Statistical properties of near threshold responses to brief sounds in the MES auditory cortex of the anesthetized dog

1959 ◽  
Vol 196 (6) ◽  
pp. 1168-1174
Author(s):  
Archie R. Tunturi
Keyword(s):  
Standard Deviation ◽  
Auditory Cortex ◽  
Evoked Potential ◽  
Zero Crossing ◽  
Essentially Normal ◽  
Average Potential ◽  
Posterior Direction ◽  
The Mean ◽  
Anterior Posterior ◽  
Near Threshold

Evoked responses to near threshold p pulses recorded with a 50-channel cathode ray oscilloscope from the MES auditory cortex were analyzed statistically. Observations were taken at 3-msec. epochs for approximately 180 msec. Density functions of the evoked potential at these epochs were essentially normal. The average potential from a single electrode consisted of an initial positive followed by a negative component. The correlation coefficient between the positive and negative components was zero suggesting independence. Standard deviation increased during the positive component of a response decreasing to the zero crossing or was followed by a secondary component. Spatially, in the anterior-posterior direction, the average potentials decremented to approximately zero in 2–4 mm. The decrement was less prominent dorso-ventrally. Spatially, the standard deviation showed the same pattern as the mean.

Components of the evoked potential in the MES auditory cortex

1960 ◽  
Vol 199 (3) ◽  
pp. 529-534 ◽  
Author(s):  
Archie R. Tunturi
Keyword(s):  
Standard Deviation ◽  
Auditory Cortex ◽  
Electrical Activity ◽  
Evoked Potential ◽  
Random Variable ◽  
Positive Component ◽  
Negative Component ◽  
Spontaneous Electrical Activity ◽  
Covariance Term ◽  
The Mean

The electrical activity during the potential evoked by a p pulse was analyzed statistically by considering amplitude at each 3-msec. epoch a random variable. The rise in standard deviation during the evoked potential was abolished a) by local cocaine on the cortex, b) by a preceding evoked potential and c) by ischemia. The residual mean positive component, with zero standard deviation, was subtracted from the mean of the evoked potential. This yielded a positive-negative component, with which the spontaneous electrical activity is believed to interact. The evoked potential is thus described as the sum of the three random variables: a) spontaneous electrical activity, b) positive component, and c) positive-negative component, with a covariance term involving the spontaneous electrical activity and the positive-negative component.

Statistical properties of spontaneous electrical activity in the MES auditory cortex of the anesthetized dog

1959 ◽  
Vol 196 (6) ◽  
pp. 1175-1180 ◽  
Author(s):  
Archie R. Tunturi
Keyword(s):  
Standard Deviation ◽  
Electrical Activity ◽  
Correlation Coefficients ◽  
Positive Component ◽  
Chi Square ◽  
True Response ◽  
Spontaneous Electrical Activity ◽  
Posterior Direction ◽  
The Mean ◽  
Anterior Posterior

The spontaneous electrical activity was sampled at 2-second intervals from 50 electrodes on the MES area. Chi-square tests indicated normality for the amplitude values of potential obtained at each electrode. The range for standard deviations was 43–113 µv but averaged between 77 and 85 for three animals. Correlation coefficients greater than 0.7 were obtained between electrodes 2 mm apart in the anterior-posterior direction with a decrement to 0.4 at a separation of 4 mm. Dorso-ventrally, correlations greater than 0.7 were obtained between electrodes 4–6 mm apart, suggesting a strip-like character. Low values of correlation were obtained between an electrode in the MES area and an electrode on the AES or PES area. Assuming independence of the true response and spontaneous electrical activity the mean curve and standard deviation curve of the true response were computed. The standard deviation curve of the true response increased during the positive component gradually decreasing toward the end of the negative component.

Statistics of spontaneous electrical activity of supra- and ectosylvian gyri of the dog

1963 ◽  
Vol 204 (1) ◽  
pp. 51-59
Author(s):  
Archie R. Tunturi
Keyword(s):  
Standard Deviation ◽  
Electrical Activity ◽  
Negative Correlation ◽  
Evoked Potential ◽  
Correlation Coefficients ◽  
Moderate Correlation ◽  
Spontaneous Electrical Activity ◽  
Suprasylvian Gyrus ◽  
The Mean ◽  
Standard Deviations

The standard deviations of the spontaneous electrical activity (SEA) of the suprasylvian gyrus (SSG) ranged between 57–131 µv and for the middle ectosylvian (MES) gyrus, 88–175 µv. Correlation coefficients, r, served to distinguish three regions of the SSG. The rostral showed low correlation with the middle, high correlation with the caudal, and low to negative correlation with the MES. The middle showed moderate correlation with the MES, and the caudal showed zero to negative correlation with the MES. Within the SSG, correlation was low and in the MES high, for spacings of 2 mm. Cocaine applied to both areas sharpened the boundaries at the sulci, reduced standard deviations, did not affect the correlation between the caudal SSG and the MES area, and increased r between all locations in the MES but not in the SSG. Cocaine on the SSG had no effect on the mean and standard deviation of the evoked potential in the MES, but decreased r of the SEA significantly.

scholarly journals The center of pressure progression characterizes the dynamic function of high-arched feet during walking

2020 ◽  
Vol 2 (1) ◽  
Author(s):  
Bo Li ◽  
Qipeng Xiang ◽  
Xianyi Zhang
Keyword(s):  
Center Of Pressure ◽  
Clinical Intervention ◽  
Mean Velocity ◽  
Gait Characteristics ◽  
Risk Of Injury ◽  
Dynamic Function ◽  
Posterior Direction ◽  
The Mean ◽  
Two Phases ◽  
Anterior Posterior

Abstract Background The medial longitudinal arch height has an effect on kinetic parameters during gait and might be related to the risk of injury. For the assessment of foot structures, the center of pressure (COP) trajectory is a more reliable and practical parameter than plantar pressure. This study aimed to clarify the COP trajectory and velocity characteristics in the medial-lateral and anterior-posterior direction of individuals with a high-arched foot during barefoot walking. Methods Sixty-two healthy young adults were asked to walk over a Footscan pressure plate to record the COP parameters during the stance phase of walking. Results Compared to normal arched feet, the COP during forefoot contact and foot flat phases of high-arched feet shifted anteriorly (19.9 mm and 15.1 mm, respectively), and the mean velocity of COP in anterior-posterior direction decreased by 0.26 m/s and increased by 0.044 m/s during these two phases respectively. Conclusions The findings of this study suggest that the displacement and velocity of COP in anterior-posterior direction was different between high-arched and normal-arched subjects during barefoot walking, which can be used for the assessment of gait characteristics for high-arched individuals. The results of this study may provide insights into modifying clinical intervention for individuals with high-arched feet to enhance rehabilitation and prevent injuries and have implications for assessing the design of footwear and foot orthotics. Graphical abstract

Effect of spontaneous activity on afferent response in the MES auditory cortex of the dog

1959 ◽  
Vol 197 (5) ◽  
pp. 1141-1146
Author(s):  
Archie R. Tunturi
Keyword(s):  
Standard Deviation ◽  
Auditory Cortex ◽  
Electrical Activity ◽  
Spontaneous Activity ◽  
Evoked Potential ◽  
Random Variables ◽  
Spontaneous Electrical Activity ◽  
Cocaine Hydrochloride ◽  
Afferent Response ◽  
Stimulation Of

Treating the spontaneous electrical activity (SEA) and the evoked potential due to a p pulse at the MES auditory cortex as random variables at 3-msec. epochs, an increase in standard deviation during the evoked potential was found suggesting the occurrence of two statistical processes. By suitable application of cocaine hydrochloride locally to the cortex, it was possible to suppress the standard deviation of SEA and obtain a potential with no or little variance. This potential was defined as the ‘afferent response’ representing the activity due to volleys from the ear. It was concluded that the locally arising SEA has connections to the nerve elements causing the afferent response, thus producing the variance of the evoked potential. The SEA, therefore, is an information destroying process, since it reduces the detectability of response from stimulation of the ear.

At Least One Standard Deviation Above the Mean

1969 ◽  
Vol 14 (9) ◽  
pp. 470-471
Author(s):  
M. DAVID MERRILL
Keyword(s):  
Standard Deviation ◽  
The Mean

The Estimation of Blood Platelet Survival

1972 ◽  
Vol 28 (03) ◽  
pp. 447-456 ◽  
Author(s):  
E. A Murphy ◽  
M. E Francis ◽  
J. F Mustard
Keyword(s):  
Standard Deviation ◽  
Least Squares ◽  
Experimental Error ◽  
Blood Platelet ◽  
Least Squares Estimation ◽  
Systematic Relationship ◽  
Platelet Survival ◽  
The Mean ◽  
Normally Distributed

SummaryThe characteristics of experimental error in measurement of platelet radioactivity have been explored by blind replicate determinations on specimens taken on several days on each of three Walker hounds.Analysis suggests that it is not unreasonable to suppose that error for each sample is normally distributed ; and while there is evidence that the variance is heterogeneous, no systematic relationship has been discovered between the mean and the standard deviation of the determinations on individual samples. Thus, since it would be impracticable for investigators to do replicate determinations as a routine, no improvement over simple unweighted least squares estimation on untransformed data suggests itself.

PENGARUH PENDIDIKAN KESEHATAN REPRODUKSI PADA PEER GROUP (TEMAN SEBAYA) TERHADAP PENGETAHUAN DAN PERSEPSI REMAJA TENTANG PENDEWASAAN USIA PERKAWINAN DI SMA NEGERI 1 KECAMATAN NAMORAMBE KAB. DELI SERDANG 2018

2020 ◽  
Vol 1 (2) ◽  
pp. 56-66
Author(s):  
Irma Linda
Keyword(s):  
Standard Deviation ◽  
Health Education ◽  
Reproductive Health ◽  
Peer Group ◽  
Peer Groups ◽  
A Value ◽  
Significant Difference ◽  
Reproductive Health Education ◽  
The Mean ◽  
Adolescent Perceptions

Background: Early marriages are at high risk of marital failure, poor family quality, young pregnancies at risk of maternal death, and the risk of being mentally ill to foster marriage and be responsible parents. Objective: To determine the effect of reproductive health education on peer groups (peers) on the knowledge and perceptions of adolescents about marriage age maturity. Method: This research uses the Quasi experimental method with One group pre and post test design, conducted from May to September 2018. The statistical analysis used in this study is a paired T test with a confidence level of 95% (α = 0, 05). Results: There is an average difference in the mean value of adolescent knowledge between the first and second measurements is 0.50 with a standard deviation of 1.922. The mean difference in mean scores of adolescent perceptions between the first and second measurements was 4.42 with a standard deviation of 9.611. Conclusion: There is a significant difference between adolescent knowledge on the pretest and posttest measurements with a value of P = 0.002, and there is a significant difference between adolescent perceptions on the pretest and posttest measurements with a value of p = 0.001. Increasing the number of facilities and facilities related to reproductive health education by peer groups (peers) in adolescents is carried out on an ongoing basis at school, in collaboration with local health workers as prevention of risky pregnancy.

Regularity and latency of units in ventral cochlear nucleus: implications for unit classification and generation of response properties

1988 ◽  
Vol 60 (1) ◽  
pp. 1-29 ◽  
Author(s):  
E. D. Young ◽  
J. M. Robert ◽  
W. P. Shofner
Keyword(s):  
Standard Deviation ◽  
Cochlear Nucleus ◽  
Interspike Interval ◽  
Rate Adaptation ◽  
Stellate Cells ◽  
Instantaneous Rate ◽  
Ventral Cochlear Nucleus ◽  
Bushy Cell ◽  
Low Pass ◽  
The Mean

1. The responses of neurons in the ventral cochlear nucleus (VCN) of decerebrate cats are described with regard to their regularity of discharge and latency. Regularity is measured by estimating the mean and standard deviation of interspike intervals as a function of time during responses to short tone bursts (25 ms). This method extends the usual interspike-interval analysis based on interval histograms by allowing the study of temporal changes in regularity during transient responses. The coefficient of variation (CV), equal to the ratio of standard deviation to mean interspike interval, is used as a measure of irregularity. Latency is measured as the mean and standard deviation of the latency of the first spike in response to short tone bursts, with 1.6-ms rise times. 2. The regularity and latency properties of the usual PST histogram response types are shown. Five major PST response type classes are used: chopper, primary-like, onset, onset-C, and unusual. The presence of a prepotential in a unit's action potentials is also noted; a prepotential implies that the unit is recorded from a bushy cell. 3. Units with chopper PST histograms give the most regular discharge. Three varieties of choppers are found. Chop-S units (regular choppers) have CVs less than 0.35 that are approximately constant during the response; chop-S units show no adaptation of instantaneous rate, as measured by the inverse of the mean interspike interval. Chop-T units have CVs greater than 0.35, show an increase in irregularity during the response and show substantial rate adaptation. Chop-U units have CVs greater than 0.35, show a decrease in irregularity during the response, and show a variety of rate adaptation behaviors, including negative adaptation (an increase in rate during a short-tone response). Irregular choppers (chop-T and chop-U units) rarely have CVs greater than 0.5. Choppers have the longest latencies of VCN units; all three groups have mean latencies at least 1 ms longer than the shortest auditory nerve (AN) fiber mean latencies. 4. Chopper units are recorded from stellate cells in VCN (35, 42). Our results for chopper units suggest a model for stellate cells in which a regularly firing action potential generator is driven by the summation of the AN inputs to the cell, where the summation is low-pass filtered by the membrane capacitance of the cell.(ABSTRACT TRUNCATED AT 400 WORDS)

Sign in / Sign up

Export Citation Format

Share Document