding of sounds at the brainstem level, and musical training has been linked to enhanced brainstem encoding of sounds. Sixty-two children, aged 11–17 years, participated in this study. The participants consisted of 35 musically trained (Music group) and 27 non-trained children (Control group). The children in the Music group attended an elementary school which is specialized in music; at school they had both solo instrument and orchestra practice as well as music theory lessons. The control children did not have any musical hobbies and they attended a regular elementary school. The Music and the Control groups were further divided into two age groups: younger (11–13 years) and older group (15–17 years). During the electroencephalography (EEG) recording session G major triad chords were presented to the subjects through headphones while they were instructed to concentrate on a silent movie. Frequency following responses (FFRs) were then extracted from the EEG data. FFRs are ERP responses which are thought to reflect phase-locked neural activity in the brainstem nuclei. Importantly, the temporal and spectral characteristics of the eliciting sounds are preserved in the response. We found that musically trained 15–17 -year old children showed enhanced spectral amplitudes for the second harmonic of the chord compared to the control children. This indicates that the neural encoding of the second harmonic was more accurate in musically trained children than in control children. In the younger group (11–13 year-olds) the spectral amplitudes for the chord harmonics did not differ between the Music and the Control group. The results suggest that musical training in childhood might improve the neural encoding of sound harmonics. To make a conclusion about a causal relationship between musical training and heightened neural encoding of sounds, a longitudinal research design will be needed in the future.