Memory structures for encoding and retrieving a piece of music: an ERP investigation

Musical Training and Brain Volume in Older Adults

Musical practice, including musical training and musical performance, has been found to benefit cognitive function in older adults. Less is known about the role of musical experiences on brain structure in older adults. The present study examined the role of different types of musical behaviors on brain structure in older adults. We administered the Goldsmiths Musical Sophistication Index, a questionnaire that includes questions about a variety of musical behaviors, including performance on an instrument, musical practice, allocation of time to music, musical listening expertise, and emotional responses to music. We demonstrated that musical training, defined as the extent of musical training, musical practice, and musicianship, was positively and significantly associated with the volume of the inferior frontal cortex and parahippocampus. In addition, musical training was positively associated with volume of the posterior cingulate cortex, insula, and medial orbitofrontal cortex. Together, the present study suggests that musical behaviors relate to a circuit of brain regions involved in executive function, memory, language, and emotion. As gray matter often declines with age, our study has promising implications for the positive role of musical practice on aging brain health.

Music, Language, and The N400: ERP Interference Patterns Across Cognitive Domains

Studies of the relationship of language and music have suggested these two systems may share processing resources involved in the computation/maintenance of abstract hierarchical structure (syntax). One type of evidence comes from ERP interference studies involving concurrent language/music processing showing interaction effects when both processing streams are simultaneously perturbed by violations (e.g., syntactically incorrect words paired with incongruent completion of a chord progression). Here, we employ this interference methodology to target the mechanisms supporting long term memory (LTM) access/retrieval in language and music. We used melody stimuli from previous work showing out-of-key or unexpected notes may elicit a musical analogue of language N400 effects, but only for familiar melodies, and not for unfamiliar ones. Target notes in these melodies were time-locked to visually presented target words in sentence contexts manipulating lexical/conceptual semantic congruity. Our study succeeded in eliciting expected N400 responses from each cognitive domain independently. Among several new findings we argue to be of interest, these data demonstrate that: (i) language N400 effects are delayed in onset by concurrent music processing only when melodies are familiar, and (ii) double violations with familiar melodies (but not with unfamiliar ones) yield a sub-additive N400 response. In addition: (iii) early negativities (RAN effects), which previous work has connected to musical syntax, along with the music N400, were together delayed in onset for familiar melodies relative to the timing of these effects reported in the previous music-only study using these same stimuli, and (iv) double violation cases involving unfamiliar/novel melodies also delayed the RAN effect onset. These patterns constitute the first demonstration of N400 interference effects across these domains and together contribute previously undocumented types of interactions to the available pool of findings relevant to understanding whether language and music may rely on shared underlying mechanisms.

Neural Evidence of Superior Memory: How to Capture Brain Activities of Encoding Processes Underlying Superior Memory

Relatively little attention has been paid to the neural basis of superior memory despite its potential in providing important insight into efforts to improve memory in the general population or to offset age-related cognitive decline. The current study reports a rare opportunity to reproduce and isolate specific neural activities directly associated with exceptional memory. To capture the brain processes responsible for superior memory, we returned to a laboratory task and analytic approach used to explore the nature of exceptional memory, namely, digit-span task combined with verbal protocol analysis. One participant with average memory received approximately 50 h of digit-span training and the participant's digit-span increased from normative (8 digits) to exceptional (30 digits). Event-related potentials were recorded while the participant's digit span increased from 19 to 30 digits. Protocol analysis allowed us to identify direct behavioral indices of idiosyncratic encoding processes underlying the superior memory performance. EEG indices directly corresponding to the behavioral indices of encoding processes were identified. The results suggest that the early attention-related encoding processes were reflected in theta and delta whereas the later attention-independent encoding processes were reflected in time-domain slow-wave. This fine-grained approach offers new insights into studying neural mechanism mediating superior memory and the cognitive effort necessary to develop it.

Cross-modal music integration in expert memory: Evidence from eye movements

The study investigated the cross-modal integration hypothesis for expert musicians using eye tracking. Twenty randomized excerpts of classical music were presented in two modes (auditory and visual), at the same time (simultaneously) or successively (sequentially). Musicians (N = 53, 26 experts and 27 non-experts) were asked to detect a note modified between the auditory and visual versions, either in the same major/minor key or violating the key. Experts carried out the task faster and with greater accuracy than non-experts. Sequential presentation was more difficult than simultaneous (longer fixations and higher error rates) and the modified notes were more easily detected when violating the key (fewer errors), but with longer fixations (speed/accuracy trade-off strategy). Experts detected the modified note faster, especially in the simultaneous condition in which cross-modal integration may be applied. These results support the hypothesis that the main difference between experts and non-experts derives from the difference in knowledge structures in memory built over time with practice. They also suggest that these high-level knowledge structures in memory contain harmony and tonal rules, arguing in favour of cross-modal integration capacities for experts, which are related to and can be explained by the long-term working memory (LTWM) model of expert memory (e.g. (18; 22).

Why Is Working Memory Performance Unstable? A Review of 21 Factors

In this paper, we systematically reviewed twenty-one factors that have been shown to either vary with or influence performance on working memory (WM) tasks. Specifically, we review previous work on the influence of intelligence, gender, age, personality, mental illnesses/medical conditions, dieting, craving, stress/anxiety, emotion/motivation, stereotype threat, temperature, mindfulness training, practice, bilingualism, musical training, altitude/hypoxia, sleep, exercise, diet, psychoactive substances, and brain stimulation on WM performance. In addition to a review of the literature, we suggest several frameworks for classifying these factors, identify shared mechanisms between several variables, and suggest areas requiring further investigation. This review critically examines the breadth of research investigating WM while synthesizing the results across related subfields in psychology.

Music training and working memory: an ERP study

While previous research has suggested that music training is associated with improvements in various cognitive and linguistic skills, the mechanisms mediating or underlying these associations are mostly unknown. Here, we addressed the hypothesis that previous music training is related to improved working memory. Using event-related potentials (ERPs) and a standardized test of working memory, we investigated both neural and behavioral aspects of working memory in college-aged, non-professional musicians and non-musicians. Behaviorally, musicians outperformed non-musicians on standardized subtests of visual, phonological, and executive memory. ERPs were recorded in standard auditory and visual oddball paradigms (participants responded to infrequent deviant stimuli embedded in lists of standard stimuli). Electrophysiologically, musicians demonstrated faster updating of working memory (shorter latency P300s) in both the auditory and visual domains and musicians allocated more neural resources to auditory stimuli (larger amplitude P300), showing increased sensitivity to the auditory standard/deviant difference and less effortful updating of auditory working memory. These findings demonstrate that long-term music training is related to improvements in working memory, in both the auditory and visual domains and in terms of both behavioral and ERP measures.

Musicians' and nonmusicians' short-term memory for verbal and musical sequences: comparing phonological similarity and pitch proximity

Language-music comparative studies have highlighted the potential for shared resources or neural overlap in auditory short-term memory. However, there is a lack of behavioral methodologies for comparing verbal and musical serial recall. We developed a visual grid response that allowed both musicians and nonmusicians to perform serial recall of letter and tone sequences. The new method was used to compare the phonological similarity effect with the impact of an operationalized musical equivalent-pitch proximity. Over the course of three experiments, we found that short-term memory for tones had several similarities to verbal memory, including limited capacity and a significant effect of pitch proximity in nonmusicians. Despite being vulnerable to phonological similarity when recalling letters, however, musicians showed no effect of pitch proximity, a result that we suggest might reflect strategy differences. Overall, the findings support a limited degree of correspondence in the way that verbal and musical sounds are processed in auditory short-term memory.

Match and Mismatch of Taste, Odor, and Color is Reflected by Electrical Activity in the Human Brain

We aimed at elucidating the relationship between odor, taste, color, and food stimuli where subjects were studied either with questionnaires or in electrophysiological experiments. First, a total of 144 word pairs were rated by 660 subjects who determined whether the first stimulus (odor or taste word) matched the second one (color or food word). In an electrophysiological experiment, EEG was recorded from 30 electrodes in 24 healthy adults while clearly matching, or nonmatching, word pairs were presented on a monitor. Evoked potentials were computed for different stimulus classes (matching or nonmatching combinations of odor or taste and color or food words). Six components were identified and compared between conditions. For most components, field strength (GFP) was lower for nonmatching than for matching word pairs. In addition to late effects, electrical brain activity was influenced by experimental conditions as early as at 100 ms latency. Most effects observed were in the time range between 100 and 250 ms. Our data show how color and food words are differently affected when paired with odor or taste words. Complex interactions between stimulus modality (taste/odor) and different target words (color/food) occurred depending on whether the pairs were seen by the subjects as appropriate or inappropriate. Topographical effects indicated that different neural populations were activated in different conditions. Most interestingly, there were many cognitive effects occurring quite early (on the order of 100 ms) after stimulus presentation, and our results suggest rapid cognitive processing of information on odor, taste, color, and food items. This is an important prerequisite for the preconscious and fast choice of food items in everyday behavior, and the data confirm earlier findings on rapid and preconscious semantic processing in the visual cortex.

Does music enhance cognitive performance in healthy older adults? The Vivaldi effect

BACKGROUND AND AIMS

Controversial evidence suggests that music can enhance cognitive performance. In the present study, we examined whether listening to an excerpt of Vivaldi's "Four Seasons" had a positive effect on older adults' cognitive performance in two working memory tasks.

METHODS

With a repeated-measures design, older adults were presented with the forward version of the digit span and phonemic fluency in classical music, white-noise and no-music conditions.

RESULTS

Classical music significantly increased working memory performance compared with the no-music condition. In addition, this effect did not occur with white noise.

CONCLUSION

The authors discuss this finding in terms of the arousal-and-mood hypothesis and the role of working memory resources in aging.