Piotr Świdziński

VEP latency and some properties of simple motor reaction-time distribution

SummaryThe median of simple motor reaction (RT) to a flash parallels the latencies of visually evoked potential (VEP) deflections if flash intensity is varied. However, mean and median reaction times are not equal because of the skewness of RT distribution. It therefore seemed plausible that the mean reaction time — intensity relationship would be steeper than that for VEP latency. Such divergence would account for the intensity-dependent motor component of RT revealed by other psychophysical studies. The latencies of VEP deflections were measured as a function of intensity and the results were compared with mean and median RTs. The difference between mean and median RT is constant and independent of flash intensity. Moreover, both values are parallel to VEP latency. The general pattern of results remains the same after a change in the distribution from which the foreperiod is sampled.

Assessing Auditory Processing Disorders in Children with Developmental Dyslexia Using Auditory Cognitive Event-Related Potentials

Objectives: It has been suggested that dyslexia is linked to a core cognitive deficit in phonological awareness tasks and/or in the processing of auditory stimuli. Auditory evoked potentials are a valid, objective measure of the accuracy of central auditory processing in humans. The aim of this study was to assess auditory evoked potentials in children with dyslexia. Patients and Methods: Sixty-six children participated in the study. A set of hearing tests and the recording of complex event-related potentials (ERPs) were performed. Results: Mixmatch negativity (MMN) and P300 waves were significantly more frequent in the healthy children (control group) than in children with dyslexia. The P300 wave was present in all subjects from the control group, the MMN wave in 92% of them. In the dyslexic group, complex ERPs were recorded roughly 33% of the time. Latencies of complex ERPs in children with dyslexia were greater than latencies in children in the control group. MMN and P300 maturation (change with age) was observed only for the control group. A wide range of MMN and P300 responses was observed across children with dyslexia. Conclusion: Complex ERPs may be useful in determining the condition of audiologic functions; however, on their own they are not sufficient to recognize dyslexia because of the heterogeneity of nonspecific changes.

Metody badania czynności fonacyjnej krtani w Klinice Otolaryngologicznej Uniwersytetu Poznańskiego w latach 1922–1939

Summary Introduction Indirect laryngoscopy development and progress initiated in 1854 by the autolaryngoscopy of the famous singing voice teacher Manuel Garcia in ENT speciality is connected with the names of L. Tuerck and J.N. Czermak, the last one being called the father of laryngoscopy. In 1878 M. Oertel used for the first time stroboscopic light in indirect laryngoscopy. The perception of stroboscopic picture is based on the Talbot principle. Object of the paper Two apparatuses used for the evaluation of larynx function in the Poznan ENT Department before the II World War are presented: – Polylaryngoscop enabling evaluation the indirect laryngoscopy simultaneously by several individuals. – Mechanical stroboscop of Oertel type with perforated disc moved by electrical engine. Conclusion For 130 years laryngostroboscopy belongs to the basic examination methods of larynx phonatory function.

Zaburzenia głosu mutacyjnego uwarunkowane czynnikami psychicznymi

Summary The case of 17 year old boy with mutational falsetto conditioned by a complex of psychic factors particulary with personality disorders and strong emotional bond with his mother was described. Phonation exercises lowered the average voice pitch. The stable results of phoniatric rehabilitation is dependent on effectiveness of psychological therapy of the whole family. Acoustic voice analysis demonstrates objectively the results of rehabilitation.The case of 17 year old boy with mutational falsetto conditioned by a complex of psychic factors particulary with personality disorders and strong emotional bond with his mother was described. Phonation exercises lowered the average voice pitch. The stable results of phoniatric rehabilitation is dependent on effectiveness of psychological therapy of the whole family. Acoustic voice analysis demonstrates objectively the results of rehabilitation.

Charakterystyka percepcyjno-akustyczna głosu i mowy po laryngektomiach nadpierścieniowych z CHP lub CHEP

INTRODUCTION Supracricoid laryngectomy with cricohyopexy (CHP) and cricoepiglottopexy (CHEP) are the one of functional laryngectomy. AIM The aim of the study is phonation assessment of the reconstruction larynx. Material and methods. The examined group consisted of 58 patients (49 males and 9 female). An average age 54. 32 patients underwent CHP and 26-CHEP CHP was performed in following modes: a) 1 arytenoid cartilage left in 17 cases, b) 2 arytenoid cartilages left in 14 cases and c) 1 arytenoid cartilage left and second was resected with subsequent reconstruction in 1 case. The arytenoid cartilage was reconstructed in 19 cases (8 after CHP and 11 after CHEP). The vascularized thyroid lobe was used to the reconstruction of arytenoid cartilage in 8 cases (6 after CHP and 2 after CHEP), cuneiform or corniculate cartilage was used in 4 patients (1 CHP and 3 CHEP) and mucous membrane in 7 cases (1 CHP and 6 CHEP). RESULT Socially efficient speech was found in 74% patients and the results were better after CHEP. CONCLUSION The phonetic-acoustic structure of voice and resonant speech was considerably different from the phonetic-acoustic structure of voice and speech under physiologic conditions. These differences applied to segmental (formant structure, frequencies, noise range), as well as suprasegmental voice features.Summary Introduction Supracricoid laryngectomy with cricohyopexy (CHP) and cricoepiglottopexy (CHEP) are the one of functional laryngectomy. Aim The aim of the study is phonation assessment of the reconstruction larynx. Material and methods The examined group consisted of 58 patients (49 males and 9 female). An average age 54. 32 patients underwent CHP and 26 – CHEP. CHP was performed in following modes: a) 1 arytenoid cartilage left in 17 cases, b) 2 arytenoid cartilages left in 14 cases and c) 1 arytenoid cartilage left and second was resected with subsequent reconstruction in 1 case. The arytenoid cartilage was reconstructed in 19 cases (8 after CHP and 11 after CHEP). The vascularized thyroid lobe was used to the reconstruction of arytenoid cartilage in 8 cases (6 after CHP and 2 after CHEP), cuneiform or corniculate cartilage was used in 4 patients (1 CHP and 3 CHEP) and mucous membrane in 7 cases (1 CHP and 6 CHEP). Result Socially efficient speech was found in 74% patients and the results were better after CHEP. Conclusion The phonetic-acoustic structure of voice and resonant speech was considerably different from the phonetic-acoustic structure of voice and speech under physiologic conditions. These differences applied to segmental (formant structure, frequencies, noise range), as well as suprasegmental voice features.

Hypothyroidism Affects Olfactory Evoked Potentials

Background. Objective electrophysiological methods for investigations of the organ of smell consist in recordings of olfactory cortex responses to specific, time restricted odor stimuli. In hypothyroidism have impaired sense of smell. Material and Methods. Two groups: control of 31 healthy subjects and study group of 21 with hypothyroidism. The inclusion criterion for the study group was the TSH range from 3.54 to 110 μIU/mL. Aim. Assessment of the latency time of evoked responses from the olfactory nerve N1 and the trigeminal nerve N5 using two smells of mint and anise in hypothyroidism. Results. The smell perception in subjective olfactory tests was normal in 85% of the hypothyroid group. Differences were noticed in the objective tests. The detailed intergroup analysis of latency times of recorded cortical responses P N5 and P N1 performed by means between the groups of patients with overt clinical hypothyroidism versus subclinical hypothyroidism demonstrated a significant difference (p < 0.05) whereas no such differences were found between the control group versus subclinical hypothyroidism group (p > 0.05). Conclusion. We can conclude that registration of cortex potentials at irritation of olfactory and trigeminal nerves offers possibilities for using this method as an objective indicator of hypothyroidism severity and prognostic process factor.

Usefulness of low redundancy speech tests with dyslexic children

Abstract Objectives: Developmental dyslexia in children can affect auditory and linguistic skills. Due to the impairment of hearing discrimination, attention, memory and perception, dyslexia causes the inability to process and interpret linguistic and verbal information effectively. Standard audiological examination is much less useful than low redundancy speech tests and electro-physiological examination, which are the only objective measures of central auditory processing. The aim of the study was to assess the usefulness of low redundancy speech tests and dichotic tests in the diagnosis of developmental dyslexia in children. Methods: Ten children aged 7–15 years were tested by a dichotic numeral test, a dichotic verbal minimal-pair test, and a Calearo test. Results: The experiments demonstrated that the dyslectic group achieved worse results in the above tests compared to the control group. This suggests information exchange disorders between the hemispheres, a lack of synchronization of acoustic perception in dichotic tests, and damage of the structures responsible for central auditory processing in the dominating hemisphere. Conclusions: The results of our study confirm the existence of information exchange disorders between the hemispheres and the lack of synchronization of acoustic perception in dichotic tests, where the signal is presented to both ears simultaneously. Much worse results in low redundancy tests reveal, moreover, damage of the structures responsible for central auditory processing in the dominating hemisphere. Altogether, this research has proved the usefulness of the conducted tests in the diagnostics of central auditory processing disorders in patients with dyslexia.

Dalsze badania nad testami mowy utrudnionej

INTRODUCTION The purpose of speech audiometry is to extend the diagnostics of central auditory processes. First audiometric tests were monaural tests introduced in the fifties by Bocca and Calearo to diagnose Central Auditory Processing Disorders (CAPD). Monaural tests are characterized by low redundancy, which allows for deciphering a given word or phrase only if the amount of accessible information exceeds a required minimum. Until now, a new monaural filtered speech test has been drawn up at the Department of Phoniatrics and Audiology. The purpose of the research was to draw up and assess the effectiveness of monaural low redundancy tests, in which the acoustic signal has been compressed or noise has been added. MATERIALS AND METHOD 35 people with normal hearing, aged 16-60, have been examined. The test material included: a compressed speech test, in which the speech signal has been accelerated by 25% with the use of Cool Edit Pro 2.0; the pauses between the words have not been shortened a speech-in-noise test, in which the noise has been added with the use of Cool Edit Pro 2.0. The signal/noise ratio has been set at the level of 10 dB. The examination has been conducted at three different volume levels: 25, 35 and 45 dB. CONCLUSIONS Best results have been achieved at the volume level of 45 dB (above hearing threshold); There were differences in results at volume levels 25 dB and 35 dB in compressed speech test and at volume level 25 dB in speech in noise. Both tests have shown the influence of age on the test result which suggests undiagnosed CAPD among people (with normal hearing) aged over 55.Summary Introduction The purpose of speech audiometry is to extend the diagnostics of central auditory processes. First audiometric tests were monaural tests introduced in the fifties by Bocca and Calearo to diagnose Central Auditory Processing Disorders (CAPD). Monaural tests are characterized by low redundancy, which allows for deciphering a given word or phrase only if the amount of accessible information exceeds a required minimum. Until now, a new monaural filtered speech test has been drawn up at the Department of Phoniatrics and Audiology. The purpose of the research was to draw up and assess the effectiveness of monaural low redundancy tests, in which the acoustic signal has been compressed or noise has been added. Materials and method 35 people with normal hearing, aged 16–60, have been examined. The test material included: a compressed speech test, in which the speech signal has been accelerated by 25% with the use of Cool Edit Pro 2.0; the pauses between the words have not been shortened a speech-in-noise test, in which the noise has been added with the use of Cool Edit Pro 2.0. The signal/noise ratio has been set at the level of 10 dB. The examination has been conducted at three different volume levels: 25, 35 and 45 dB. Conclusions Best results have been achieved at the volume level of 45 dB (above hearing threshold); There were differences in results at volume levels 25 dB and 35 dB in compressed speech test and at volume level 25 dB in speech in noise. Both tests have shown the influence of age on the test result which suggests undiagnosed CAPD among people (with normal hearing) aged over 55.