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1.
Sci Rep ; 13(1): 9363, 2023 06 08.
Artículo en Inglés | MEDLINE | ID: mdl-37291199

RESUMEN

The smartphone has become an indispensable part of everyday life. It enables endless possibilities and offers persistent access to a multiplicity of entertainment, information, and social contacts. The development towards a greater use and a persistent presence of the smartphone does not only lead to advantages, but also raises potential for negative consequences and a negative influence on attention. In this research, the hypothesis of the mere smartphone presence leading to cognitive costs and a lower attention is being tested. The smartphone may use limited cognitive resources and consequently lead to a lower cognitive performance. To investigate this hypothesis, participants aged 20-34 perform a concentration and attention test in the presence and absence of a smartphone. The results of the conducted experiment imply that the mere presence of a smartphone results in lower cognitive performance, which supports the hypothesis of the smartphone presence using limited cognitive resources. The study as well as the subsequent results and the resulting practical implications are presented and discussed in this paper.


Asunto(s)
Atención , Teléfono Inteligente , Humanos
2.
Trends Neurosci Educ ; 25: 100160, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34844692

RESUMEN

BACKGROUND: Although breaks are essential to restoring cognitive and psychological conditions for learning, short breaks within school lessons are not established and the specificity of effects has not often been investigated. Therefore, the effects of a physical activity (Study 1) and a mindfulness intervention (Study 2) were investigated. PROCEDURE: By an intervention-control group design, the effects of daily 10-min physical activity (Study 1: N = 162, 4th grade) and mindfulness breaks (Study 2: N = 79, 5th grade) were implemented within regular school lessons over a 2-week time period to research the impact on attention, reading comprehension, and self-esteem. RESULTS: In the physical activity intervention children's attention improved (attention-processing speed: p < .004, ηp2 = .05, attention-performance: p < .025, ηp2 = .03), and in the mindfulness intervention reading comprehension improved (p < .012, ηp2 = .08) compared to the controls. Results further indicated that self-esteem moderated the relationship between groups and attention improvement in study 1. CONCLUSION: Classroom-based short physical and mindfulness breaks could support attention and reading comprehension, which are known to support overall academic success.


Asunto(s)
Atención Plena , Lectura , Atención , Niño , Comprensión , Ejercicio Físico/psicología , Humanos , Instituciones Académicas
3.
Ann Dyslexia ; 71(3): 458-482, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33977420

RESUMEN

Early intervention for children with reading impairments is crucial in order to achieve reading improvements and avoid school failure. One line of reading intervention research focuses on the experimental manipulation of reading rate through a text-fading training approach. Considering relevant reading-related predictors (i.e., orthographic knowledge and rapid automatized naming; RAN), we aim at evaluating the text-fading training's efficiency for a sample of German reading-impaired third graders (n = 120). The purpose of the present study was to examine (1) the predictive value of orthographic knowledge and RAN and their contribution of explained variance in comprehension performance during training, (2) text-fading training effects on reading rate and comprehension in a pre-post comparison, and (3) (lasting) text-fading training effects at word and sentence level in a pre-post-follow-up design. Results of structural models indicated RAN to be significantly related to comprehension performance for the experimental group, whereas no sufficient regression weight was found for orthographic knowledge. A reverse pattern was found for the self-paced group. No significant improvements regarding reading rate and comprehension were revealed for the experimental group after training. However, significant positive effects on word and sentence level at post-test time point indicate stronger reading improvements for the experimental compared to the control group. The retention of training gains was indicated at sentence-level reading 6 months after the training. Possible explanations for the presented positive training effects as well as the mixed results for reading rate, comprehension, and follow-up preservation are discussed.


Asunto(s)
Dislexia , Lectura , Niño , Comprensión , Dislexia/terapia , Humanos , Lenguaje , Tiempo de Reacción
4.
Neural Plast ; 2019: 4826238, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30911290

RESUMEN

Background: Feedback postural control depends upon information from somatosensation, vision, and the vestibular system that are weighted depending on their relative importance within the central nervous system. Following loss of any sensory component, the weighting changes, e.g., when suffering a vestibular loss, the most common notion is that patients become more dependent on visual cues for maintaining postural control. Dizziness and disequilibrium are common after surgery in schwannoma patients, which could be due to interpretation of the remaining sensory systems involved in feedback-dependent postural control and spatial orientation. Objective: To compare visual dependency in spatial orientation and postural control in patients suffering from unilateral vestibular loss within different time frames. Methods: Patients scheduled for schwannoma surgery: group 1 (n = 27) with no vestibular function prior to surgery (lost through years), group 2 (n = 12) with remaining vestibular function at the time of surgery (fast deafferentation), and group 3 (n = 18) with remaining function that was lost through gentamicin installations in the middle ear (slow deafferentation). All patients performed vibratory posturography and rod and frame investigation before surgery and 6 months after surgery. Results: Postural control improved after surgery in patients that suffered a slow deafferentation (groups 1 and 3) (p < 0.001). Patients that suffered fast loss of remaining vestibular function (group 2) became less visual field dependent after surgery (p ≤ 0.035) and were less able to maintain stability compared with group 1 (p = 0.010) and group 3 (p = 0.010). Conclusions: The nature and time course of vestibular deafferentation influence the weighting of remaining sensory systems in order to maintain postural control and spatial orientation.


Asunto(s)
Neurilemoma/fisiopatología , Equilibrio Postural/fisiología , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neurilemoma/cirugía , Pruebas de Función Vestibular
5.
J Vestib Res ; 27(5-6): 313-325, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29400686

RESUMEN

OBJECT: To evaluate post-surgical postural stability when treating patients with remaining vestibular function with intratympanic gentamicin (PREHAB) prior to schwannoma surgery. METHOD: 44 consecutive patients with some form remaining vestibular function scheduled for vestibular schwannoma surgery. 20 were medically deafferented with intratympanic gentamicin before surgery and 24 were not. Both groups were of the same age, had the same tumor size, same type of surgery, and same perioperative sensory rehabilitation (training exercises), and no surgical complications. Postural stability measured as energy expenditure while standing on a force platform during vibratory stimulation of the calf muscles, performed prior to surgery (or gentamicin treatment) and 6 months after surgery. RESULTS: Patients pretreated with gentamicin had significantly better postural stability at the time for follow-up (p < 0.05) and displayed a better adaptive capacity when faced with a postural challenge (p < 0.01). They were also able to use vision more efficiently to control their stability (p < 0.05). CONCLUSIONS: By separating the sensory loss (through intratympanic gentamicin, that ablates the remaining vestibular function) from the intracranial surgical trauma, the postural control system benefited from a better short-term (adaptation) and long-term (habituation) recovery, when experiencing a postural challenge or resolving a sensory conflict. The benefits could be attributed to; active and continuous motor learning as the vestibular function slowly attenuates; no concomitant central nervous dysfunction due to effects from neurosurgery, thus allowing time for a separate unimpeded recovery process with more limited challenges and objectives; and the initiation and certain progression of sensory reweighting processes allowed prior to surgery. In contrast, worse compensation could be due to; immobilization from nausea after surgery, harmful amount of stress and cognitive dysfunction from the combination of surgical and sensory trauma and an abrupt vestibular deafferentation and its consequences on sensory reweighting.


Asunto(s)
Antibacterianos , Gentamicinas , Neuroma Acústico/terapia , Equilibrio Postural/fisiología , Simpatectomía Química , Vestíbulo del Laberinto/fisiología , Adaptación Fisiológica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neuroma Acústico/fisiopatología , Neuroma Acústico/rehabilitación , Neuroma Acústico/cirugía , Cuidados Posoperatorios , Cuidados Preoperatorios , Recuperación de la Función/fisiología , Estudios Retrospectivos
6.
Front Psychol ; 9: 2656, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30671001

RESUMEN

Human beings are supposed to possess an approximate number system (ANS) dedicated to extracting and representing approximate numerical magnitude information as well as an object tracking system (OTS) for the rapid and accurate enumeration of small sets. It is assumed that the OTS and the ANS independently contribute to the acquisition of more elaborate numerical concepts. Chinese children have been shown to exhibit more elaborate numerical concepts than their non-Chinese peers, but it is still an open question whether similar cross-national differences exist with regard to the underlying systems, namely the ANS and the OTS. In the present study, we investigated this question by comparing Chinese and German preschool children with regard to their performance in a non-symbolic numerical magnitude comparison task (assessing the ANS) and in an enumeration task (assessing the OTS). In addition, we compared children's counting skills. To ensure that possible between-group differences could not be explained by differences in more general performance factors, we also assessed children's reasoning ability and processing speed. Chinese children showed a better counting performance and a more accurate performance in the non-symbolic numerical magnitude comparison task. These differences in performance could not be ascribed to differences in reasoning abilities and processing speed. In contrast, Chinese and German children did not differ significantly in the enumeration of small sets. The superior counting performance of Chinese children was thus found to be reflected in the ANS but not in the OTS.

7.
PLoS One ; 12(4): e0174991, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28384191

RESUMEN

Human beings are assumed to possess an approximate number system (ANS) dedicated to extracting and representing approximate numerical magnitude information. The ANS is assumed to be fundamental to arithmetic learning and has been shown to be associated with arithmetic performance. It is, however, still a matter of debate whether better arithmetic skills are reflected in the ANS. To address this issue, Chinese and German adults were compared regarding their performance in simple arithmetic tasks and in a non-symbolic numerical magnitude comparison task. Chinese participants showed a better performance in solving simple arithmetic tasks and faster reaction times in the non-symbolic numerical magnitude comparison task without making more errors than their German peers. These differences in performance could not be ascribed to differences in general cognitive abilities. Better arithmetic skills were thus found to be accompanied by a higher speed of retrieving non-symbolic numerical magnitude knowledge but not by a higher precision of non-symbolic numerical magnitude representations. The group difference in the speed of retrieving non-symbolic numerical magnitude knowledge was fully mediated by the performance in arithmetic tasks, suggesting that arithmetic skills shape non-symbolic numerical magnitude processing skills.


Asunto(s)
Matemática , Adolescente , Adulto , China , Femenino , Alemania , Humanos , Masculino , Tiempo de Reacción , Adulto Joven
8.
Front Psychol ; 7: 1337, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27630606

RESUMEN

Symbolic numerical magnitude processing skills are assumed to be fundamental to arithmetic learning. It is, however, still an open question whether better arithmetic skills are reflected in symbolic numerical magnitude processing skills. To address this issue, Chinese and German third graders were compared regarding their performance in arithmetic tasks and in a symbolic numerical magnitude comparison task. Chinese children performed better in the arithmetic tasks and were faster in deciding which one of two Arabic numbers was numerically larger. The group difference in symbolic numerical magnitude processing was fully mediated by the performance in arithmetic tasks. We assume that a higher degree of familiarity with arithmetic in Chinese compared to German children leads to a higher speed of retrieving symbolic numerical magnitude knowledge.

9.
Ear Hear ; 37(6): 744-750, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27438868

RESUMEN

OBJECTIVE: To evaluate auditory and vestibular function after presurgical treatment with gentamicin in schwannoma patients. BACKGROUND: The vestibular PREHAB protocol aims at diminishing the remaining vestibular function before vestibular schwannoma surgery, to ensure less acute symptoms from surgery, and initiate a more efficient vestibular rehabilitation already before surgery. However, the potential cochleotoxicity of gentamicin is a concern, since modern schwannoma surgery strives to preserve hearing. STUDY DESIGN: Retrospective study. SETTING: University hospital. PATIENTS: Seventeen patients diagnosed with vestibular schwannoma between 2004 and 2011, and took part in vestibular PREHAB program. The patients were of age 21 to 66 years (mean 48.8), 9 females and 8 males. INTERVENTION: Intratympanic gentamicin installations before surgery as part of the vestibular PREHAB. MAIN OUTCOME MEASURES: Hearing thresholds, word recognition score, caloric response, subjective visual vertical and horizontal, cVEMP, and vestibular impulse tests. RESULTS: Combined analysis of frequency and hearing threshold showed a significant decrease after gentamicin therapy (p < 0.001). Pure-tone average decreased with 7.1 ± 8.5 dB (p = 0.004), and speech recognition with 10%. The treatment resulted in unilateral vestibular deafferentation with no notable reaction to bithermal caloric irrigation (reduction 64%, p < 0.001), loss of the vestibulo-ocular response measured by the head-impulse test, and deviation of subjective horizontal/vertical to the side of the lesion (+2.2 degrees, p = 0.010). CONCLUSIONS: Intratympanic installations of gentamicin, as part of the vestibular PREHAB, result in unilateral vestibular deafferentation, but constitute a definite risk for high-frequency hearing loss. The hearing results are in line with those reported upon when treating Menière's disease.


Asunto(s)
Antibacterianos/efectos adversos , Gentamicinas/efectos adversos , Pérdida Auditiva de Alta Frecuencia/inducido químicamente , Neuroma Acústico/cirugía , Cuidados Preoperatorios , Potenciales Vestibulares Miogénicos Evocados/fisiología , Enfermedades del Nervio Vestibulococlear/inducido químicamente , Adulto , Anciano , Antibacterianos/administración & dosificación , Audiometría de Tonos Puros , Umbral Auditivo , Pruebas Calóricas , Femenino , Gentamicinas/administración & dosificación , Humanos , Inyección Intratimpánica , Masculino , Persona de Mediana Edad , Reflejo Anormal , Reflejo Vestibuloocular/fisiología , Estudios Retrospectivos , Enfermedades del Nervio Vestibulococlear/fisiopatología , Adulto Joven
10.
World Neurosurg ; 94: 544-550.e2, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27443231

RESUMEN

OBJECTIVE: Outcome after treatment of vestibular schwannomas can be evaluated by health providers as mortality, recurrence, performance, and morbidity. Because mortality and recurrence are rare events, evaluation has to focus on performance and morbidity. The latter has mostly been reported by health providers. In the present study, we validate 2 new scales for patient-assessed performance and morbidity in comparison with different outcome tools, such as quality of life (QOL) (European Quality of Life-5 dimensions [EQ-5D]), facial nerve score, and work capacity. METHODS: There were 167 total patients in a retrospective (n = 90) and prospective (n = 50) cohort of surgically treated vestibular schwannomas. A new patient-assessed morbidity score (paMS), a patient-assessed Karnofsky score (paKPS), the patient-assessed QOL (EQ-5D) score, work capacity, and the House-Brackmann facial nerve score were used as outcome measures. Analysis of paMS components and their relation to other outcomes was done as uni- and multivariate analysis. RESULTS: All outcome instruments, except EQ-5D and paKPS, showed a significant decrease postoperatively. Only the facial nerve score (House-Brackmann facial nerve score) differed significantly between the retrospective and prospective cohorts. Out of the 16 components of the paMS, hearing dysfunction, tear dysfunction, balance dysfunction, and eye irritation were most often reported. Both paMS and EQ-5D correlated significantly with work capacity. CONCLUSIONS: Standard QOL and performance instruments may not be sufficiently sensitive or specific to measure outcome at the cohort level after surgical treatment of vestibular schwannomas. A morbidity score may yield more detailed information on symptoms that can be relevant for rehabilitation and occupational training after surgery.


Asunto(s)
Encuestas de Atención de la Salud/estadística & datos numéricos , Enfermedades del Sistema Nervioso/diagnóstico , Neuroma Acústico/diagnóstico , Neuroma Acústico/cirugía , Evaluación de Resultado en la Atención de Salud/métodos , Satisfacción del Paciente , Autoevaluación (Psicología) , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedades del Sistema Nervioso/etiología , Neuroma Acústico/complicaciones , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
11.
Front Psychol ; 6: 119, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25713554

RESUMEN

Previous studies used a text-fading procedure as a training tool with the goal to increase silent reading fluency (i.e., proficient reading rate and comprehension). In recently published studies, this procedure resulted in lasting reading enhancements for adult and adolescent research samples. However, studies working with children reported mixed results. While reading rate improvements were observable for Dutch reading children in a text-fading training study, reading fluency improvements in standardized reading tests post-training attributable to the fading manipulation were not detectable. These results raise the question of whether text-fading training is not effective for children or whether research design issues have concealed possible transfer effects. Hence, the present study sought to investigate possible transfer effects resulting from a text-fading based reading training program, using a modified research design. Over a period of 3 weeks, two groups of German third-graders read sentences either with an adaptive text-fading procedure or at their self-paced reading rate. A standardized test measuring reading fluency at the word, sentence, and text level was conducted pre- and post-training. Text level reading fluency improved for both groups equally. Post-training gains at the word level were found for the text-fading group, however, no significant interaction between groups was revealed for word reading fluency. Sentence level reading fluency gains were found for the text-fading group, which significantly differed from the group of children reading at their self-paced reading routine. These findings provide evidence for the efficacy of text-fading as a training method for sentence reading fluency improvement also for children.

12.
J Cogn Neurosci ; 27(2): 308-18, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25203270

RESUMEN

Neural systems involved in the processing of written language have been identified by a number of functional imaging studies. Structural changes in cortical anatomy that occur in the course of literacy acquisition, however, remain largely unknown. Here, we follow elementary school children over their first 2 years of formal reading instruction and use tensor-based morphometry to relate reading proficiency to cortical volume at baseline and follow-up measurement as well as to intraindividual longitudinal volume development between the two measurement time points. A positive relationship was found between baseline gray matter volume in the left superior temporal gyrus and subsequent changes in reading proficiency. Furthermore, a negative relationship was found between reading proficiency at the second measurement time point and intraindividual cortical volume development in the inferior parietal lobule and the precentral and postcentral gyri of the left hemisphere. These results are interpreted as evidence that reading acquisition is associated with preexisting structural differences as well as with experience-dependent structural changes involving dendritic and synaptic pruning.


Asunto(s)
Corteza Cerebral/anatomía & histología , Corteza Cerebral/crecimiento & desarrollo , Sustancia Gris/anatomía & histología , Sustancia Gris/crecimiento & desarrollo , Lectura , Niño , Desarrollo Infantil , Femenino , Estudios de Seguimiento , Humanos , Pruebas del Lenguaje , Estudios Longitudinales , Imagen por Resonancia Magnética , Masculino , Tamaño de los Órganos
13.
Front Psychol ; 4: 783, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24167498

RESUMEN

The approximate number system (ANS) is assumingly related to mathematical learning but evidence supporting this assumption is mixed. The inconsistent findings might be attributed to the fact that different measures have been used to assess the ANS and mathematical skills. Moreover, associations between the performance on a measure of the ANS and mathematical skills may be discontinuous, i.e., stronger for children with lower math scores than for children with higher math scores, and may change with age. The aim of the present study was to examine the development of the ANS and arithmetic skills in elementary school children and to investigate how the relationship between the ANS and arithmetic skills develops. Individual markers of children's ANS (internal Weber fractions and mean reaction times in a non-symbolic numerical comparison task) and addition skills were assessed in their first year of school and 1 year later. Children showed improvements in addition performance and in the internal Weber fractions, whereas mean reaction times in the non-symbolic numerical comparison task did not change significantly. While children's addition performance was associated with the internal Weber fractions in the first year, it was associated with mean reaction times in the non-symbolic numerical comparison task in the second year. These associations were not found to be discontinuous and could not be explained by individual differences in reasoning, processing speed, or inhibitory control. The present study extends previous findings by demonstrating that addition performance is associated with different markers of the ANS in the course of development.

14.
Front Psychol ; 4: 544, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23970877

RESUMEN

Different lines of evidence suggest that children's mental representations of numbers are spatially organized in form of a mental number line. It is, however, still unclear whether a spatial organization is specific for the numerical domain or also applies to other ordinal sequences in children. In the present study, children (n = 129) aged 8-9 years were asked to indicate the midpoint of lines flanked by task-irrelevant digits or letters. We found that the localization of the midpoint was systematically biased toward the larger digit. A similar, but less pronounced, effect was detected for letters with spatial biases toward the letter succeeding in the alphabet. Instead of assuming domain-specific forms of spatial representations, we suggest that ordinal information expressing relations between different items of a sequence might be spatially coded in children, whereby numbers seem to convey this kind of information in the most salient way.

15.
Cell Tissue Res ; 352(3): 469-78, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23584706

RESUMEN

Several studies have demonstrated a link between diabetes and the dysfunction of the inner ear. Few studies, however, have reported the signalling mechanisms involved in metabolic control in human inner ear cells. Knowledge of the expression and role of the insulin receptor and downstream signalling components in the inner ear is sparce. Our immunohistochemistry approach has shown that the insulin receptor, insulin receptor substrate 1 (IRS1), protein kinase B (PKB) and insulin-sensitive glucose transporter (GLUT4) are expressed in the sensory epithelium of the human saccule, which also exhibits expression of a calcium-sensitive cAMP/cGMP phosphodiesterase 1C (PDE1C) and the vasopressin type 2 receptor. IRS1 and PDE1C are selectively expressed in sensory epithelial hair cells, whereas the other components are expressed in sensory epithelial supporting cells or in both cell types, as judged from co-expression or non-co-expression with glial fibrillary acidic protein, a marker for supporting cells. Furthermore, IRS1 appears to be localized in association with sensory nerves, whereas GLUT4 is expressed in the peri-nuclear area of stromal cells, as is the case for aquaporin 2. Thus, the insulin receptor, insulin signalling components and selected cAMP signalling components are expressed in the human saccule. In addition to well-known mechanisms of diabetes complications, such as neuropathy and vascular lesions, the expression of these proteins in the saccule could have a role in the observed link between diabetes and balance/hearing disorders.


Asunto(s)
Epitelio/metabolismo , Insulina/metabolismo , Sáculo y Utrículo/metabolismo , Sensación , Transducción de Señal , Acuaporina 2/metabolismo , Fosfodiesterasas de Nucleótidos Cíclicos Tipo 1/metabolismo , Transportador de Glucosa de Tipo 4/metabolismo , Células Ciliadas Auditivas/citología , Células Ciliadas Auditivas/enzimología , Humanos , Proteínas Sustrato del Receptor de Insulina/metabolismo , Modelos Biológicos , Proteínas Proto-Oncogénicas c-akt/metabolismo , Receptor de Insulina/metabolismo , Receptores de Vasopresinas/metabolismo , Sáculo y Utrículo/citología , Células del Estroma/citología , Células del Estroma/metabolismo
16.
Nat Genet ; 45(3): 262-8, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23354437

RESUMEN

Primary ciliary dyskinesia (PCD) is characterized by dysfunction of respiratory cilia and sperm flagella and random determination of visceral asymmetry. Here, we identify the DRC1 subunit of the nexin-dynein regulatory complex (N-DRC), an axonemal structure critical for the regulation of dynein motors, and show that mutations in the gene encoding DRC1, CCDC164, are involved in PCD pathogenesis. Loss-of-function mutations disrupting DRC1 result in severe defects in assembly of the N-DRC structure and defective ciliary movement in Chlamydomonas reinhardtii and humans. Our results highlight a role for N-DRC integrity in regulating ciliary beating and provide the first direct evidence that mutations in DRC genes cause human disease.


Asunto(s)
Proteínas Algáceas/genética , Proteínas Portadoras/genética , Chlamydomonas , Cilios , Trastornos de la Motilidad Ciliar , Síndrome de Kartagener , Proteínas Asociadas a Microtúbulos/genética , Secuencia de Aminoácidos , Dineínas Axonemales/genética , Dineínas Axonemales/metabolismo , Dineínas Axonemales/ultraestructura , Axonema/genética , Axonema/metabolismo , Axonema/ultraestructura , Chlamydomonas/genética , Chlamydomonas/metabolismo , Chlamydomonas/ultraestructura , Cilios/genética , Cilios/metabolismo , Cilios/ultraestructura , Trastornos de la Motilidad Ciliar/genética , Trastornos de la Motilidad Ciliar/patología , Citoesqueleto/genética , Citoesqueleto/metabolismo , Humanos , Síndrome de Kartagener/genética , Síndrome de Kartagener/metabolismo , Síndrome de Kartagener/fisiopatología , Masculino , Proteínas Asociadas a Microtúbulos/metabolismo , Datos de Secuencia Molecular , Mutación , Inhibidor 1 de Activador Plasminogénico/genética , Inhibidor 1 de Activador Plasminogénico/metabolismo , Cola del Espermatozoide/metabolismo , Cola del Espermatozoide/ultraestructura
17.
PLoS One ; 7(8): e43122, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22916214

RESUMEN

The neural correlates of developmental dyslexia have been investigated intensively over the last two decades and reliable evidence for a dysfunction of left-hemispheric reading systems in dyslexic readers has been found in functional neuroimaging studies. In addition, structural imaging studies using voxel-based morphometry (VBM) demonstrated grey matter reductions in dyslexics in several brain regions. To objectively assess the consistency of these findings, we performed activation likelihood estimation (ALE) meta-analysis on nine published VBM studies reporting 62 foci of grey matter reduction in dyslexic readers. We found six significant clusters of convergence in bilateral temporo-parietal and left occipito-temporal cortical regions and in the cerebellum bilaterally. To identify possible overlaps between structural and functional deviations in dyslexic readers, we conducted additional ALE meta-analyses of imaging studies reporting functional underactivations (125 foci from 24 studies) or overactivations (95 foci from 11 studies ) in dyslexics. Subsequent conjunction analyses revealed overlaps between the results of the VBM meta-analysis and the meta-analysis of functional underactivations in the fusiform and supramarginal gyri of the left hemisphere. An overlap between VBM results and the meta-analysis of functional overactivations was found in the left cerebellum. The results of our study provide evidence for consistent grey matter variations bilaterally in the dyslexic brain and substantial overlap of these structural variations with functional abnormalities in left hemispheric regions.


Asunto(s)
Encéfalo/patología , Dislexia/patología , Humanos , Funciones de Verosimilitud
18.
Ann Otol Rhinol Laryngol ; 121(4): 217-23, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22606924

RESUMEN

OBJECTIVES: We evaluated a method for gas monitoring in the mastoid cavity using tunable diode laser spectroscopy by comparing it to simultaneously obtained computed tomographic (CT) scans. METHODS: The presented optical technique measures free gases, oxygen (O2), and water vapor (H2O) within human tissue by use of low-power diode lasers. Laser light was sent into the tip of the mastoid process, and the emerging light at the level of the antrum was captured with a detector placed on the skin. The absorption of H2O was used to monitor the probed gas volume of the mastoid cavity, and it was compared to the CT scan-measured volume. The ratio between O2 absorption and H2O absorption estimated the O2 content in the mastoid cavity and thus the ventilation. The parameters were compared to the grading of mastoid cavities based on the CT scans (n = 31). The reproducibility of the technique was investigated by measuring each mastoid cavity 4 times. RESULTS: Both O2 and H2O were detected with good reproducibility. The H2O absorption and the CT volume correlated (r = 0.69). The average ratio between the normalized O2 absorption and the H2O absorption signals was 0.7, indicating a lower O2 content than in surrounding air (expected ratio, 1.0), which is consistent with previous findings made by invasive techniques. All mastoid cavities with radiologic signs of disease were detected. CONCLUSIONS: Laser spectroscopy monitoring appears to be a usable tool for noninvasive investigations of gas composition in the mastoid cavity, providing important clinical information regarding size and ventilation.


Asunto(s)
Láseres de Semiconductores , Apófisis Mastoides/metabolismo , Análisis Espectral , Humanos , Oxígeno/análisis , Reproducibilidad de los Resultados , Tomografía Computarizada por Rayos X , Agua/análisis
19.
Front Neurol ; 2: 48, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21886636

RESUMEN

OBJECTIVE: To locate components and target proteins of relevance for the cAMP and cGMP signaling networks including cAMP and cGMP phosphodiesterases (PDEs), salt-inducible kinases (SIKs), subunits of Na+, K+-ATPases, and aquaporins (AQPs) in the human saccule. METHODS: The human saccule was dissected out during the removal of vestibular schwannoma via the translabyrinthine approach and immediately fixed. Immunohistochemistry was performed using PDE, SIK, Na(+), K(+)-ATPase, and AQP antibodies. RESULTS: PDEs selective for cAMP (PDE4A, PDE4D, and PDE8A) and cGMP (PDE9A) as well a dual specificity PDE (PDE10A) were detected in the sensory epithelium of the saccule. Furthermore, AQP2, 4, and 9, SIK1 and the α-1 subunit of the Na(+), K(+)-ATPase were detected. CONCLUSION: cAMP and cGMP are important regulators of ion and water homeostasis in the inner ear. The identification of PDEs and SIK1 in the vestibular system offers new treatment targets for endolymphatic hydrops. Exactly how the PDEs are connected to SIK1 and the SIK1 substrate Na(+), K(+)-ATPase and to AQPs 2, 4, 9 remains to be elucidated. The dissection of the signaling networks utilizing these components and evaluating their roles will add new basic knowledge regarding inner ear physiology.

20.
Ann N Y Acad Sci ; 1164: 257-62, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-19645909

RESUMEN

A sudden unilateral loss or impairment of vestibular function causes vertigo, dizziness, and impaired postural function. In most occasions, everyday activities supported or not by vestibular rehabilitation programs will promote a compensation and the symptoms subside. As the compensatory process requires sensory input, matching performed motor activity, both motor learning of exercises and matching to sensory input are required. If there is a simultaneous cerebellar lesion caused by the tumor or the surgery of the posterior cranial fossa, there may be a risk of a combined vestibulocerebellar lesion, with reduced compensatory abilities and with prolonged or sometimes permanent disability. On the other hand, a slow gradual loss of unilateral function occurring as the subject continues well-learned everyday activities may go without any prominent symptoms. A pretreatment plan was therefore implemented before planned vestibular lesions, that is, "PREHAB." This was first done in subjects undergoing gentamicin treatment for morbus Ménière. Subjects would perform vestibular exercises for 14 days before the first gentamicin installation, and then continue doing so until free of symptoms. Most subjects would only experience slight dizziness while losing vestibular function. The approach--which is reported here--was then expanded to patients with pontine-angle tumors requiring surgery, but with remaining vestibular function to ease postoperative symptoms and reduce risk of combined cerebellovestibular lesions. Twelve patients were treated with PREHAB and had gentamicin installations transtympanically. In all cases there was a caloric loss, loss of VOR in head impulse tests, and impaired subjective vertical and horizontal. Spontaneous, positional nystagmus, subjective symptoms, and postural function were normalized before surgery and postoperative recovery was swift. Pretreatment training with vestibular exercises continued during the successive loss of vestibular function during gentamicin treatment, and pre-op gentamicin ablation of vestibular function offers a possibility to reduce malaise and speed up recovery.


Asunto(s)
Enfermedades Vestibulares/fisiopatología , Vestíbulo del Laberinto/fisiología , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedades Vestibulares/rehabilitación
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