Search results for "Percept"
showing 10 items of 3839 documents
Speech perception performance as a function of stimulus pulse rate and processing strategy preference for the Cochlear™ Nucleus®CI24RE device: Relati…
2010
Current cochlear implants can operate at high pulse rates. The effect of increasing pulse rate on speech performance is not yet clear. Habituation to low rates may affect the outcome. This paper presents the results of three subsequent studies using different experimental paradigms, applying the Nucleus CI24RE device, and conducted by ten European implant teams. Pulse rate per channel varied from 500 to 3500 pulses per second with ACE and from 1200 to 3500 pps with CIS strategy. The results showed that the first rate presented had little effect on the finally preferred rate. Lower rates were preferred. The effect of pulse rate on word scores of post-linguistic implantees was small; high rat…
Blue-yellow deficiencies in young moderate smokers.
2021
Purpose To evaluate whether tobacco affects color vision in young moderate smokers. Methods Chromatic mechanisms of 13 moderate smokers (10–20 cigarettes/day and at least 5 years smoking) and 17 non-smokers in the 18–35 age range were assessed with the Farnsworth-Munsell 100-hue (FM100h) test and short wavelength automated perimetry (SWAP). Results FM100h Total Error Scores (TES) were higher for smokers, and although differences were not significant (p = 0.14), a linear model with principal component analysis was able to explain 95% of the variance in TES and red-green partial error scores, though not in blue-yellow partial error scores (p = 0.07), using the number of years as smokers and t…
Blocking by word frequency and neighborhood density in visual word recognition: A task-specific response criteria account
2004
International audience; Effects of blocking words by frequency class (high vs. low) and neighborhood density (high vs. low) were examined in two experiments using progressive demasking and lexical decision tasks. The aim was to examine the predictions of a task-specific response criteria account of list-blocking effects. Distinct patterns of blocking effects were obtained in the two tasks. In the progressive demasking task, a pure-list disadvantage was obtained to low frequency-high density words, whereas high frequency-low density produced a trend toward a pure-list advantage. In lexical decision, high-frequency words showed a pure-list advantage that was strongest in high-density words, w…
Perceiving musical tension in long chord sequences
1999
We attempted to predict perceived musical tension in longer chord sequences by hierarchic and sequential models based on Lerdahl and Jackendoff's and Lerdahl's cognitive theories and on Parncutt's sensory-psychoacoustical theory. Musicians and nonmusicians were asked to rate the perceived tension of chords which were drawn either from a piece composed for the study (Exp. 1) or from a Chopin Prelude (Exps. 2-4). In Exps. 3 and 4, several experimental manipulations were made to emphasize either the global or the local structure of the piece and to verify how these manipultions would affect the respective contribution of the models in the ratings. In all experiments, musical tension was only w…
Normative data on the familiarity and difficulty of 196 Spanish word fragments
2005
In this article, normative data on the familiarity and difficulty of 196 single-solution Spanish word fragments are presented. The database includes the following indices: difficulty, familiarity, frequency, number of meanings, number of letters given in the fragment, first and/or last letters given, and ratio of letters to blanks. A factor analysis was performed on difficulty, and two factors were obtained. Frequency, familiarity, and number of meanings loaded highly on the first factor, which we consider to measure lexical processes, whereas number of letters in the fragment, first and/or last letters given, and ratio of letters to blanks loaded highly on the second factor, which we judge…
Understanding metaphors and idioms: A single-case neuropsychological study in a person with Down syndrome
2001
The ability of subject F.F., diagnosed with Down syndrome, to appreciate nonliteral (interpreting metaphors and idioms) and literal (vocabulary knowledge, including highly specific and unusual items) aspects of language was investigated. F.F. was impaired in understanding both metaphors and idioms, while her phonological, syntactic and lexical–semantic skills were largely preserved. By contrast, some aspects of F.F.'s executive functions and many visuospatial abilities were defective. The suggestion is made that the interpretation of metaphors and idioms is largely independent of that of literal language, preserved in F.F., and that some executive aspects of working memory and visuospatial …
Changes in colour discrimination during the menstrual cycle.
2006
A group of normal women of reproductive age were recruited to investigate colour discrimination during the various phases of the menstrual cycle. Colour vision was tested with the Farnsworth-Munsell 100-hue arrangement test, and the test was administered at 3 time points: the beginning of the cycle, ovulation, and the end of the cycle. We found that colour discrimination was better at ovulation than at the other 2 time points. It is possible that psychological as well as hormonal factors could contribute to improved colour vision performance at ovulation.
Simulating Images Seen by Patients with Inhomogeneous Sensitivity Losses
2012
PURPOSE We aim to simulate how colored images are perceived by subjects with local achromatic and chromatic contrast sensitivity losses in the visual field (VF). METHODS The spatiochromatic corresponding pair algorithm, introduced in a previous article (J Opt Soc Am (A) 2004;21:176-186), has been implemented with a linear model of the visual system. Spatial information is processed separately by the chromatic and achromatic mechanisms by means of a multiscale model, with sensors selective to frequency, orientation, and spatial position, whose mechanism-dependent relative weights change with the spatial location of the image. These weights have been obtained from perimetric data from a patie…
Timing of right parietal and frontal cortex activity in visuo-spatial perception: A TMS study in normal individuals
2001
In a recent study we showed that repetitive transcranial magnetic stimulation (rTMS) with train duration of 400 ms over right frontal and right posterior parietal cortices gives rise to transitory contralateral visuo-spatial neglect in normal subjects. In the present experiment we investigated whether using single-pulse TMS it is possible to obtain information about the timing of cortical activity related to spatial cognition. Nine healthy subjects performed in baseline condition and during TMS a tachistoscopic task, requiring a forced-choice estimation of the length of the two segments of prebisected horizontal lines. Single-pulse TMS was triggered at various time intervals (150 ms, 225 ms…
Functional connectivity of major depression disorder using ongoing EEG during music perception
2020
Abstract Objective The functional connectivity (FC) of major depression disorder (MDD) has not been well studied under naturalistic and continuous stimuli conditions. In this study, we investigated the frequency-specific FC of MDD patients exposed to conditions of music perception using ongoing electroencephalogram (EEG). Methods First, we applied the phase lag index (PLI) method to calculate the connectivity matrices and graph theory-based methods to measure the topology of brain networks across different frequency bands. Then, classification methods were adopted to identify the most discriminate frequency band for the diagnosis of MDD. Results During music perception, MDD patients exhibit…