Monthly Archives: June 2011
Performing music is a multimodal experience involving the visual, auditory, and somatosensory modalities as well as the motor system. Therefore, musical training is an excellent model to study multimodal brain plasticity. Indeed, we have previously shown that short-term piano practice increase the magnetoencephalographic (MEG) response to melodic material in novice players. Here we investigate the impact of piano training using a rhythmic-focused exercise on responses to rhythmic musical material. Musical training with non musicians was conducted over a period of two weeks. One group (sensorimotor-auditory, SA) learned to play a piano sequence with a distinct musical rhythm, another group (auditory, A) listened to, and evaluated the rhythmic accuracy of the performances of the SA-group. Training-induced cortical plasticity was evaluated using MEG, comparing the mismatch negativity (MMN) in response to occasional rhythmic deviants in a repeating rhythm pattern before and after training. The SA-group showed a significantly greater enlargement of MMN and P2 to deviants after training compared to the A- group. The training-induced increase of the rhythm MMN was bilaterally expressed in contrast to our previous finding where the MMN for deviants in the pitch domain showed a larger right than left increase. The results indicate that when auditory experience is strictly controlled during training, involvement of the sensorimotor system and perhaps increased attentional recources that are needed in producing rhythms lead to more robust plastic changes in the auditory cortex compared to when rhythms are simply attended to in the auditory domain in the absence of motor production.
from PLoS ONE
Maternal smoking during pregnancy had a negative effect on cochlear function, as determined by otoacoustic emissions testing. Therefore, pregnant women should be warned of this additional hazard of smoking. It is important that smoking control be viewed as a public health priority and that strategies for treating tobacco dependence be devised.
Prognostic validity of dichotic multiple frequencies auditory steady-state responses versus distortion product otoacoustic emissions in hearing screening of high risk neonates
ASSR with this special paradigm is a fairly desirable method for hearing screening of high-risk neonates. There is good concordance between ASSRs and DOPAEs results among high risk neonates referred for hearing screening. The sensitivity and specificity of this test is sufficient for hearing screening in high risk neonates. This test could be valuable for rapid confirmation of normal thresholds. As long as further research have not been conducted on ASSR, great caution should be made to interpret the results of ASSR as a hearing screening technique in young infants and also additional techniques such as the tone-evoked ABRs should be used to cross-check results. It’s still too soon to recommend ASSRs as a standalone electrophysiologic measure of hearing thresholds in infants.
Speech perception in noise deficits in Japanese children with reading difficulties: Effects of presentation rate
We examined the effects of presentation rate on speech perception in noise and its relation to reading in 117 typically developing (TD) children and 10 children with reading difficulties (RD) in Japan. Responses in a speech perception task were measured for speed, accuracy, and stability in two conditions that varied stimulus presentation rate: high rate and same rate conditions. TD children exhibited significantly more stable responses in the high rate condition than they did in the same rate condition. Multiple regression analyses indicated that response stability in the high rate condition accounted for a unique amount of variance in reading and mora deletion. As a group, children with RD performed less accurately than did TD children in the high rate condition, but not in the same rate condition. Findings suggest that the dependence of speech perception on stimulus context relates to reading proficiency or difficulty in Japanese children. The influences of phonology and orthography of language on the relationships between speech perception and reading are discussed.
Prediction of Reading Skill Several Years Later Depends on Age and Brain Region: Implications for Developmental Models of Reading
We investigated whether brain activity was predictive of future reading skill and, if so, how this brain–behavior correlation informs developmental models of reading. A longitudinal study followed 26 normally developing human children ranging in age from 9 to 15 years who were initially assessed for reading skill and performed a rhyming judgment task during functional magnetic resonance imaging. Patterns of brain activation in this task predicted changes between initial and a follow-up assessment of nonword reading skill administered up to 6 years later. Brain activity in areas typically active during imaging studies of reading was found to predict future nonword reading ability, but the predictive ability of these areas depended on age. Increased activity relative to peers in neural circuits associated with phonological recoding (i.e., inferior frontal gyrus and basal ganglia) was predictive of greater gains in reading fluency in younger children, whereas increased activity relative to peers in orthographic processing circuits (i.e., fusiform gyrus) was predictive of smaller gains in fluency for older children. Interpreted within the context of a connectionist model of reading, these results suggest that younger children who are more sensitive to higher-order phonological word characteristics (e.g., coarticulations) may make greater reading proficiency gains, whereas older children who focus more on whole-word orthographic representations may make smaller proficiency gains.
from the Journal of Neuroscience
In accordance with influential models proposing prioritized processing of threat, previous studies have shown automatic brain responses to angry prosody in the amygdala and the auditory cortex under auditory distraction conditions. However, it is unknown whether the automatic processing of angry prosody is also observed during cross-modal distraction. The current fMRI study investigated brain responses to angry versus neutral prosodic stimuli during visual distraction. During scanning, participants were exposed to angry or neutral prosodic stimuli while visual symbols were displayed simultaneously. By means of task requirements, participants either attended to the voices or to the visual stimuli. While the auditory task revealed pronounced activation in the auditory cortex and amygdala to angry versus neutral prosody, this effect was absent during the visual task. Thus, our results show a limitation of the automaticity of the activation of the amygdala and auditory cortex to angry prosody. The activation of these areas to threat-related voices depends on modality-specific attention.
from the Journal of Neuroscience
What makes us laugh? One crucial component of many jokes is the disambiguation of words with multiple meanings. In this functional MRI study of normal participants, the neural mechanisms that underlie our experience of getting a joke that depends on the resolution of semantically ambiguous words were explored. Jokes that contained ambiguous words were compared with sentences that contained ambiguous words but were not funny, as well as to matched verbal jokes that did not depend on semantic ambiguity. The results confirm that both the left inferior temporal gyrus and left inferior frontal gyrus are involved in processing the semantic aspects of language comprehension, while a more widespread network that includes both of these regions and the temporoparietal junction bilaterally is involved in processing humorous verbal jokes when compared with matched nonhumorous material. In addition, hearing jokes was associated with increased activity in a network of subcortical regions, including the amygdala, the ventral striatum, and the midbrain, that have been implicated in experiencing positive reward. Moreover, activity in these regions correlated with the subjective ratings of funniness of the presented material. These results allow a more precise account of how the neural and cognitive processes that are involved in ambiguity resolution contribute to the appreciation of jokes that depend on semantic ambiguity.
from the Journal of Neuroscience
Functional magnetic resonance imaging exploration of combined hand and speech movements in Parkinson’s disease
Among the repertoire of motor functions, although hand movement and speech production tasks have been investigated widely by functional neuroimaging, paradigms combining both movements have been studied less so. Such paradigms are of particular interest in Parkinson’s disease, in which patients have specific difficulties performing two movements simultaneously. In 9 unmedicated patients with Parkinson’s disease and 15 healthy control subjects, externally cued tasks (i.e., hand movement, speech production, and combined hand movement and speech production) were performed twice in a random order and functional magnetic resonance imaging detected cerebral activations, compared to the rest. F-statistics tested within-group (significant activations at P values < 0.05, familywise error corrected), between-group, and between-task comparisons (regional activations significant at P values 10 voxels). For control subjects, the combined task activations comprised the sum of those obtained during hand movement and speech production performed separately, reflecting the neural correlates of performing movements sharing similar programming modalities. In patients with Parkinson’s disease, only activations underlying hand movement were observed during the combined task. We interpreted this phenomenon as patients’ potential inability to recruit facilitatory activations while performing two movements simultaneously. This lost capacity could be related to a functional prioritization of one movement (i.e., hand movement), in comparison with the other (i.e., speech production). Our observation could also reflect the inability of patients with Parkinson’s disease to intrinsically engage the motor coordination necessary to perform a combined task. © 2011 Movement Disorder Society
from Movement Disorders
Attention problems and language development in preterm low-birth-weight children: Cross-lagged relations from 18 to 36 months.
Preliminary evidence was found for a precursor role of early attention problems in relation to language in prematurity. This finding can contribute to a better understanding of the developmental pathways of attention and language and lead to better management of unfavourable outcomes associated with co-morbid attention and language difficulties.
from BMC Pediatrics
This paper examines the links between language use, speakers and institutional authority at the oldest Aymara-language radio station in Bolivia. The station’s Aymara language department develops and approves scripts and monitors programming, identifying Spanish loan words – “aberrations” – and replacing them with Aymara neologisms. In the context of indigenous political resurgence in Bolivia, language has become a metonym for the indigenous nation, another terrain for decolonization and personal transformation. Drawing on ethnographic fieldwork and discourse analysis of a broadcast of the program Aymara Language, I argue that the metadiscursive regime operating at the station plays a role in consolidating a distinct register of Aymara and its elusive model speaker.
Tinnitus is an auditory phantom percept with a tone, hissing, or buzzing sound in the absence of any objective physical sound source. Persons with tinnitus engage in a number of health behaviors to manage tinnitus. This can go from prescription medication, masking devices, behavioral training techniques to cortical implants. Potentially less adaptive methods of coping with tinnitus, such as the use of alcohol, are poorly studied. The purpose of this study was to further explore the neurobiological mechanism of tinnitus improvement by the use of alcohol. We observed differences in the alpha, beta and gamma frequency band when comparing resting-state EEG before and after alcohol intake. More precisely increased synchronized alpha1 activity was found in the posterior cingulate cortex and decreased synchronized alpha2 activity was demonstrated in orbitofrontal cortex, ventrolateral prefrontal cortex and subcallosal anterior cingulate cortex after alcohol intake. Increased synchronized activity was found in a region between the pregenual and dorsal anterior cingulate cortex and the left insula for beta and decreased activity in the precuneus after alcohol intake. For the gamma frequency band decreased synchronized activity in the precuneus and the posterior cingulate cortex was demonstrated after alcohol intake. Region of interest analyses in auditory cortices and parahippocampal area revealed however no differences in the different frequency bands before and after alcohol consumption.
from Brain Topography
We reported a 78-year-old woman who had a sudden-onset episode of vertigo, nausea and vomiting. Half an hour later, she felt right hemiataxia, and then noticed numbness on the entire right side of the face. She did not complain of hearing disorders or sensory disorders of left half body involving face. Pure tone audiogram and auditory brainstem responses were normal. Magnetic resonance imaging showed right hypersignals in the dorsolateral pons and middle cerebellar peduncle, as well as in cerebellum. Magnetic resonance angiography showed occlusion of the right anterior inferior cerebellar artery (AICA). Neuroradiological findings suggested ischemia in the whole territory of the right AICA. This is a case of AICA infarction and clinicians should be aware that sensory defect was only in the ipsilateral face without hearing disorders can be the manifestation of AICA infarction.
Volumes of Lateral Temporal and Parietal Structures Distinguish Between Healthy Aging, Mild Cognitive Impairment, and Alzheimer’s Disease
Distinguishing amnestic mild cognitive impairment (MCI) from Alzheimer’s disease (AD) and healthy aging depends mainly on clinical evaluation, and, ultimately, on investigator’s judgment. Clinical evaluation in vivo is based primarily on cognitive assessments. The present study explores the potential of volumetric magnetic resonance imaging of parietal and lateral temporal brain structures to support the diagnosis of AD and to distinguish AD patients from patients with MCI and healthy control subjects (HCS). 52 age-matched HCS, 18 patients with MCI, and 59 patients with probable late onset AD were investigated. Using computational, neuromorphometric procedures gray matter (GM) was automatically parcellated into 28 local regions of interest, the volumes of which were computed. The left hippocampus (sensitivity/specificity: 80.8–90.4%/55.6–86.4%) and the right hippocampus (73.1–90.4%/66.7–84.7%) provided highest diagnostic accuracy in separating all three diagnostic groups. Promising diagnostic values for distinguishing MCI from HCS were found for the left superior parietal gyrus (61.5%/55.6%) and left supramarginal gyrus (65.4%/66.7%), and for distinguishing subjects with MCI from AD patients for the right middle temporal gyrus (77.8%/79.7%), left inferior temporal gyrus (83.3%/72.9%), and right superior temporal gyrus (77.8%/71.2%). The left superior temporal pole (92.3%/84.7%), left parahippocampal gyrus (86.5%/81.4%), left Heschl’s gyrus (86.5%/79.7%), and the right superior temporal pole (82.7%/78.0%) revealed most promising diagnostic values for distinguishing AD patients from HCS. Data revealed that lateral temporal and parietal GM volumes distinguish between HCS, MCI, and AD as accurate as hippocampal volumes do; hence, these volumes can be used in the diagnostic procedure. Results also suggest that cognitive functions associated with these brain regions, e.g., language and visuospatial abilities, may be tested more extensively to obtain additional information that might enhance the diagnostic accuracy further.
from the Journal of Alzheimer’s Disease
How Many Functional Brains in Developmental Dyslexia? When the History of Language Delay Makes the Difference
Conclusions: Neurofunctional profiles of Italian individuals with DD are correlated to the history of language delay, suggesting that the relatively better behavioral profiles observed in individuals without a history of language delay are associated with a major activation of frontal networks normally involved in phonological working memory.