A utilização do mascaramento contralateral durante a pesquisa do potencial evocado auditivo de tronco encefálico é uma temática bastante discutida, visto a inexistência de um consenso na literatura acerca de sua necessidade. O objetivo deste estudo foi verificar a necessidade do uso do mascaramento contralateral no potencial evocado auditivo de tronco encefálico com estímulo tone burst apresentado com fone de inserção 3A e propor a aplicabilidade do ruído mascarador white noise na perda auditiva sensorioneural unilateral de graus severo ou profundo. Foram avaliados 15 indivíduos, de ambos os sexos, com o diagnóstico audiológico prévio de perda auditiva sensorioneural unilateral de graus severo ou profundo, com idades entre 2 a 40 anos. Para tanto, foi pesquisada a resposta neural definida pela presença da onda V na orelha com perda auditiva, nas frequências de 500, 1000, 2000 e 4000 Hz. Nos casos em que houve o registro, a pesquisa foi repetida com mascaramento white noise na orelha contralateral. Os registros foram analisados por dois juízes experientes em eletrofisiologia, a fim de verificar a concordância entre as análises. O Coeficiente Kappa (1,00) apresentou força de concordância quase perfeita e o de Correlação Intraclasse (1,00) foi excelente, entre as duas avaliadoras, em todas as análises. Como resultado, foi observada a audição cruzada, ao menos uma vez, em todas as frequências analisadas. Os níveis de mascaramento contralateral mínimos necessários para eliminar a participação da orelha não testada variaram de 10 a 20 dBnNA acima do limiar eletrofisiológico da orelha sem perda auditiva. Não foi possível realizar a análise para a frequência de 500 Hz devido à presença de artefato e ruído elétricos. Conclui-se que o uso do mascaramento contralateral no potencial evocado auditivo de tronco encefálico com estímulo tone burst apresentado com fone de inserção 3A é necessário nas frequências de 1000, 2000 e 4000 Hz em indivíduos com perda auditiva sensorioneural unilateral de graus severo ou profundo, nas intensidades de 15, 20 e 10 dB acima dos limiares eletrofisiológicos, respectivamente. / The use of contralateral masking on the investigation of auditory brainstem response is a topic widely discussed, however there is no consensus in literature about its necessity. The aim of this study was to verify the need of using masking in auditory brainstem response with tone burst stimulus presented with 3A insert earphones and to propose the applicability of white noise masking in severe or profound unilateral sensorineural hearing loss. Fifteen individuals of both genders with previous audiological diagnosis of severe or profound unilateral sensorineural hearing loss, aged between 2 to 40 years, were evaluated. For this, the neural response, which is defined by the presence of the V wave in the ear with hearing loss, was investigated in frequencies of 500, 1000, 2000 and 4000 Hz. In cases where there was a record, the search was repeated using white noise masking in the contralateral ear. The records were analyzed by two judges experienced in electrophysiology, in order to verify the concordance between the analyses. The Kappa coefficient (1.00) had almost perfect agreement strength and the Intraclass Correlation (1.00) was excellent between the two evaluators in all analyses. As a result, cross-audition was observed at least once in all analyzed frequencies. The minimum contralateral masking levels required to eliminate the untested ear involvement varied from 10 to 20 dBnNA above the electrophysiological threshold of the ear without hearing loss. It was not possible to perform the analysis for the frequency of 500 Hz due to the presence of electrical artifact and noise. It is concluded that the use of contralateral masking in the auditory brainstem response with tone burst stimulus presented with 3A insert earphone is necessary in frequencies of 1000, 2000 and 4000 Hz in individuals with severe or profound unilateral sensorineural hearing loss in intensities of 15, 20 and 10 dB above the electrophysiological thresholds, respectively.

Le vieillissement et la maladie d’Alzheimer (MA) sont caractérisés par des difficultés mnésiques associées à leurs altérations sensorielles et perceptives. Ces liens s’expliqueraient naturellement par les approches incarnées de la cognition qui définissent les connaissances comme ancrées dans leurs propriétés modales (sensori-motrices). Afin de tester ces approches incarnées, deux séries d’expériences ont été conduites auprès de jeunes adultes, personnes âgées saines et patient MA. Ces expériences combinaient une batterie complète de tests neuropsychologiques et un paradigme d’amorçage intersensoriel (audition vers vision). L’originalité fut l’ajout, pour la moitié des amorces auditives, d’un masque visuel sans signification. L’Expérience 1 était constituée deux phases distinctes, alors que dans l’Expérience 2, l’amorce et la cible étaient présentées dans un même essai. Les résultats démontrent un effet d’amorçage intersensoriel pour les jeunes adultes et les personnes âgées. Le masque a interféré avec cet effet d’amorçage, mais uniquement lorsque l’amorce et la cible correspondent à une même connaissance. Cette interférence et sa spécificité démontrent que les jeunes adultes comme les personnes âgées auraient des connaissances modales. En revanche, les patients MA ne présentent pas d’effet d’amorçage alors que celui-ci est de nature perceptive. Ces résultats supportent l’idée d’une déconnexion cérébrale dans la MA. L’ensemble des données permet de supposer que les difficultés mnésiques dans le vieillissement s’expliqueraient essentiellement par une dégradation de la qualité de leurs connaissances en lien avec leur perception. Les troubles mnésiques dans la MA proviendraient quant à eux d’un déficit d’intégration dynamique des différentes composantes des connaissances. Ces approches placent les interactions entre mémoire et perception au cœur du fonctionnement mnésique. / Normal aging as Alzheimer’s disease (AD) are characterized by memory disorders associated with the sensory and perceptive decline. These links may be easily explained in the embodied cognition theory, because in this one, knowledge remains grounded in its properties (mainly sensory-motor). The objective of the present research is to assess the embodied cognition theory applied to young adults, healthy elderly and patient with AD. In two experiments, a complete neuropsychological battery was associated with a cross-modal priming paradigm (audition to vision). The novelty of the paradigm was to present a visual meaningless mask for half of the sound primes. Experiment 1 was composed of two distinct phases, whereas the prime and the target were presented in the same trial in Experiment 2. The results demonstrated a significant cross-modal priming effect in young and healthy elderly adults. The mask has interfered with the priming effect only in the semantic congruent situations. The mask interference and its specificity demonstrate that young and elderly adults have modal knowledge. Reversely, the patients with AD did not show any priming effect while the effect is perceptual. This result supports the cerebral disconnection hypothesis in AD. The data taken together suggest that memory disorders in normal aging could be related to a degradation of the quality of their perception and thus of knowledge. Memory impairments in AD might come from an integration disorder to dynamically bind the different components of a memory. The present research support the embodied cognition theory and demonstrates the interest of this kind of approach to explore memory functioning in neuropsychology, such as in aging. These approaches put on the foreground the interactions between memory and perception.

Os peixes são organismos plásticos em relação às alterações de ciclos ambientais como o ciclo claro/escuro e ciclo de disponibildade alimentar, zeitgebers comprovadamente fortes para outros organismos vertebrados. O objetivo geral deste estudo foi verificar se o ciclo claro /escuro (CE) e o ciclo de disponibilidade alimentar (AJ) promovem sincronização da atividade locomotora em exemplares de robalos juvenis das espécies Centropomus parallelus e C. undecimalis coletados na região do Sistema Cananéia-Iguape (SP). Foi verificada uma possível relação hierárquica entre estes ciclos ambientais, e também foram observadas diferenças inter e intraindividuais de sincronização. Depois de coletados os peixes permaneceram em aquários do Laboratório de Ritmos Biológicos do GMDRB (Grupo Multidisciplinar de Desenvolvimento e Ritmos Biológicos) com temperatura da água entre 25 e 30oC, salinidade entre 20 a 30‰ e ciclos claro/escuro de 11:13h e 13:11h. A alimentação foi administrada manualmente, a intensidade luminosa da fase clara foi de 90lux e da fase escura foi de 10lux. A atividade locomotora dos peixes foi registrada individualmente através das interrupções nos feixes de luz infra-vermelha. Os feixes foram gerados por emissores de luz e detectados por fotocélulas; os pares emissor-fotocélula foram distribuídos na superfície e fundo dos aquários. A interrupção foi convertida em pulso elétrico por uma interface digital. Os dados foram processados através do programa “El Temps”(Diez-Noguera, 1999); foram confeccionados actogramas, periodogramas de Lomb-Scargle e plexogramas. Foram calculadas as porcentagens de alocação da atividade locomotora em cada fase (claro, escuro, jejum e alimentação) baseadas no número total de horas da fase correspondente. As porcentagens foram então comparadas em todas as condições experimentais, para todos os indivíduos. As comparações foram feitas através do teste Z com correção de Yates, com o auxílio do programa estatístico “SigmaStat” versão 3.11. Diante dos resultados obtidos pôde-se concluir que somente o ciclo claro /escuro foi capaz de sincronizar alguns dos exemplares testados neste estudo. O mascaramento promovido por este ciclo ambiental possivelmente é responsável pela plasticidade temporal e reflete a complexidade do ambiente costeiro repleto de ciclos ambientais. / Fish are generally adaptable to changes in environmental cycles such as the light/dark cycle (LD) and food availability cycle (EF). These cycles are the most common and considered strong zeitgebers for vertebrates. The aim of this study was to investigate whether LD and EF cycles were able to synchronize the locomotor activity of juvenile snooks (Centropomus undecimalis and C. parallelus) collected at Cananéia estuary (São Paulo – Brazil). Juvenile fish were kept in a laboratory lightproof room (Laboratório de Ritmos Biológicos do GMDRB-Grupo Multidisciplinar de Desenvolvimento e Ritmos Biológicos), water temperature between 25 and 30oC, salinity between 20 and 30‰. Feeding was performed manually. A bulb of a blue light was located at the top of aquaria (90lx in the light phase and 10lx in the dark phase). Locomotor activity was detected by six (eight, depending on aquaria) pairs of infrared sensors distributed on the surface and at the bottom of aquaria. Data collected from the infrared sensors were analyzed through the program “El Temps”. Actograms, Lomb-Scargle periodograms, and plexograms were drawn. Locomotor activity percentages were calculated for the different phases of the cycles and compared in all experimental manipulations for all indivuduals. The comparisions were calculated using the software “SigmaStat” version 3.11 through the test Z with Yates correction. We concluded that the LD cycle syncronized (probably masking) the locomotor activity in some juvenile fish studied whereas the EF cycle did not. We discuss the temporal plasticity observed in the context of the complexity of coastal environmental.

Ringtones are a common distracting sound in modern workspaces. In an earlierexperiment, ringtones increasing in volume (looming) produced greater attentional capture effectin the context of serial short-term memory, than ringtones with sudden onsets that decreased involume (receding). To determine whether this effect occurred merely because the loudest part ofthe looming ringtone coincided with the most sensitive part of the serial short-term memory task,this study repeated the sound conditions of the first experiment, but altered their timing. In thisstudy, the onset of the ringtones were brought forward in time such that the loudest part of thelooming ringtone now coincided with the part of the serial short-term memory task wherein theonset of the looming ringtone occurred in the first experiment. The looming ringtone againproduced more disruption than the receding ringtone, which failed to disrupt performance relativeto the quiet control condition. The presence of a masking sound eliminated the looming ringtoneeffect, as in the previous study. The results here support previous work demonstrating that thelooming sounds give rise to attentional capture and that this reflects an evolutionary adaptation tounconsciously react to approaching sounds/objects.

Auditory filters were derived in 20 normal-hearing human listeners at center frequencies (CFs) of 913, 1095, 3651, and 4382 Hz using the roex (p,r) method. Comparisons were made between slopes of the filters' skirts at the neighboring CFs with filter output levels of 45 and 70 dB. The same comparisons were made with regard to filter equivalent rectangular bandwidth (ERB). In the 1000-Hz region, the low-frequency slopes (Pl) of filters centered at 913 and 1095 Hz were significantly correlated at both stimulus levels, while the high-frequency slopes (Pu) were similar only at the high test level. In the 4000-Hz region, for sinusoids of 3651 and 4382 Hz, the level effect was clearer as both Pu and Pl values diverged at the low level but were related at high levels. The ERBs centered at the same CFs displayed a similar level dependence. At the stimulus level most likely to be affected by an active feedback mechanism, auditory filters centered at nearly the same frequency displayed quite distinct frequency selectivity, and this trend was stronger in the 4000-Hz region than the 1000-Hz region. The findings suggest that a saturating, active cochlear mechanism may not be distributed evenly, or contribute to peripheral tuning with equal effectiveness throughout the length of the partition.

The recovery from prior stimulation of the compound action potential (CAP) was measured using a forward masking stimulus paradigm in four normal-hearing, human subjects. The CAP was recorded using a wick electrode placed on the tympanic membrane. The effects of a 4000-Hz, 97-dB SPL conditioning stimulus on CAP amplitude in response to a 4000-Hz probe were measured as a function of conditioner–probe interval for three probe levels. The normalized probe response amplitude was completely recovered to the control values at an average conditioner–probe interval of 1359 ms, similar to that observed in chinchilla (Relkin, E.M., Doucet, J.R., Sterns, A., 1995. Recovery of the compound action potential following prior stimulation: evidence for a slow component that reflects recovery of low spontaneous-rate auditory neurons, Hear. Res. 83, 183–189). The present results are interpreted as a consequence of the slow recovery of low spontaneous-rate (SR), high threshold neurons from prior stimulation (Relkin, E.M., Doucet, J.R., 1991. Recovery from prior stimulation. I: Relationship to spontaneous firing rates of primary auditory neurons. Hear. Res. 55, 215–222) and may provide indirect physiological evidence for the existence of a class of low-SR auditory neurons in humans.

ABSTRACT DECISION TREE CLASSIFICATION OF MULTI-TEMPORAL IMAGES FOR FIELD-BASED CROP MAPPING Sencan, Se&ccedil / il M. Sc., Department of Geodetic and Geographic Information Technologies Supervisor: Assist. Prof. Dr. Mustafa T&uuml / rker August 2004, 125 pages A decision tree (DT) classification approach was used to identify summer (August) crop types in an agricultural area near Karacabey (Bursa), Turkey from multi-temporal images. For the analysis, Landsat 7 ETM+ images acquired in May, July, and August 2000 were used. In addition to the original bands, NDVI, PCA, and Tasselled Cap Transformation bands were also generated and included in the classification procedure. Initially, the images were classified on a per-pixel basis using the multi-temporal masking technique together with the DT approach. Then, the classified outputs were applied a field-based analysis and the class labels of the fields were directly entered into the Geographical Information System (GIS) database. The results were compared with the classified outputs of the three dates of imagery generated using a traditional maximum likelihood (ML) algorithm. It was observed that the proposed approach provided significantly higher overall accuracies for the May and August images, for which the number of classes were low. In May and July, the DT approach produced the classification accuracies of 91.10% and 66.15% while the ML classifier produced 84.38% and 63.55%, respectively. However, in August nearly the similar overall accuracies were obtained for the ML (70.82%) and DT (69.14%) approaches. It was also observed that the use of additional bands for the proposed technique improved the separability of the sugar beet, tomato, pea, pepper, and rice classes.

Thesis (Au.D.)--James Madison University, 2010. / Includes bibliographical references.

Thesis (Au.D.)--James Madison University, 2010. / Includes bibliographical references.

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