Repetitive transcranial magnetic stimulation over inferior frontal cortex impairs the suppression (but not expression) of action impulses during action conflict.

In the recent literature, the effects of noninvasive neurostimulation on cognitive functioning appear to lack consistency and replicability. We propose that such effects may be concealed unless dedicated, sensitive, and process-specific dependent measures are used. The expression and subsequent suppression of response capture are often studied using conflict tasks. Response-time distribution analyses have been argued to provide specific measures of the susceptibility to make fast impulsive response errors, as well as the proficiency of the selective suppression of these impulses. These measures of response capture and response inhibition are particularly sensitive to experimental manipulations and clinical deficiencies that are typically obfuscated in commonly used overall performance analyses. Recent work using structural and functional imaging techniques links these behavioral outcome measures to the integrity of frontostriatal networks. These studies suggest that the presupplementary motor area (pre-SMA) is linked to the susceptibility to response capture whereas the right inferior frontal cortex (rIFC) is associated with the selective suppression of action impulses. Here, we used repetitive transcranial magnetic stimulation (rTMS) to test the causal involvement of these two cortical areas in response capture and inhibition in the Simon task. Disruption of rIFC function specifically impaired selective suppression of conflicting action tendencies, whereas the anticipated increase of fast impulsive errors after perturbing pre-SMA function was not confirmed. These results provide a proof of principle of the notion that the selection of appropriate dependent measures is perhaps crucial to establish the effects of neurostimulation on specific cognitive functions.

Entrainment to an auditory signal: Is attention involved?

Many natural auditory signals, including music and language, change periodically. The effect of such auditory rhythms on the brain is unclear however. One widely held view, dynamic attending theory, proposes that the attentional system entrains to the rhythm and increases attention at moments of rhythmic salience. In support, 2 experiments reported here show reduced response times to visual letter strings shown at auditory rhythm peaks, compared with rhythm troughs. However, we argue that an account invoking the entrainment of general attention should further predict rhythm entrainment to also influence memory for visual stimuli. In 2 pseudoword memory experiments we find evidence against this prediction. Whether a pseudoword is shown during an auditory rhythm peak or not is irrelevant for its later recognition memory in silence. Other attention manipulations, dividing attention and focusing attention, did result in a memory effect. This raises doubts about the suggested attentional nature of rhythm entrainment. We interpret our findings as support for auditory rhythm perception being based on auditory-motor entrainment, not general attention entrainment. (PsycINFO Database Record

An Independent Psychometric Evaluation of the PROMS Measure of Music Perception Skills.

The Profile of Music Perception Skills (PROMS) is a recently developed measure of perceptual music skills which has been shown to have promising psychometric properties. In this paper we extend the evaluation of its brief version to three kinds of validity using an individual difference approach. The brief PROMS displays good discriminant validity with working memory, given that it does not correlate with backward digit span (r = .04). Moreover, it shows promising criterion validity (association with musical training (r = .45), musicianship status (r = .48), and self-rated musical talent (r = .51)). Finally, its convergent validity, i.e. relation to an unrelated measure of music perception skills, was assessed by correlating the brief PROMS to harmonic closure judgment accuracy. Two independent samples point to good convergent validity of the brief PROMS (r = .36; r = .40). The same association is still significant in one of the samples when including self-reported music skill in a partial correlation (rpartial = .30; rpartial = .17). Overall, the results show that the brief version of the PROMS displays a very good pattern of construct validity. Especially its tuning subtest stands out as a valuable part for music skill evaluations in Western samples. We conclude by briefly discussing the choice faced by music cognition researchers between different musical aptitude measures of which the brief PROMS is a well evaluated example.

Internal conceptual replications do not increase independent replication success.

Recently, many psychological effects have been surprisingly difficult to reproduce. This article asks why, and investigates whether conceptually replicating an effect in the original publication is related to the success of independent, direct replications. Two prominent accounts of low reproducibility make different predictions in this respect. One account suggests that psychological phenomena are dependent on unknown contexts that are not reproduced in independent replication attempts. By this account, internal replications indicate that a finding is more robust and, thus, that it is easier to independently replicate it. An alternative account suggests that researchers employ questionable research practices (QRPs), which increase false positive rates. By this account, the success of internal replications may just be the result of QRPs and, thus, internal replications are not predictive of independent replication success. The data of a large reproducibility project support the QRP account: replicating an effect in the original publication is not related to independent replication success. Additional analyses reveal that internally replicated and internally unreplicated effects are not very different in terms of variables associated with replication success. Moreover, social psychological effects in particular appear to lack any benefit from internal replications. Overall, these results indicate that, in this dataset at least, the influence of QRPs is at the heart of failures to replicate psychological findings, especially in social psychology. Variable, unknown contexts appear to play only a relatively minor role. I recommend practical solutions for how QRPs can be avoided.

Language influences music harmony perception: effects of shared syntactic integration resources beyond attention.

Many studies have revealed shared music-language processing resources by finding an influence of music harmony manipulations on concurrent language processing. However, the nature of the shared resources has remained ambiguous. They have been argued to be syntax specific and thus due to shared syntactic integration resources. An alternative view regards them as related to general attention and, thus, not specific to syntax. The present experiments evaluated these accounts by investigating the influence of language on music. Participants were asked to provide closure judgements on harmonic sequences in order to assess the appropriateness of sequence endings. At the same time participants read syntactic garden-path sentences. Closure judgements revealed a change in harmonic processing as the result of reading a syntactically challenging word. We found no influence of an arithmetic control manipulation (experiment 1) or semantic garden-path sentences (experiment 2). Our results provide behavioural evidence for a specific influence of linguistic syntax processing on musical harmony judgements. A closer look reveals that the shared resources appear to be needed to hold a harmonic key online in some form of syntactic working memory or unification workspace related to the integration of chords and words. Overall, our results support the syntax specificity of shared music-language processing resources.

Music and Language Syntax Interact in Broca's Area: An fMRI Study.

Instrumental music and language are both syntactic systems, employing complex, hierarchically-structured sequences built using implicit structural norms. This organization allows listeners to understand the role of individual words or tones in the context of an unfolding sentence or melody. Previous studies suggest that the brain mechanisms of syntactic processing may be partly shared between music and language. However, functional neuroimaging evidence for anatomical overlap of brain activity involved in linguistic and musical syntactic processing has been lacking. In the present study we used functional magnetic resonance imaging (fMRI) in conjunction with an interference paradigm based on sung sentences. We show that the processing demands of musical syntax (harmony) and language syntax interact in Broca's area in the left inferior frontal gyrus (without leading to music and language main effects). A language main effect in Broca's area only emerged in the complex music harmony condition, suggesting that (with our stimuli and tasks) a language effect only becomes visible under conditions of increased demands on shared neural resources. In contrast to previous studies, our design allows us to rule out that the observed neural interaction is due to: (1) general attention mechanisms, as a psychoacoustic auditory anomaly behaved unlike the harmonic manipulation, (2) error processing, as the language and the music stimuli contained no structural errors. The current results thus suggest that two different cognitive domains-music and language-might draw on the same high level syntactic integration resources in Broca's area.

Speed and accuracy of dyslexic versus typical word recognition: an eye-movement investigation.

Developmental dyslexia is often characterized by a dual deficit in both word recognition accuracy and general processing speed. While previous research into dyslexic word recognition may have suffered from speed-accuracy trade-off, the present study employed a novel eye-tracking task that is less prone to such confounds. Participants (10 dyslexics and 12 controls) were asked to look at real word stimuli, and to ignore simultaneously presented non-word stimuli, while their eye-movements were recorded. Improvements in word recognition accuracy over time were modeled in terms of a continuous non-linear function. The words' rhyme consistency and the non-words' lexicality (unpronounceable, pronounceable, pseudohomophone) were manipulated within-subjects. Speed-related measures derived from the model fits confirmed generally slower processing in dyslexics, and showed a rhyme consistency effect in both dyslexics and controls. In terms of overall error rate, dyslexics (but not controls) performed less accurately on rhyme-inconsistent words, suggesting a representational deficit for such words in dyslexics. Interestingly, neither group showed a pseudohomophone effect in speed or accuracy, which might call the task-independent pervasiveness of this effect into question. The present results illustrate the importance of distinguishing between speed- vs. accuracy-related effects for our understanding of dyslexic word recognition.