Scanning the stammering brain

2000 ◽  
Vol 17 (4) ◽  
pp. 140-142 ◽  
Author(s):  
Caoimhghín S Breathnach
Keyword(s):  
Public Speaking ◽  
Right Hemisphere ◽  
Word Reading ◽  
Motor Preparation ◽  
Single Word ◽  
Regional Cerebral Blood ◽  
Self Monitoring ◽  
Single Word Reading ◽  
The Right ◽  
Abnormal Motor

AbstractStammering (or stuttering) may be defined as an impairment of continuous utterance. Developmental stammering, regardless of country or language, affects one per cent of adult populations. Exacerbation by the stress of adult conversation or public speaking contrasts sharply with normal flow during singing, acting or conversation with children. Alterations in regional cerebral blood flow suggest that there are underlying differences in sensorimotor function in developmental stammerers whose symptoms commonly appear during the period of intensive language acquisition around the third and fourth year. Emotional tensions may exacerbate the disturbance, but equally psychological growth is adversely affected by the handicap. Abnormal motor control is confirmed by the exaggerated activity in the right hemisphere. The normal sequence of articulatory programming and motor preparation for single word reading is reversed. Absence of activation over the left auditory cortex supports the notion of impaired or diminished auditory feedback in the self-monitoring of speech seen in normal brains. Subcortical abnormalities are a feature of both developmental and acquired stammering.

scholarly journals Brain Activation During Reading in Deep Dyslexia: An MEG Study

2000 ◽  
Vol 12 (4) ◽  
pp. 622-634 ◽  
Author(s):  
Matti Laine ◽  
Riitta Salmelin ◽  
Päivi Helenius ◽  
Reijo Marttila
Keyword(s):  
Semantic Processing ◽  
Semantic Analysis ◽  
Right Hemisphere ◽  
Word Reading ◽  
Brain Activity ◽  
Temporal Cortex ◽  
Single Word ◽  
Lexical Semantic ◽  
Deep Dyslexia ◽  
Single Word Reading

Magnetoencephalographic (MEG) changes in cortical activity were studied in a chronic Finnish-speaking deep dyslexic patient during single-word and sentence reading. It has been hypothesized that in deep dyslexia, written word recognition and its lexical-semantic analysis are subserved by the intact right hemisphere. However, in our patient, as well as in most nonimpaired readers, lexical-semantic processing as measured by sentence-final semantic-incongruency detection was related to the left superior-temporal cortex activation. Activations around this same cortical area could be identified in single-word reading as well. Another factor relevant to deep dyslexic reading, the morphological complexity of the presented words, was also studied. The effect of morphology was observed only during the preparation for oral output. By performing repeated recordings 1 year apart, we were able to document significant variability in both the spontaneous activity and the evoked responses in the lesioned left hemisphere even though at the behavioural level, the patient's performance was stable. The observed variability emphasizes the importance of estimating consistency of brain activity both within and between measurements in brain-damaged individuals.

scholarly journals Cortical Effects of Shifting Letter Position in Letter Strings of Varying Length

2003 ◽  
Vol 15 (5) ◽  
pp. 731-746 ◽  
Author(s):  
Piers Cornelissen ◽  
Antti Tarkiainen ◽  
Päivi Helenius ◽  
Riitta Salmelin
Keyword(s):  
Word Length ◽  
Right Hemisphere ◽  
Word Reading ◽  
Temporal Dynamics ◽  
Temporal Cortex ◽  
Letter Position ◽  
Opposite Pattern ◽  
Spatio Temporal ◽  
Single Word Reading ◽  
The Right

Neuroimaging and lesion studies suggest that occipitotemporal brain areas play a necessary role in recognizing a wide variety of objects, be they faces, letters, numbers, or household items. However, many questions remain regarding the details of exactly what kinds of information are processed by the occipito-temporal cortex. Here, we address this question with respect to reading. Ten healthy adult subjects performed a single word reading task. We used whole-head magnetoencephalography to measure the spatio-temporal dynamics of brain responses, and investigated their sensitivity to: (1) lexicality (defined here as the difference between words and consonant strings), (2) word length, and (3) variation in letter position. Analysis revealed that midline occipital activity around 100 msec, consistent with low-level visual feature analysis, was insensitive to lexicality and variation in letter position, but was slightly affected by string length. Bilateral occipito-temporal activations around 150 msec were insensitive to lexicality and reacted to word length only in the timing (and not strength) of activation. However, vertical shifts in letter position revealed a hemispheric imbalance: The right hemisphere activation increased with the shifts, whereas the opposite pattern was evident in the left hemisphere. The results are discussed in the light of Caramazza and Hillis's (1990) model of early reading.

A Positron Emission Tomography Study of Silent and Oral Single Word Reading in Stuttering and Nonstuttering Adults

2000 ◽  
Vol 43 (4) ◽  
pp. 1038-1053 ◽  
Author(s):  
Luc F. De Nil ◽  
Robert M. Kroll ◽  
Shitij Kapur ◽  
Sylvain Houle
Keyword(s):  
Positron Emission Tomography ◽  
Right Hemisphere ◽  
Word Reading ◽  
Statistical Parametric Mapping ◽  
Anterior Cingulate ◽  
Emission Tomography ◽  
Single Word ◽  
Positron Emission ◽  
Single Word Reading ◽  
Group Comparisons

Over the last decade positron emission tomography (PET) has been used extensively for the study of language and other cognitive and sensorimotor processes in healthy and diseased individuals. In the present study, [ 15 O]H 2 O PET scanning was used to investigate the lateralization and functional distribution of cortical and subcortical activity involved in single word reading in stuttering and non-stuttering individuals. Ten right-handed male stuttering adults and matched nonstuttering individuals were instructed to read individually presented single words either silently or out loud. Subtraction of functional brain images obtained during each of the two reading tasks, and during a non-linguistic baseline task, was used to calculate within-group and between-group differences in regional cerebral blood flow by means of statistical parametric mapping. Increased activation in the left anterior cingulate cortex (ACC) was observed during silent reading in the stuttering speakers but not in the nonstuttering group. Because of the hypothesized role of the ACC in selective attention and covert articulatory practice, it is suggested that the observed increased ACC activation in the stuttering individuals reflects the presence of cognitive anticipatory reactions related to stuttering. During the oral reading task, within-group comparisons showed bilateral cortical and subcortical activation in both the stuttering and the nonstuttering speakers. Between-group comparisons showed a proportionally greater left hemisphere activation in the nonstuttering speakers, and a proportionally greater right hemisphere activation in the stuttering individuals. The results of the present study provide qualified support for the hypothesis that stuttering adults show atypical lateralization of language processes.

Differential components of sentence comprehension: Beyond single word reading and memory

NeuroImage ◽  
2006 ◽  
Vol 29 (2) ◽  
pp. 429-438 ◽  
Author(s):  
L.E. Cutting ◽  
A.M. Clements ◽  
S. Courtney ◽  
S.L. Rimrodt ◽  
J.G.B. Schafer ◽  
...  
Keyword(s):  
Sentence Comprehension ◽  
Word Reading ◽  
Single Word ◽  
Single Word Reading

Investigation of the Functional Neuroanatomy of Single Word Reading and Its Development

2018 ◽  
pp. 203-223
Author(s):  
Erica D. Palmer ◽  
Timothy T. Brown ◽  
Steven E. Petersen ◽  
Bradley L Schlaggar
Keyword(s):  
Word Reading ◽  
Functional Neuroanatomy ◽  
Single Word ◽  
Single Word Reading

The Effects of Direct Instruction on the Single-Word Reading Skills of Children Who Require Augmentative and Alternative Communication

2004 ◽  
Vol 47 (6) ◽  
pp. 1424-1439 ◽  
Author(s):  
Karen A. Fallon ◽  
Janice Light ◽  
David McNaughton ◽  
Kathryn Drager ◽  
Carol Hammer
Keyword(s):  
Direct Instruction ◽  
Augmentative And Alternative Communication ◽  
Reading Skills ◽  
Word Reading ◽  
Instructional Program ◽  
Future Research ◽  
Single Subject ◽  
Single Word ◽  
Alternative Communication ◽  
Single Word Reading

Current literature suggests a lack of empirically validated strategies for teaching reading skills to children who use augmentative and alternative communication (AAC). The current study implemented a single-subject, multiple-probe-across-subjects design to investigate the effects of direct instruction in single-word reading on the performance of students who use AAC. The instructional program targeted the reading skills of 5 participants who had severe speech impairments and ranged in age from 9 to 14 years old. All 5 participants reached criterion for matching targeted written words to corresponding pictures. Three of the 5 participants demonstrated generalization of reading skills to novel-word reading, and 4 of the 5 generalized reading skills to book contexts. Implications and directions for future research are discussed.

scholarly journals Effects of rTMS Conditioning over the Fronto-parietal Network on Motor versus Visual Attention

2007 ◽  
Vol 19 (3) ◽  
pp. 513-524 ◽  
Author(s):  
Elisabeth Rounis ◽  
Kielan Yarrow ◽  
John C. Rothwell
Keyword(s):  
Visual Attention ◽  
Parietal Cortex ◽  
Posterior Parietal Cortex ◽  
Right Hemisphere ◽  
Repetitive Transcranial Magnetic Stimulation ◽  
Motor Preparation ◽  
Attention Task ◽  
Spatial Orienting ◽  
Left Dlpfc ◽  
The Right

Many studies have shown that visuospatial orienting attention depends on a network of frontal and parietal areas in the right hemisphere. Rushworth et al. [Rushworth, M. F., Krams, M., & Passingham, R. E. The attentional role of the left parietal cortex: The distinct lateralization and localization of motor attention in the human brain. Journal of Cognitive Neuroscience, 13, 698–710, 2001] have recently provided evidence for a left-lateralized network of parietal areas involved in motor attention. Using two variants of a cued reaction time (RT) task, we set out to investigate whether high-frequency repetitive transcranial magnetic stimulation (rTMS; 5 Hz) delivered “off-line” in a virtual lesion paradigm over the right or left dorsolateral prefrontal cortex (DLPFC) or the posterior parietal cortex (PPC) would affect performance in a motor versus a visual attention task. Although rTMS over the DLPFC on either side did not affect RT performance on a spatial orienting task, it did lead to an increase in the RTs of invalidly cued trials in a motor attention task when delivered to the left DLPFC. The opposite effect was found when rTMS was delivered to the PPC: In this case, conditioning the right PPC led to increased RTs in invalidly cued trials located in the left hemispace, in the spatial orienting task. rTMS over the PPC on either side did not affect performance in the motor attention task. This double dissociation was evident in the first 10 min after rTMS conditioning. These results enhance our understanding of the networks associated with attention. They provide evidence of a role for the left DLPFC in the mechanisms of motor preparation, and confirm Mesulam's original proposal for a right PPC dominance in spatial attention [Mesulam, M. M. A cortical network for directed attention and unilateral neglect. Annals of Neurology, 10, 309–325, 1981].

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