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Successful adaptation to wearing dentures with palatal coverage may be associated with cortical activity changes related to tongue motor control. The purpose was to investigate the brain activity changes during tongue movement in response to a new oral environment. Twenty-eight fully dentate subjects (mean age: 28.6-years-old) who had no experience with removable dentures wore experimental palatal plates for 7 days. We measured tongue motor dexterity, difficulty with tongue movement, and brain activity using functional magnetic resonance imaging during tongue movement at pre-insertion (Day 0), as well as immediately (Day 1), 3 days (Day 3), and 7 days (Day 7) post-insertion. Difficulty with tongue movement was significantly higher on Day 1 than on Days 0, 3, and 7. In the subtraction analysis of brain activity across each day, activations in the angular gyrus and right precuneus on Day 1 were significantly higher than on Day 7. Tongue motor impairment induced activation of the angular gyrus, which was associated with monitoring of the tongue's spatial information, as well as the activation of the precuneus, which was associated with constructing the tongue motor imagery. As the tongue regained the smoothness in its motor functions, the activation of the angular gyrus and precuneus decreased.

Noncoding repeat expansions cause various neuromuscular diseases, including myotonic dystrophies, fragile X tremor/ataxia syndrome, some spinocerebellar ataxias, amyotrophic lateral sclerosis and benign adult familial myoclonic epilepsies. Inspired by the striking similarities in the clinical and neuroimaging findings between neuronal intranuclear inclusion disease (NIID) and fragile X tremor/ataxia syndrome caused by noncoding CGG repeat expansions in FMR1, we directly searched for repeat expansion mutations and identified noncoding CGG repeat expansions in NBPF19 (NOTCH2NLC) as the causative mutations for NIID. Further prompted by the similarities in the clinical and neuroimaging findings with NIID, we identified similar noncoding CGG repeat expansions in two other diseases: oculopharyngeal myopathy with leukoencephalopathy and oculopharyngodistal myopathy, in LOC642361/NUTM2B-AS1 and LRP12, respectively. These findings expand our knowledge of the clinical spectra of diseases caused by expansions of the same repeat motif, and further highlight how directly searching for expanded repeats can help identify mutations underlying diseases.

In children, storytelling provides many psychological and educational benefits, such as enhanced imagination to help visualize spoken words, improved vocabulary, and more refined communication skills. However, the brain mechanisms underlying the effects of storytelling on children are not clear. In this study, the effects of storytelling on the brains of children were assessed by using near-infrared spectroscopy (NIRS). Results indicated significant decreases of the blood flow in the bilateral prefrontal areas during picture-book reading when the subjects were familiarized in comparison to the cases of the subject naïve to the stories. However, no significant differences in the blood flow were found during storytelling between the subjects naïve and familiarized to the stories. The results indicated more sustained brain activation to storytelling in comparison with picture-book reading, suggesting possible advantages of storytelling as a psychological and educational medium in children.

Imitative stimuli presented from a first-person perspective (FPP) produce stronger visuomotor effects than those presented from a third-person perspective (TPP) due to the relatively greater response of the mirror neuron system (MNS) to FPP stimuli. Some previous studies utilizing TPP stimuli have reported no differences in MNS activity between moving and static bodies' stimuli. However, few studies have compared visuomotor effects of such stimuli when presented in the FPP. To clarify this issue, we measured cortical activation in 17 participants during a functional magnetic resonance imaging (MRI) imitation task involving three conditions: moving (a lifting finger was presented), static (an "X" appeared on a static finger), and control (an "X" appeared on a button). All stimuli were presented from the FPP or TPP. Participants were asked to lift the finger corresponding to the imitative stimulus. In the FPP condition, moving stimuli elicited greater MNS activation than static stimuli. Furthermore, such movement effects were stronger in the MNS and insula (a region associated with body-ownership) for FPP stimuli than for TPP stimuli. Psychophysiological interaction analysis revealed increased connectivity between the MNS and insula for moving stimuli in the FPP condition. These findings suggest that bodily movements presented in the FPP elicit a greater visuomotor response than static body presented in the FPP, and that the visuomotor effects of bodily movements were greater in the FPP condition than in the TPP condition. Our analyses further indicated that such responses are processed via the neural system underlying body-ownership. Hum Brain Mapp 38:6218-6229, 2017. © 2017 Wiley Periodicals, Inc., (© 2017 Wiley Periodicals, Inc.)

Areas 5 and 7 are the association cortices which are located in the parietal lobe and process somatosensory and visual information, respectively. The location of area 7 differ in the Brodmann's human and monkey brain map, in the human brain map area 7 is located in the superior parietal lobe, while it is in the inferior parietal lobe in the monkey brain map. Thus, it is difficult to discuss the function of these areas.

Patients with unilateral sensorineural hearing loss (UHL) often complain of hearing difficulties in noisy environments. To clarify this, we compared brain activation in patients with UHL with that of healthy participants during speech perception in a noisy environment, using functional magnetic resonance imaging (fMRI). A pure tone of 1 kHz, or 14 monosyllabic speech sounds at 65‒70 dB accompanied by MRI scan noise at 75 dB, were presented to both ears for 1 second each and participants were instructed to press a button when they could hear the pure tone or speech sound. Based on the activation areas of healthy participants, the primary auditory cortex, the anterior auditory association areas, and the posterior auditory association areas were set as regions of interest (ROI). In each of these regions, we compared brain activity between healthy participants and patients with UHL. The results revealed that patients with right-side UHL showed different brain activity in the right posterior auditory area during perception of pure tones versus monosyllables. Clinically, left-side and right-side UHL are not presently differentiated and are similarly diagnosed and treated; however, the results of this study suggest that a lateralityspecific treatment should be chosen.

Unlabelled: The architectonic subdivisions of the brain are believed to be functional modules, each processing parts of global functions. Previously, we showed that neurons in different regions operate in different firing regimes in monkeys. It is possible that firing regimes reflect differences in underlying information processing, and consequently the firing regimes in homologous regions across animal species might be similar. We analyzed neuronal spike trains recorded from behaving mice, rats, cats, and monkeys. The firing regularity differed systematically, with differences across regions in one species being greater than the differences in similar areas across species. Neuronal firing was consistently most regular in motor areas, nearly random in visual and prefrontal/medial prefrontal cortical areas, and bursting in the hippocampus in all animals examined. This suggests that firing regularity (or irregularity) plays a key role in neural computation in each functional subdivision, depending on the types of information being carried., Significance Statement: By analyzing neuronal spike trains recorded from mice, rats, cats, and monkeys, we found that different brain regions have intrinsically different firing regimes that are more similar in homologous areas across species than across areas in one species. Because different regions in the brain are specialized for different functions, the present finding suggests that the different activity regimes of neurons are important for supporting different functions, so that appropriate neuronal codes can be used for different modalities., (Copyright © 2016 the authors 0270-6474/16/365737-12$15.00/0.)

It is well known that shortened dental arch decreases masticatory function. However, its potential to change brain activity during mastication is unknown. The present study investigates the effect of a shortened posterior dental arch with mandibular removable partial dentures (RPDs) on brain activity during gum chewing. Eleven subjects with missing mandibular molars (mean age, 66.1 years) on both sides received experimental RPDs with interchangeable artificial molars in a crossover trial design. Brain activity during gum chewing with RPDs containing (full dental arch) and lacking artificial molars (shortened dental arch) was measured using functional magnetic resonance imaging. Additionally, masticatory function was evaluated for each dental arch type. Food comminuting and mixing ability and the perceived chewing ability were significantly lower in subjects with a shortened dental arch than those with a full dental arch (P < 0.05). Brain activation during gum chewing with the full dental arch occurred in the middle frontal gyrus, primary sensorimotor cortex extending to the pre-central gyrus, supplementary motor area, putamen, insula and cerebellum. However, middle frontal gyrus activation was not observed during gum chewing with the shortened dental arch. These results suggest that shortened dental arch affects human brain activity in the middle frontal gyrus during gum chewing, and the decreased middle frontal gyrus activation may be associated with decreased masticatory function., (© 2014 John Wiley & Sons Ltd.)

We assessed the effect of teeth clenching on handgrip force behaviorally, and investigated cortical activity during the occurrence of facilitatory effects using functional magnetic resonance imaging (fMRI). Twenty-three participants were assessed as to whether they had habitual teeth clenching during maximal voluntary contraction (MVC) exertion, and 21 of them were identified to have such a habit. For those participants, behavioral testing showed that MVC with clenching was greater compared with without clenching (approximately 108% greater on average). Next, cortical activity was measured under gripping with clenching (GwC), gripping without clenching (GwoC), and teeth clenching (C) conditions. We found that the activity of the hand region in primary motor cortex (M1), cingulate motor area/supplementary motor area (CMA/SMA) and anterior cerebellum (AC) was greater in contrast of GwC vs. (GwoC+C). Furthermore, significant correlation was observed between the increasing ratio of the handgrip force and the % signal change in the hand region of M1 and AC, but not in CMA/SMA. These results suggest that the activation in the hand region of M1 and AC may facilitate the spinal motoneurons, and the activation in the hand region in M1 by clenching may be due to a signal from CMA/SMA., (Copyright © 2013 Elsevier Ireland Ltd and the Japan Neuroscience Society. All rights reserved.)

Learning is the process of accumulating information. Repetition can make the process of retrieving information more efficient. The mechanisms by which repetition facilitates the retrieval process, however, are not yet clear. Here, we used event-related functional magnetic resonance imaging to investigate the effects of repetition on cued recall. In this study, participants were asked to encode visually presented semantically unrelated word pairs. The word presented on the left side served as the cue, and the word presented on the right side was the target. In the first test phase, participants were presented with the cue and asked to recall the associated word (target) from the study phase. The second test phase was performed 20 min later using the same method. Participants responded orally during the interval between image acquisitions, and no feedback was provided. Neural activity for identical stimuli and responses across the two tests were compared. As compared with the first test phase, the right dorsolateral prefrontal, bilateral inferior parietal, and precuneus regions showed greater activity and the left inferior frontal areas showed reduced activity during the second test phase. These shifts in neural activity that occurred with repetition may reflect the dynamics of the retrieval process., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Background: Amyloid beta (Aβ) accumulates in the human brain in an age-dependent manner during normal aging. However, Aβ accumulation has not been observed in rodents during normal aging. Tree shrews, the experimental animals studied here, are as small as rats but have a longer life span than rodents., Methods: We investigated Aβ accumulations in the brains of young and aged tree shrews by amyloid histochemistry and immunohistochemistry using antibodies to Aβ-42, Aβ-40, Aβ-16 and amyloid precursor protein (APP)., Results: In the brain of young tree shrews, there were no Aβ- immunoreactive (-ir) and APP-ir profiles. In the brains of aged tree shrews, Aβ-42-ir neuronal profiles were observed in the cortex, subiculum, basal ganglia, mammillary body and hypothalamus, but there were only a few weak Congo red-positive amyloid deposits. Aβ-42-, Aβ-40-, Aβ-16- and APP-ir blood vessels were observed., Conclusions: An early stage of amyloid accumulation occurs in the brains of aged tree shrews, indicating that this animal may be a good model for studying the start of Aβ accumulation.

This event-related fMRI study was conducted to examine the blood-oxygen-level-dependent responses to the processing of auditory onomatopoeic sounds. We used a sound categorization task in which the participants heard four types of stimuli: onomatopoeic sounds, nouns (verbal), animal (nonverbal) sounds, and pure tone/noise (control). By discriminating between the categories of target sounds (birds/nonbirds), the nouns resulted in activations in the left anterior superior temporal gyrus (STG), whereas the animal sounds resulted in activations in the bilateral superior temporal sulcus (STS) and the left inferior frontal gyrus (IFG). In contrast, the onomatopoeias activated extensive brain regions, including the left anterior STG, the region from the bilateral STS to the middle temporal gyrus, and the bilateral IFG. The onomatopoeic sounds showed greater activation in the right middle STS than did the nouns and environmental sounds. These results indicate that onomatopoeic sounds are processed by extensive brain regions involved in the processing of both verbal and nonverbal sounds. Thus, we can posit that onomatopoeic sounds can serve as a bridge between nouns and animal sounds. This is the first evidence to demonstrate the way in which onomatopoeic sounds are processed in the human brain.

Antisaccade tasks require a subject to inhibit a saccade toward a briefly appearing peripheral target and instead to immediately generate a saccade to an equivalent point in the opposite hemifield. Using functional magnetic resonance imaging (fMRI), we investigated the neural networks required to inhibit reflexive saccades and to voluntarily generate saccades. The results demonstrated that saccade and antisaccade tasks often bilaterally activate frontal, parietal and supplementary eye fields, lenticular nuclei and occipital cortex. Additional activation of bilateral dorsolateral prefrontal cortices, supramarginal gyri, anterior cingulate cortices and thalamus was observed during antisaccade tasks. These results indicate that fronto-parietal and fronto-striato-thalamo-cortical circuits are involved in antisaccade tasks. The fronto-parietal circuit is thought to be related to the planning of saccadic eye movements that involve attentional control, while the fronto-striato-thalamo-cortical circuits connect to cortical region as a feedback network. We speculate that the abnormalities in spatial attention and eye movement control observed in schizophrenia stem from dysfunctions in the fronto-parietal and fronto-striato-thalamo-cortical circuits.

In order to separate the cognitive processes associated with phonological encoding and the use of a visual word form lexicon in reading, it is desirable to compare the processing of words presented in a visually familiar form with words in a visually unfamiliar form. Japanese Kana orthography offers this possibility. Two phonologically equivalent but visually dissimilar syllabaries allow the writing of, for example, foreign loanwords in two ways, only one of which is visually familiar. Familiarly written words, unfamiliarly written words, and pseudowords were presented in both Kana syllabaries (yielding six conditions in total) to participants during an fMRI measurement with a silent articulation task (Experiment 1) and a phonological lexical decision task (Experiment 2) using an event-related design. Consistent over two experimental tasks, the three different stimulus types (familiar, unfamiliar, and pseudoword) were found to activate selectively different brain regions previously associated with phonological encoding and word retrieval or meaning. Compatible with the predictions of the dual-route model for reading, pseudowords and visually unfamiliar words, which have to be read using phonological assembly, caused an increase in brain activity in left inferior frontal regions (BA 44/47), as compared to visually familiar words. Visually familiar and unfamiliar words were found to activate a range of areas associated with lexico-semantic processing more strongly than pseudowords, such as the left and right temporo-parietal region (BA 39/40), a region in the left middle/inferior temporal gyrus (BA 20/21), and the posterior cingulate (BA 31).

The purpose of this study was to examine brain areas involved in simple arithmetic, and to compare these areas between adults and children. Eight children (four girls and four boys; age, 9-14 years) and eight adults (four women and four men; age, 40-49 years) were subjected to this study. Functional magnetic resonance imaging (fMRI) was performed during mental calculation of addition, subtraction, and multiplication of single digits. In each group, the left middle frontal, bilateral inferior temporal and bilateral lateral occipital cortices were activated during each task. The adult group showed activation of the right frontal cortex during addition and multiplication tasks, but the children group did not. Activation of the intraparietal cortex was observed in the adult group during each task. Although, activation patterns were slightly different among tasks, as well as between groups, only a small number of areas showed statistically significant differences. The results indicate that cortical networks involved in simple arithmetic are similar among arithmetic operations, and may not show significant changes in the structure during the second decade of life.

We examined the cortical areas showing increased activation related to axis orientation discrimination in hand movement and perception by positron emission tomography (PET) in right-handed normal human subjects while they performed a hand orientation (HO) task and an orientation discrimination (OD) task. In the OD task, fields in the parietal cortex and a field in the inferior frontal gyrus showed increased activation relative to the control task. In the HO task, fields in the intraparietal sulcus, the inferior and middle frontal gyri, the fusiform gyrus and the middle temporal gyrus showed increased activation relative to the control task. The results indicate that areas involved in axis orientation discrimination seemed to be segregated in the parietal cortex, with one field in the left intraparietal sulcus related to hand movement and another field in the right intraparietal sulcus related to perception.

We report the cloning, sequence analysis, and developmental expression pattern of lim1, a member of the LIM class homeobox gene family in the mouse. lim1 cDNA encodes a predicted 406 amino acid protein that is 93% identical with the product of the Xenopus LIM class homeobox gene Xlim1. We have characterized lim1 expression from day 8.5 post coitum onward. Northern blot analysis of RNA transcripts indicates that lim1 is expressed both during embryogenesis and in the adult brain. Analysis by whole-mount and section in situ hybridization shows lim1 expression in the central nervous system from the telencephalon through the spinal cord and in the developing excretory system including pronephric region, mesonephros, nephric duct, and metanephros. In the metanephros, lim1 is strongly expressed in renal vesicles and S-shaped bodies, and transcripts are also detected in the ureteric branches.

After photolabelling of purified bovine brain particulate cGMP stimulated phosphodiesterase (PDE) with [32P]cGMP, incubation with V8 Endoproteinase Glu-C produced several fragments; most of the [32P] was associated with smaller fragments (approximately 12-14 kDa), and some occasionally with larger fragments (approximately 55-57 kDa). Partial amino acid sequences were determined for the smaller photolabelled fragments and other peptides. On Western immunoblots, affinity-purified antibodies against a synthetic peptide with a sequence matching part of that of the approximately 12-14 kDa photolabelled material reacted with intact PDE and the approximately 12-14 kDa and approximately 55-57 kDa fragments. Several partial cDNA clones encoding the cGMP-stimulated PDE were isolated from a Lambda Zap II bovine brain cDNA library. Deduced amino acid sequence from one cDNA clone, lambda cGS 3-1, as well as the partial sequence of the approximately 12-14 kDa and other fragments, exhibited considerable identity with amino acid residues 311-921 of the cardiac cGMP-stimulated PDE (Trong et al., 1990), including the putative cGMP-binding domain (Charbonneau et al., 1990). These results further define this cGMP-binding domain and suggest that different cGMP-stimulated PDEs will exhibit considerable homology, at least in their cGMP-binding region(s) and catalytic domains.

Prosthodontic treatment success depends on patients' ability to adapt to an altered oral environment containing removable prostheses. We investigated adaptive chewing-related brain activity changes in response to a new oral environment. Twenty-eight fully dentate subjects (mean age: 28·6 years) wore experimental denture-base palatal plates (3 mm thick), for 7 days. We measured food mixing ability and cycle time, and assessed brain activity by functional magnetic resonance imaging during chewing at pre-insertion (Day 0), and immediately (Day 1), 3 days (Day 3) and 7 days (Day 7) after insertion. Food mixing ability significantly decreased and cycle time increased on Day 1 as compared to Day 0 ( P < 0·001) and tended to recover to Day 0 level by Day 7. Brain activation in the right face primary sensorimotor cortex and putamen significantly decreased on Day 1 as compared to Day 0 ( P < 0·001) and recovered to Day 0 level by Day 7. Brain activation in the left face primary sensorimotor cortex, putamen, anterior cingulate gyrus ( ACG) and right posterior medial frontal cortex ( pMFC) significantly decreased on Day 1 as compared to Day 0 ( P < 0·001) and did not recover by Day 7. Thus, oral environment changes involving palate covering affected chewing and induced adaptive brain activity changes in the face primary sensorimotor cortex and putamen, possibly associated with motor learning. As ACG and pMFC activity remained unrecovered by 7 days after plate insertion, automatisation of chewing while wearing a palatal plate may require longer adaptation periods. [ABSTRACT FROM AUTHOR]