scholarly journals Shorter neural adaptation to sounds accounts for dyslexics’ abnormal perceptual and reading dynamics

2016 ◽  
Author(s):  
Sagi Jaffe-Dax ◽  
Orr Frenkel ◽  
Merav Ahissar
Keyword(s):  
Implicit Memory ◽  
Oral Reading ◽  
Frequency Discrimination ◽  
Neural Adaptation ◽  
Time Interval ◽  
Similar Time ◽  
Complex Stimuli ◽  
Temporal Intervals ◽  
Oral Reading Rate ◽  
Underlying Mechanisms

AbstractDyslexia is a prevalent reading disability whose underlying mechanisms are still disputed. We studied the neural mechanisms underlying dyslexia using a simple frequency-discrimination task. Though participants were asked to compare the 2-tones in each trial, implicit memory of previous trials affected their responses. We hypothesized that implicit memory decays faster among dyslexics. We tested this by increasing the temporal intervals between consecutive trials, and measuring the behavioral impact and ERP responses from the auditory cortex. Dyslexics showed a faster decay of implicit memory effects on both measures, with similar time constants. Finally, faster decay also characterized dyslexics’ benefits in oral reading rate. It decreased faster as a function of the time interval from the previous reading of the same non-word. We propose that dyslexics’ shorter neural adaptation paradoxically accounts for their longer reading times, since it induces noisier and less reliable predictions for both simple and complex stimuli.

scholarly journals Dyslexics’ faster decay of implicit memory for sounds and words is manifested in their shorter neural adaptation

eLife ◽  
2017 ◽  
Vol 6 ◽  
Author(s):  
Sagi Jaffe-Dax ◽  
Or Frenkel ◽  
Merav Ahissar
Keyword(s):  
Implicit Memory ◽  
Oral Reading ◽  
Frequency Discrimination ◽  
Neural Adaptation ◽  
Time Interval ◽  
Similar Time ◽  
Temporal Intervals ◽  
Oral Reading Rate ◽  
Underlying Mechanisms ◽  
The Impact

Dyslexia is a prevalent reading disability whose underlying mechanisms are still disputed. We studied the neural mechanisms underlying dyslexia using a simple frequency-discrimination task. Though participants were asked to compare the two tones in each trial, implicit memory of previous trials affected their responses. We hypothesized that implicit memory decays faster among dyslexics. We tested this by increasing the temporal intervals between consecutive trials, and by measuring the behavioral impact and ERP responses from the auditory cortex. Dyslexics showed a faster decay of implicit memory effects on both measures, with similar time constants. Finally, faster decay of implicit memory also characterized the impact of sound regularities in benefitting dyslexics' oral reading rate. Their benefit decreased faster as a function of the time interval from the previous reading of the same non-word. We propose that dyslexics’ shorter neural adaptation paradoxically accounts for their longer reading times, since it reduces their temporal window of integration of past stimuli, resulting in noisier and less reliable predictions for both simple and complex stimuli. Less reliable predictions limit their acquisition of reading expertise.

The Effect Of Auditory Masking Upon Oral Reading Rate

1958 ◽  
Vol 23 (3) ◽  
pp. 250-252 ◽  
Author(s):  
Richard A. Winchester ◽  
Edward W. Gibbons
Keyword(s):  
Oral Reading ◽  
Reading Rate ◽  
Auditory Masking ◽  
Oral Reading Rate

Development of muscarinic potassium current in fetal and neonatal rat heart

1997 ◽  
Vol 272 (3) ◽  
pp. H1188-H1195 ◽  
Author(s):  
M. Takano ◽  
A. Noma
Keyword(s):  
Time Course ◽  
Single Channel ◽  
Cell Voltage ◽  
Neonatal Rat ◽  
Receptor Subtypes ◽  
Similar Time ◽  
Adult Rat ◽  
Functional Development ◽  
K Current ◽  
Underlying Mechanisms

Single atrial myocytes were isolated from fetal, neonatal, and adult rat hearts. The muscarinic K+ current activated by rapid application of acetylcholine (ACh) and adenosine (Ado) was recorded under the whole cell voltage clamp. The current density (pA/pF) of ACh-induced K+ current increased from gestation day 12 to the maximum on neonatal day 20 and decreased in the adult myocytes due to greater increase of the membrane capacitance. The development of Ado-induced K+ current followed a similar time course except for a remarkable decrease after neonatal day 10. No significant change was found in single-channel properties during the development. Receptor subtypes were M2 and A1 receptors for ACh and Ado, respectively. In the dose-response relationship, the half-maximal concentration for ACh-induced current markedly decreased with age, from 1.44 (fetus) to 0.17 microM (adult), whereas that for Ado increased from 0.45 (fetus) to 0.99 microM (adult). These changes of the muscarinic K+ current were discussed in relation to the functional development of cardiac myocytes and underlying mechanisms.

scholarly journals Effects of oral reading rate and inflection on intraverbal responding

1989 ◽  
Vol 7 (1) ◽  
pp. 83-89 ◽  
Author(s):  
Henry A. Tenenbaum ◽  
William D. Wolking
Keyword(s):  
Oral Reading ◽  
Reading Rate ◽  
Oral Reading Rate

scholarly journals How many words do we read per minute? A review and meta-analysis of reading rate

2019 ◽  
Author(s):  
Marc Brysbaert
Keyword(s):  
Language Processing ◽  
Oral Reading ◽  
Meta Analysis ◽  
Silent Reading ◽  
Reading Rate ◽  
English As Second Language ◽  
Old Adults ◽  
Non Fiction ◽  
The Difference ◽  
Oral Reading Rate

Based on the analysis of 190 studies (18,573 participants), we estimate that the average silent reading rate for adults in English is 238 words per minute (wpm) for non-fiction and 260 wpm for fiction. The difference can be predicted by taking into account the length of the words, with longer words in non-fiction than in fiction. The estimates are lower than the numbers often cited in scientific and popular writings. The reasons for the overestimates are reviewed. The average oral reading rate (based on 77 studies and 5,965 participants) is 183 wpm. Reading rates are lower for children, old adults, and readers with English as second language. The reading rates are in line with maximum listening speed and do not require the assumption of reading-specific language processing. Within each group/task there are reliable individual differences, which are not yet fully understood. For silent reading of English non-fiction most adults fall in the range of 175 to 300 wpm; for fiction the range is 200 to 320 wpm. Reading rates in other languages can be predicted reasonably well by taking into account the number of words these languages require to convey the same message as in English.

scholarly journals A Temporal Model of Aural Frequency Discrimination

2021 ◽  
Author(s):  
◽  
Kaye McAulay
Keyword(s):  
Signal To Noise Ratio ◽  
Discrimination Performance ◽  
Frequency Discrimination ◽  
Signal To Noise ◽  
Low Frequencies ◽  
Human Data ◽  
Temporal Intervals ◽  
Temporal Model ◽  
Noise Ratio ◽  
Positive Axis

<p>The importance of temporal information versus place information in frequency analysis by the ear is a continuing controversy. This dissertation developes a temporal model which simulates human frequency discrimination. The model gives guantitative measures of performance for the discrimination of sinusoids in white gaussian noise. The model simulates human frequency discrimination performance as a function of frequency and signal-to-noise ratio. The model's predictions are based on the temporal intervals between the positive axis crossings of the stimulus. The histograms of these temporal intervals were used as the underlying distributions from which indices of discriminability were calculated. Human freguency discrimination data was obtained for five observers as a function of frequency and signal-to-noise ratio. The data were analysed using the method of Group-operating-characteristic (GOC) Analysis. This method of analysis statistically removes unique noise from data. The unique noise was removed by summing observers' ratings for identical stimuli. This method of analysis gave human frequency discrimination data with less unigue noise than any existing frequency data. The human data were used for evaluating the model. The GOC Analysis was also used to study the improvement in d' as a function of stimulus replications and signal-to-noise ratio. The model was a good fit to the human data at 250 Hz, for two signal-to-noise ratios. The model did not fit the data at 1000 Hz or 5000 Hz. There was some evidence of a transition occuring at 1000 Hz. This investigation supported the idea that human frequency discrimination relies on a temporal mechanism at low frequencies with a transition to some other mechanism at about lO00 Hz.</p>

scholarly journals Multivariate methods for testing hypotheses of temporal community dynamics

2018 ◽  
Author(s):  
Hannah L. Buckley ◽  
Nicola J. Day ◽  
Bradley S. Case ◽  
Gavin Lear ◽  
Aaron M. Ellison
Keyword(s):  
Community Dynamics ◽  
Temporal Change ◽  
Change Processes ◽  
Multivariate Methods ◽  
Quantitative Review ◽  
Biological Communities ◽  
Road Map ◽  
Temporal Intervals ◽  
Underlying Mechanisms ◽  
Extinction Events

ABSTRACTFor ecological research to make important contributions towards understanding and managing temporally-variable global change processes, such as responses to land-use and climatic change, we must have effective and comparable ways to quantify and analyse compositional change over time in biological communities. These changes are the sum of local colonisation and extinction events, or changes in the biomass and relative abundance of taxa within and among samples. We conducted a quantitative review of currently available methods for the analysis of multivariate datasets collected at temporal intervals. This review identified the need for the application of quantitative, hypothesis-based approaches to understand temporal change in community composition, particularly for small datasets with less than 15 temporal replicates. To address this gap, we: (1) conceptually present how temporal patterns in community dynamics can be framed as specific, testable hypotheses; (2) provide three fully-worked case-studies, complete with R code, demonstrating multivariate analysis methods for temporal hypothesis testing and pattern visualisation; and (3) present a road map for testing specific, quantitative hypotheses relating to the underlying mechanisms of temporal community dynamics.

scholarly journals Secondary meanings of the Verb chyk= ~ sykh= ‘to go out, to leave’ in Southern Siberian Turkic languages and Kipchak languages

2020 ◽  
pp. 85-99
Author(s):  
O. Yu. Shagdurova ◽  
E. V. Tyuntesheva
Keyword(s):  
World View ◽  
Space Time ◽  
Semantic Structure ◽  
Time Interval ◽  
Motion Verbs ◽  
Temporal Intervals ◽  
Turkic Languages ◽  
Temporal Aspect ◽  
Linguistic Groups ◽  
To Come

The article describes the semantic structure of one of the most polysemantic motion verbs in Turkic languages, namely the verb čïq= ~ sïx= and the correlating Tuvan verb ün=. The secondary meanings of these verbs in South- ern Siberian Turkic languages (Altai, Khakas, Tuvan) are analyzed in comparison with Kipchak languages. The verb čïq= ~ sïx= has been actively developing its meaning since it was fixed in the ancient Turkic monuments. This verb was found to possess similar meanings in various Turkic languages. At the same time, čïq= ~ sïx= is combined with different words in these languages. Regional values or values specific to specific languages are also detected. The languages under consideration are divided according to the action values expressed by constructions with the verb čïq= and its analogs: the beginning in the Turkic languages of Siberia and the completion, exhaustion of action in non-Siberian languages. It may be a manifestation of Mongolian influence on the Siberian languages, since the semantics of initialization is characteristic of the Mongolian gar=, the semantic structure of which is almost similar to the Turkic čïq= and ün=. The secondary meanings of the verb considered reflect the representations of linguistic groups associated with such concepts as top / bottom, previous / subsequent (in time). The semantics of čïq= ~ sïx= and ün= reflects the spatial-temporal aspect of the Turkic world view. These verbs combine the meanings of various vectors of direction (horizontally and vertically), as well as motions taking place on various spatial-temporal intervals, including the opposite ones: the manifestation of an object / the beginning of an action (to appear / to begin; to begin, to start some activity); the action during some space-time interval (to overcome any space / to overcome any period; to happen, to occur); the disappearance of an object / the completion of an action (to disappear / to come to an end; to finish, to complete some activity).

Toward an understanding of cosmopolitanism in deep time: a case study of ammonoids from the middle Permian to the Middle Triassic

Paleobiology ◽  
2020 ◽  
Vol 46 (4) ◽  
pp. 533-549
Author(s):  
Xu Dai ◽  
Haijun Song
Keyword(s):  
Mass Extinction ◽  
Middle Triassic ◽  
Theoretical Models ◽  
Geographic Range ◽  
Middle Permian ◽  
Time Interval ◽  
Mass Extinctions ◽  
Deep Time ◽  
Underlying Mechanisms ◽  
Selective Extinction

AbstractCosmopolitanism occurred recurrently during the geologic past, especially after mass extinctions, but the underlying mechanisms remain poorly known. Three theoretical models, not mutually exclusive, can lead to cosmopolitanism: (1) selective extinction in endemic taxa, (2) endemic taxa becoming cosmopolitan after the extinction and (3) an increase in the number of newly originated cosmopolitan taxa after extinction. We analyzed an updated occurrence dataset including 831 middle Permian to Middle Triassic ammonoid genera and used two network methods to distinguish major episodes of ammonoid cosmopolitanism during this time interval. Then, we tested the three proposed models in these case studies. Our results confirm that at least two remarkable cosmopolitanism events occurred after the Permian–Triassic and late Smithian (Early Triassic) extinctions, respectively. Partitioned analyses of survivors and newcomers revealed that the immediate cosmopolitanism event (Griesbachian) after the Permian–Triassic event can be attributed to endemic genera becoming cosmopolitan (model 2) and an increase in the number of newly originated cosmopolitan genera after the extinction (model 3). Late Smithian cosmopolitanism is caused by selective extinction in endemic taxa (model 1) and an increase in the number of newly originated cosmopolitan genera (model 3). We found that the survivors of the Permian–Triassic mass extinction did not show a wider geographic range, suggesting that this mass extinction is nonselective among the biogeographic ranges, while late Smithian survivors exhibit a wide geographic range, indicating selective survivorship among cosmopolitan genera. These successive cosmopolitanism events during severe extinctions are associated with marked environmental upheavals such as rapid climate changes and oceanic anoxic events, suggesting that environmental fluctuations play a significant role in cosmopolitanism.

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