Hodnotenie bádateľských zručností žiakov gymnázia

Bádateľsky orientované vzdelávanie (BOV) patrí v poslednom období k najčastejšie skloňovaným pojmom v súvislosti s inováciou prírodovedného vzdelávania. Cieľom BOV je okrem konceptuálneho porozumenia aj rozvoj žiackych zručností realizovať bádanie a vyhodnocovať jeho výsledky. Prezentovaný výskum je zameraný na diagnostikovanie aktuálnej úrovne rozvoja vybraných bádateľských zručností žiakov gymnázia. Vychádzajúc z dostupných testov bol na základe klasifikácie bádateľských zručností vytvorený test bádateľských zručností. Testové úlohy určené na posúdenie úrovne zručnosti plánovať postup experimentu (identifikovať premenné a ich vzťah), transformovať výsledky do grafu, určovať vzťahy medzi premennými, identifikovať možné zdroje chýb a obhajovať výsledky a argumentovať, sú vsadené do matematického, fyzikálneho alebo informatického kontextu. Test bol zodpovedaný vzorkou 751 žiakov 1. a 2. ročníka niekoľkých gymnázií na Slovensku. Kvantitatívna analýza výsledkov testovania ukázala nízku priemernú úspešnosť žiakov v celom teste (32,5 %) ako aj v jednotlivých testových úlohách pohybujúcu sa približne v rozmedzí 8–50 %. Zo štatistického testovania vyplynulo, že medzi výsledkami žiakov 1. a 2. ročníka nebol významný rozdiel, zatiaľ čo výsledky chlapcov boli lepšie ako výsledky dievčat. Podrobná kvalitatívna analýza odhalila mnohé nedostatky, ktoré sa najvýraznejšie prejavili v oblasti analýzy a interpretácie výsledkov a žiackych argumentačných zručností

Functional changes in the human auditory cortex in ageing.

Hearing loss, presbycusis, is one of the most common sensory declines in the ageing population. Presbycusis is characterised by a deterioration in the processing of temporal sound features as well as a decline in speech perception, thus indicating a possible central component. With the aim to explore the central component of presbycusis, we studied the function of the auditory cortex by functional MRI in two groups of elderly subjects (>65 years) and compared the results with young subjects (<lt;30 years). The elderly group with expressed presbycusis (EP) differed from the elderly group with mild presbycusis (MP) in hearing thresholds measured by pure tone audiometry, presence and amplitudes of transient otoacoustic emissions (TEOAE) and distortion-product oto-acoustic emissions (DPOAE), as well as in speech-understanding under noisy conditions. Acoustically evoked activity (pink noise centered around 350 Hz, 700 Hz, 1.5 kHz, 3 kHz, 8 kHz), recorded by BOLD fMRI from an area centered on Heschl's gyrus, was used to determine age-related changes at the level of the auditory cortex. The fMRI showed only minimal activation in response to the 8 kHz stimulation, despite the fact that all subjects heard the stimulus. Both elderly groups showed greater activation in response to acoustical stimuli in the temporal lobes in comparison with young subjects. In addition, activation in the right temporal lobe was more expressed than in the left temporal lobe in both elderly groups, whereas in the young control subjects (YC) leftward lateralization was present. No statistically significant differences in activation of the auditory cortex were found between the MP and EP groups. The greater extent of cortical activation in elderly subjects in comparison with young subjects, with an asymmetry towards the right side, may serve as a compensatory mechanism for the impaired processing of auditory information appearing as a consequence of ageing

Age-Related Differences in Hearing Function and Cochlear Morphology between Male and Female Fischer 344 Rats

Fischer 344 (F344) rats represent a strain that is frequently used as a model for fast aging. In this study, we systematically compare the hearing function during aging in male and female F344 rats, by recording auditory brainstem responses (ABRs) and distortion product otoacoustic emissions (DPOAEs). In addition to this, the functional parameters are correlated with the cochlear histology. The parameters of the hearing function were not different in the young (3-month-old) male and female F344 rats; the gender differences occurred only in adult and aged animals. In 8–24-month-old males, the ABR thresholds were higher and the ABR amplitudes were smaller than those measured in females of the same age. There were no gender differences in the neural adaptation tested by recording ABRs, elicited by a series of clicks with varying inter-click interval (ICI). Amplitudes of DPOAEs in both the males and females decreased with age, but in the males, the decrease of DPOAE amplitudes was faster. In males older than 20 months, the DPOAEs were practically absent, whereas in 20–24-month-old females, the DPOAEs were still measurable. There were no gender differences in the number of surviving outer hair cells (OHC) and the number of inner hair cell ribbon synapses in aged animals. The main difference was found in the stria vascularis (SV). Whereas the SV was well preserved in females up to the age of 24 months, in most of the age-matched males the SV was evidently deteriorated. The results demonstrate more pronounced age-related changes in the cochlear morphology, hearing thresholds, ABR amplitudes and DPOAE amplitudes in F344 males compared with females

Complications of Microsurgery of Vestibular Schwannoma

Background. The aim of this study was to analyze complications of vestibular schwannoma (VS) microsurgery. Material and Methods. A retrospective study was performed in 333 patients with unilateral vestibular schwannoma indicated for surgical treatment between January 1997 and December 2012. Postoperative complications were assessed immediately after VS surgery as well as during outpatient followup. Results. In all 333 patients microsurgical vestibular schwannoma (Koos grade 1: 12, grade 2: 34, grade 3: 62, and grade 4: 225) removal was performed. The main neurological complication was facial nerve dysfunction. The intermediate and poor function (HB III–VI) was observed in 124 cases (45%) immediately after surgery and in 104 cases (33%) on the last followup. We encountered disordered vestibular compensation in 13%, permanent trigeminal nerve dysfunction in 1%, and transient lower cranial nerves (IX–XI) deficit in 6%. Nonneurological complications included CSF leakage in 63% (lateral/medial variant: 99/1%), headache in 9%, and intracerebral hemorrhage in 5%. We did not encounter any case of meningitis. Conclusions. Our study demonstrates that despite the benefits of advanced high-tech equipment, refined microsurgical instruments, and highly developed neuroimaging technologies, there are still various and significant complications associated with vestibular schwannomas microsurgery

Stimulation scheme used for the recording of evoked activity for each separate frequency range during one single measurement.

<p>Each event of acoustic stimulation lasted 6 s and was followed by 3 scans (TR = 8s) without stimulation. The block shown here was repeated 10 times. Diagram shows the model used for statistical evaluation (HRF for single 6 s stimulus).</p

Speech discrimination score (SDS) in background babble noise.

<p>Level of babble noise was set at 65 and 70 dB. Average values with SEM, one way ANOVA, Tukey’s correction, * p<0.05.</p

Does Attempt at Hearing Preservation Microsurgery of Vestibular Schwannoma Affect Postoperative Tinnitus?

Background. The aim of this study was to analyze the effect of vestibular schwannoma microsurgery via the retrosigmoid-transmeatal approach with special reference to the postoperative tinnitus outcome. Material and Methods. A prospective study was performed in 89 consecutive patients with unilateral vestibular schwannoma indicated for microsurgery. Patient and tumor related parameters, pre- and postoperative hearing level, intraoperative findings, and hearing and tinnitus handicap inventory scores were analyzed. Results. Cochlear nerve integrity was achieved in 44% corresponding to preservation of preoperatively serviceable hearing in 47% and useful hearing in 21%. Main prognostic factors of hearing preservation were grade/size of tumor, preoperative hearing level, intraoperative neuromonitoring, tumor consistency, and adhesion to neurovascular structures. Microsurgery led to elimination of tinnitus in 66% but also new-onset of the symptom in 14% of cases. Preservation of useful hearing and neurectomy of the eighth cranial nerve were main prognostic factors of tinnitus elimination. Preservation of cochlear nerve but loss of preoperative hearing emerged as the main factor for tinnitus persistence and new onset tinnitus. Decrease of THI scores was observed postoperatively. Conclusions. Our results underscore the importance of proper pre- and intraoperative decision making about attempt at hearing preservation versus potential for tinnitus elimination/risk of new onset of tinnitus

A comparison of temporal lobe activation (difference maps (from temporal lobe) of group statistics) between MP vs. YC and EP vs. YC, shown as the difference in the amount of activated voxels (threshold set at p = 0.001 uncorrected).

<p>A comparison of temporal lobe activation (difference maps (from temporal lobe) of group statistics) between MP vs. YC and EP vs. YC, shown as the difference in the amount of activated voxels (threshold set at p = 0.001 uncorrected).</p

Averaged cortical activity evoked by acoustic stimulation examined by fMRI in all 3 groups.

<p>A—YC, b—MP, c—EP; group statistics, p = 0.05 with FWE correction; red—pink noise centered at 350 Hz and 700 Hz; blue—pink noise centered at 1.5 kHz, 3 kHz and 8 kHz. The arrowheads accentuate an increase in the right AC activation in both elderly groups.</p

Results of the pure tone audiometry in the extended high-frequency range in all three groups.

<p>Data shown as mean±SEM and medians (in case of no hearing sensation 110 dB was set as the threshold).</p