Effect of background loading on perception of inspiratory loads

1984 ◽  
Vol 56 (2) ◽  
pp. 404-410 ◽  
Author(s):  
W. R. Revelette ◽  
F. W. Zechman ◽  
D. E. Parker ◽  
R. L. Wiley
Keyword(s):  
Magnitude Estimation ◽  
Power Law ◽  
Detection Threshold ◽  
Subjective Magnitude ◽  
Mouth Pressure ◽  
Perceptual Performance ◽  
The Difference ◽  
Inspiratory Load ◽  
Background Load

The effect of background loading on magnitude estimation of added elastic and resistive inspiratory loads was determined. An analogous study involving estimation of the heaviness of weights in the hand was also performed. Perceptual performance was assessed using Stevens' power law psi = k phi n, where psi is the subjective magnitude, phi is the peak mouth pressure generated with an inspiratory load or the weight of the load in grams for the heaviness estimation, and the exponent n characterizes perceptual performance. The value of n was determined for the control and background conditions for each study. The results for both inspiratory loading studies and the heaviness estimation experiment indicate that background loading is associated with a significant increase in the exponent for magnitude estimation (P less than 0.05). Adjustment of the stimulus scale by subtracting the difference in peak mouth pressures generated during resting breathing between control and background-loaded conditions for the inspiratory loading studies, or the weight of the background load in the heaviness estimation experiment, converted the exponents obtained under background-loaded conditions to values that were not significantly different from those for control (P greater than 0.05). These results are consistent with the theory suggesting that an increase in detection threshold, produced by the background load, is responsible for the increase in exponent for magnitude estimation.

Plasticity of the mechanism subserving inspiratory load perception

1987 ◽  
Vol 62 (5) ◽  
pp. 1901-1906 ◽  
Author(s):  
W. R. Revelette ◽  
R. L. Wiley
Keyword(s):  
Random Order ◽  
Short Term ◽  
Mouth Pressure ◽  
Short Term Exposure ◽  
Significant Difference ◽  
Perceptual Performance ◽  
Resistive Loads ◽  
The Stability ◽  
Load Perception ◽  
Inspiratory Load

The objective of this study was to determine the stability of the function describing subjects' magnitude estimates of added inspiratory resistive loads following short-term exposure (STE) to a high but nonfatiguing, inspiratory load. Four inspiratory resistive loads (8.9–35.7 cmH2O X l–1 X s) were presented twice each in random order. Subjects were asked to estimate load magnitude by force of handgrip. Perceptual performance was quantified using Stevens power law, psi = k phi n, where psi is the subject's estimate, k is a constant, and phi is the peak mouth pressure developed against the load. The exponent n represents the slope of the line in the plot of log psi vs. log phi. After a 2-min period in which subjects were required to generate 80% of their maximum inspiratory pressure against a high resistance, the load estimation protocol was repeated. Estimates were significantly reduced compared to control; however, there was no significant difference in the exponent for magnitude functions between conditions. Similar results were obtained in a second parallel experiment involving magnitude estimation of weights lifted by the elbow flexors. The results suggest plasticity in the mechanism(s) subserving sensation of added loads to breathing and that such plasticity is a general feature of sensation arising from nonrespiratory muscles as well.

Hearing in Mice by GSR Audiometry: II. Magnitude of Unconditioned GSR as a Function of Intensity and Frequency Interactions

1968 ◽  
Vol 11 (1) ◽  
pp. 169-178 ◽  
Author(s):  
Alan Gill ◽  
Charles I. Berlin
Keyword(s):  
Power Law ◽  
Response Magnitude ◽  
Single Units ◽  
Spectral Content ◽  
Hearing Sensitivity ◽  
Subjective Magnitude ◽  
Orderly Fashion ◽  
Viiith Nerve

The unconditioned GSR’s elicited by tones of 60, 70, 80, and 90 dB SPL were largest in the mouse in the ranges around 10,000 Hz. The growth of response magnitude with intensity followed a power law (10 .17 to 10 .22 , depending upon frequency) and suggested that the unconditioned GSR magnitude assessed overall subjective magnitude of tones to the mouse in an orderly fashion. It is suggested that hearing sensitivity as assessed by these means may be closely related to the spectral content of the mouse’s vocalization as well as to the number of critically sensitive single units in the mouse’s VIIIth nerve.

Pleasure as a Sign of Efficacy of Mental Activity

1997 ◽  
Vol 2 (3) ◽  
pp. 226-234 ◽  
Author(s):  
Michel Cabanac ◽  
Chantal Pouliot ◽  
James Everett
Keyword(s):  
Evolutionary Psychology ◽  
Magnitude Estimation ◽  
Mental Activity ◽  
Point Of View ◽  
Macintosh Computer ◽  
Science Students ◽  
Cognitive Efficiency ◽  
Sensory Pleasure ◽  
The Difference ◽  
Mental Tasks

Previous work has shown that sensory pleasure is both the motor and the sign of optimal behaviors aimed at physiological ends. From an evolutionary psychology point of view it may be postulated that mental pleasure evolved from sensory pleasure. Accordingly, the present work tested empirically the hypothesis that pleasure signals efficacious mental activity. In Experiment 1, ten subjects played video-golf on a Macintosh computer. After each hole they were invited to rate their pleasure or displeasure on a magnitude estimation scale. Their ratings of pleasure correlated negatively with the difference par minus performance, i.e., the better the performance the greater the pleasure reported. In Experiments 2 and 3, the pleasure of reading poems was correlated with comprehension, both rated by two groups of subjects, science students and arts students. In the majority of science students pleasure was significantly correlated with comprehension. Only one arts student showed this relationship; this result suggests that the proposed relationship between pleasure and cognitive efficiency is not tautological. Globally, the results support the hypothesis that pleasure is aroused by the same mechanisms, and follows the same laws, in physiological and cognitive mental tasks and also leads to the optimization of performance.

Scaling Behavior of Dynamic Hysteresis in Hard PZT Bulk Ceramics under Influence of Compressive Stress

2008 ◽  
Vol 55-57 ◽  
pp. 281-284 ◽  
Author(s):  
N. Wongdamnern ◽  
Athipong Ngamjarurojana ◽  
Supon Ananta ◽  
Yongyut Laosiritaworn ◽  
Rattikorn Yimnirun
Keyword(s):  
Energy Dissipation ◽  
Electric Field ◽  
Mechanical Stress ◽  
Compressive Stress ◽  
Power Law ◽  
Field Amplitude ◽  
Electric Field Amplitude ◽  
Bulk Ceramic ◽  
Compressive Stresses ◽  
The Difference

Effects of electric field-amplitude and mechanical stress on hysteresis area were investigated in partially depoled hard PZT bulk ceramic. At any compressive stress, the hysteresis area was found to depend on the field-amplitude with a same set of exponents to the power-law scaling. Consequently, inclusion of compressive stresses into the power-law was also obtained in the form of < A – Aσ=0 > α E05.1σ1.19 which indicated the difference of the energy dissipation between the under-stress and stress-free conditions.

Relationship between the Differences of Odor Detection Threshold Values Measured by Different Methods and some of the Physicochemical Properties

2013 ◽  
Vol 807-809 ◽  
pp. 451-455 ◽  
Author(s):  
Di Fang ◽  
Jie Min Liu ◽  
Qin Yi
Keyword(s):  
Physicochemical Properties ◽  
Functional Group ◽  
Saturated Vapor ◽  
Detection Threshold ◽  
Threshold Values ◽  
Odor Detection ◽  
Linear Relationships ◽  
Odor Detection Threshold ◽  
The Difference ◽  
The Relationship

The amount of sample can enter the nasal cavity depends on the physiochemical characteristics such as distribution, volatility and solubility. It can be suspected that the difference of odor detection threshold (ODT) measured by different methods is related to the physicochemical properties of compounds. To investigate the relationship between ODT differences and the physicochemical properties of compounds, ODT values of four series of organic compounds were measured by triangle odor bag method and gas chromatography and olfactometry method; the results were compared and the absolute differences were calculated. Relationship between ODT differences and the type of functional group and some of the physicochemical properties of compounds was analyzed. The results showed the type of functional group had significant effect on the differences. Certain linear relationships between the logarithmic value of differences and the logarithmic values of saturated vapor pressure and molecular weight were observed.

scholarly journals Limitation of symmetry breaking by gravitational collapse: the revisit of Lin–Mestel–Shu instability

2020 ◽  
Vol 498 (1) ◽  
pp. 310-319
Author(s):  
Tirawut Worrakitpoonpon
Keyword(s):  
Gravitational Collapse ◽  
Power Law ◽  
Particle Number ◽  
Density Fluctuations ◽  
Shape Evolution ◽  
Critical Number ◽  
Initial State ◽  
Final State ◽  
Numerical Work ◽  
The Difference

ABSTRACT We revisit the topic of shape evolution during the spherical collapse of an N-body system. Our main objective is to investigate the critical particle number below which, during a gravitational collapse, the amplification of triaxiality from initial fluctuations is effective, and above which it is ineffective. To this aim, we develop the Lin–Mestel–Shu theory for a system of particles initially with isotropic velocity dispersion and with a simple power-law density profile. We first determine, for an unstable cloud, two radii corresponding to the balance of two opposing forces and their fluctuations: such radii fix the sizes of the non-collapsing region and the triaxial seed from density fluctuations. We hypothesize that the triaxial degree of the final state depends on which radius is dominant prior to the collapse phase leading to a different scheme of the self-consistent shape evolution of the core and the rest of the system. The condition where the two radii are equal therefore identifies the critical particle number, which can be expressed as the function of the parameters of initial state. In numerical work, we can pinpoint such a critical number by comparing the virialized flattening with the initial flattening. The difference between these two quantities agrees with the theoretical predictions only for the power-law density profiles with an exponent in the range [0, 0.25]. For higher exponents, results suggest that the critical number is above the range of simulated N. We speculate that there is an additional mechanism, related to strong density gradients that increases further the flattening, requiring higher N to further weaken the initial fluctuations.

FRACTAL METHODS APPLIED TO DESCRIBE CELLULAR AUTOMATON COMBAT MODELS

Fractals ◽  
2001 ◽  
Vol 09 (02) ◽  
pp. 177-184 ◽  
Author(s):  
MICHAEL K. LAUREN
Keyword(s):  
Cellular Automaton ◽  
Complexity Theory ◽  
Power Law ◽  
Chaotic Systems ◽  
Probability Distributions ◽  
High Dimensional ◽  
Compelling Evidence ◽  
Military Equipment ◽  
The Difference ◽  
Maneuver Warfare

Analysis of warfare data provides compelling evidence that intensity of conflicts obeys a power-law (fractal) dependence on frequency. There is also evidence for the existence of other power-law dependences and traits characteristic of high-dimensional chaotic systems, such as fat-tailed probability distributions and intermittency in warfare data. In this report, it is discussed how a cellular automaton model used to describe modern maneuver warfare produces casualty distributions which exhibit these properties. This points to a possible origin of the characteristics of the larger timescale data. More interesting, the techniques of fractal analysis offer a method by which to characterize these behaviors, and to quantify the difference between models based on complexity theory (such as cellular automata models), and more traditional combat models based on the physics of military equipment.

Reversal of Asymmetry in Human Perceptual Performance as a Function of Labeling, Mode of Response, and Familiarity

1981 ◽  
Vol 52 (1) ◽  
pp. 183-193 ◽  
Author(s):  
Henry L. Dee ◽  
H. Julia Hannay
Keyword(s):  
Visual Field ◽  
Left Visual Field ◽  
Hemispheric Asymmetry ◽  
Visual Complexity ◽  
Visual Stimuli ◽  
High Complexity ◽  
Hemispheric Processing ◽  
Verbal Labels ◽  
Perceptual Performance ◽  
The Difference

It has previously been demonstrated that certain characteristics of the stimulus, specifically visual complexity and verbal association value, as well as mnemonic factors are important in producing the usually obtained asymmetry in human perceptual performance, and thus presumably, hemispheric asymmetry of function. The present research demonstrated that the usual superiority of the left visual field for high-complexity, low-association-value visual forms can be reversed by the acquisition and use of verbal labels for such stimuli but is only attenuated when the labels are not used to respond to the stimuli. Simple familiarity with the visual stimuli attenuated the difference between the fields, but here there was no reversal. Implications of these results for hemispheric processing are discussed.

Ratio Abstraction by 6-Month-Old Infants

2007 ◽  
Vol 18 (8) ◽  
pp. 740-745 ◽  
Author(s):  
Koleen McCrink ◽  
Karen Wynn
Keyword(s):  
Magnitude Estimation ◽  
Human Infants ◽  
Common Ratio ◽  
Human Adults ◽  
The Difference ◽  
Estimation System ◽  
Mathematical Operations ◽  
Approximate Magnitude

Human infants appear to be capable of the rudimentary mathematical operations of addition, subtraction, and ordering. To determine whether infants are capable of extracting ratios, we presented 6-month-old infants with multiple examples of a single ratio. After repeated presentations of this ratio, the infants were presented with new examples of a new ratio, as well as new examples of the previously habituated ratio. Infants were able to successfully discriminate two ratios that differed by a factor of 2, but failed to detect the difference between two numerical ratios that differed by a factor of 1.5. We conclude that infants can extract a common ratio across test scenes and use this information while examining new displays. The results support an approximate magnitude-estimation system, which has also been found in animals and human adults.

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