Psychophysical Relationships Research Articles

How Should Soundscape Optimization from Perceived Soundscape Elements in Urban Forests by the Riverside Be Performed?

Urban forests by the riverside are important habitats for various animals and contribute various soundscapes for citizens. Unfortunately, urban forests are exposed to the influence of riverside traffic noises from freeways. This study aims to explore the spatial and temporal variation of soundscape, conduct soundscape optimization for multiple parameters, and find a balance and its interval of soundscape elements through optimizing a soundscape map. Questionnaires and measuring equipment were used to gather soundscape information in an urban forested area in Fuzhou, China. Diurnal variations and soundscape mapping were used to analyze spatial and psychophysical relationships between soundscape drivers. We then conducted optimization for a soundscape map, which included normalization, critical value determination, target interval of optimal SPL determination, and modification of SPL and mapping. Our findings suggest that biological activities and natural phenomena are potential drivers for diurnal variation of soundscapes, especially tidal phenomena contributing water and shipping soundscapes. Our results also suggest that all the high values of perceived soundscapes were found at the southwest corner of the study area, which includes both riverside and urban forest elements. Furthermore, we suggest combining both optimal soundscape and SPL correction maps to aid in sustainable design in urban forests. This can contribute to the understanding and methodology of soundscape map optimization in urban forests when proposing suitable design plans and conservation of territorial sound.

Wellbeing at home: a mediation analysis of residential satisfaction, comfort, and home attachment

AbstractIn the study of residential satisfaction in architectural design different physical comfort domains have received the most attention. But with this comfort-driven approach, residential satisfaction is reduced to a psychophysical relationship. Adding psychological substance to the design process, the paper argues that a distinction should be made between residential satisfaction and home attachment and that we need to consider home attachment as a mediator variable for comfort. The aim of the paper is to empirically assess whether the mediation, if it exists at all, is partial or complete. Distinguishing different forms of comfort, a set of alternative structural equation models are tested with data from a 14-nation population survey in Europe. The result of the model tests is that our wellbeing at home comes in two forms—satisfaction and attachment—and that there is partial as well as complete mediation of home attachment on satisfaction depending on the kind of comfort studied.

The Scales Project, a cross-national dataset on the interpretation of thermal perception scales

Thermal discomfort is one of the main triggers for occupants’ interactions with components of the built environment such as adjustments of thermostats and/or opening windows and strongly related to the energy use in buildings. Understanding causes for thermal (dis-)comfort is crucial for design and operation of any type of building. The assessment of human thermal perception through rating scales, for example in post-occupancy studies, has been applied for several decades; however, long-existing assumptions related to these rating scales had been questioned by several researchers. The aim of this study was to gain deeper knowledge on contextual influences on the interpretation of thermal perception scales and their verbal anchors by survey participants. A questionnaire was designed and consequently applied in 21 language versions. These surveys were conducted in 57 cities in 30 countries resulting in a dataset containing responses from 8225 participants. The database offers potential for further analysis in the areas of building design and operation, psycho-physical relationships between human perception and the built environment, and linguistic analyses.

Verbal Expression of Piano Sounds and Psychophysics

One unique feature of the piano is the continual decay of the sound after a key is pressed until the finger is lifted from the key. In this process, the sound from the piano attenuates the level while slightly changing the frequency structure. Further, when the pianist releases the key, but presses the forte pedal with the foot, the sound continues. The pianist can finely adjust the decay pattern that follows pressing a key by moving fingers and operating pedal. Thus, one of the major factors that can realize the expression of a brilliant piano performance is the decay of the sound itself, and the ability of pianist precisely control the characteristics of that decay to create a beautiful stream of sound. As shown in Fig.1, the dynamic characteristics of hearing greatly affect the perception of decaying sounds. The sound of a piano after a keystroke continues to attenuate, however, if the legato technique is performed with a finger held on a key or the forte pedal being pressed, the sounds played one after another will overlap. If dissonant sounds are generated over time, the sequence provides an unpleasant impression. If the decaying part of the preceding sound and the rising part of the following sound are superimposed, an acoustically dissonant sound is generated. Reflecting on the dynamic characteristics of hearing, due to the overshoot of the following sound, the decaying part of the preceding sound is masked, dissonance is not heard, and the melody progresses smoothly. Thus, it can be said that the variety of expressions from a piano is large because piano sound is a decaying sound, and the pianist skillfully adjusts attenuation patterns by using the dynamic characteristics of hearing. Dynamic characteristics of hearing can be investigated through psychophysical procedures under controlled conditions (Namba, S. 2013). However, it is not easy to describe the world of music in the heart, although this world is vividly expressed in excellent novels and essays. Research on the correspondence between the beauty of the sound of a piano in the world of the mind and as a precisely measured physical quantity is not highly remarkable. One reasons for this is the world of beauty in piano performances as depicted in novels is delicate, subtle and complex. Further, the physical quantities of piano sounds measured from various aspects are highly precise and complicated. Such complications are a barrier to finding psychophysical laws that reveal the relationship between the world of the mind and physical quantities. Historically, psychophysical measurements have not been benefical for assessing complex events. This is because of the difficulty in ensuring the reliability of experiments or in accurately controlling stimulus conditions in psychophysical experiments. In the case of a one dimensional attribute such as loudness, even if the physical quantity of sound is complex, it can be controlled by psychophysical methods. However, the tone quality that is an important attribute in the evaluation of piano sounds is multidimensional, and the physical quantity that affects the tone quality is also multidimensional. Therefore, it is not easy to find the psychophysical law between the two. If we can solve these problems, we should from the physical quantities, be able to correlate beautiful piano sounds that are described in novels. Not only that, it would be an important step on the path to elucidation the psychophysical relationships of complex events in daily life. Many studies on tone quality have been conducted in which target sound sources were selected to limit factors affecting the tone quality. Verbal expressions of tone quality, which is a multidimensional attribute, have been addressed also by selecting only a small number of adjectives. Further, statistical methods such as factor analysis were used in the selection process.(View PDF for the rest of the abstract.)

Psychophysical Relations between Interacted Fabric Thermal‐Tactile Properties and Psychological Touch Perceptions

AbstractTouch sensation perception includes three processes – physical, neurophysiological and psychological. Psychophysical relationships that bridge physical and psychological results have varied. Meanwhile, interactive effects of thermal‐tactile physical features have seldom been investigated. Therefore, this study aims to compare various hypothesized psychophysical relations, including monomode relations between single stimuli and single sensations, as well as multimode relations between multistimuli and sensory dimensions. Potential simultaneous effects from thermal‐tactile factors and their interactions are also explored. This study uses physical data, obtained from a simultaneous measurement instrument Fabric Touch Tester, and psychological data collected from over 200 subjects. The results imply that a universal psychophysical function relation can hardly be achieved. Different neural stimulation mechanisms seem to be better presented by dissimilar function relations. It is also found that thermal and tactile physical information can simultaneously affect all defined sensory dimensions – including smoothness, softness and warmth. Interaction effects from multistimuli are also concluded to be important predictors.Practical ApplicationsStudy of the relationship between psychological touch sensations and fabric physical properties has always been an attractive field in textile sensory research. Along with the increased demands on the touch comfort of clothing, precise quantitative characterization methods are eagerly needed in industry. A number of approaches have been proposed during past studies, including psychophysical laws and stepwise‐box‐linear regression. However, these resolutions focused on tactile properties and mechanical sensations only. Although the latest neurophysiological findings have enlarged the scope of thermal‐tactile properties, there is still a lack of investigation into interactive effects of both thermal and tactile properties. This work provides comparison studies on different types of psychophysical relations and particularly explores the interactive effects of multiple physical aspects. Proposed psychophysical relations are concluded with satisfied correlation coefficients to the subjective sensations. Such interactive multimode psychophysical relations could be used to advance current prediction models with stronger connections to neurophysiological perception mechanisms.

Both acoustic intensity and loudness contribute to time-series models of perceived affect in response to music.

Research in the fields of music and emotion has investigated relationships between acoustic properties of music and listeners' perception of affect in response to music. Specifically, the dimensions of arousal and valence that comprise a two-dimensional circumplex model of experienced affect (Russell, 1980, 2003) are commonly measured in experiments investigating the multiplicity of acoustic cues associated with perceived affect (Bailes & Dean, 2012; Dean & Bailes, 2010; Dean, Bailes, & Schubert, 2011; Gingras, Marin, & Fitch, 2014; Olsen & Stevens, 2013; Ritossa & Rickard, 2004; Schubert, 1999, 2004, 2013). With additional use of continuous perceptual measurements, a clearer picture of the real-time factors that underpin affective response to music as it unfolds through time is beginning to emerge.From causal experiments, time-series models of continuous responses to music from the Western classical tradition have shown that manipulations of acoustic intensity profiles of performed music, as measured by decibels (dB) in SPL, significantly influence listeners' real-time perception of affect and loudness (Dean et al., 2011). A strong impact of acoustic intensity on perceived loudness in music perception is to be expected, as a long tradition of psychophysical research reports an intimate (yet not straightforward) relationship between loudness and acoustic intensity (Canevet & Scharf, 1990; Fletcher & Munson, 1933; Florentine, Popper, & Fay, 2011; Olsen, 2014; Olsen, Stevens, & Tardieu, 2010; Scharf, 1978; Stevens, 1956). One would also expect, therefore, that where intensity predicts perceived loudness and perceived affect, loudness might either share with intensity a predictive capacity for perceived affect, or mediate the role of intensity when affective responses are modeled.Somewhat contrary to this hypothesis, time-series modeling of continuously perceived affect in response to one piece from the Western classical tradition (an extract from Dvorak's Slavonic Dance Opus 46, No. 1) included better prediction of perceived affect from acoustic intensity than from continuous loudness (Dean et al., 2011), with loudness not required as a component of the optimized model. The relevance of the surprising exclusion of loudness in this particular model is assessed in the present study. Is this phenomenon specific to the particular Dvorak piece, or is it more general across music with varied complexity and familiarity? As argued above, we expect that loudness will either share a predictive capacity with intensity or mediate the role of intensity when affective responses to more diverse musical stimuli are modeled. To investigate this hypothesis further, acoustic intensity and perceived loudness must be manipulated in a way that subtly distorts the inherently strong psychophysical relationship, so their potential influences on affect can be distinguished empirically. This is accomplished here with the manipulation of synthesized reverberation, an acoustic cue active for listeners' impressions of auditory space and perceived auditory distance, which in turn has been shown to affect perceived loudness of a sound source (Butler, Levy, & Neff, 1980; Lee, Cabrera, & Martens, 2012; Mershon, Desaulniers, Kiefer, Amerson, & Mills, 1981; Stecker & Hafter, 2000; Zahorik, Brungart, & Bronkhorst, 2005; but see, Zahorik & Wightman, 2001).Thus, the aim of the present article is to further address the predictive power of continuous intensity and loudness change in time-series models of perceived affect. This is achieved by manipulating continuous loudness perception without concurrent changes in the intensity profile of the stimulus; intensity changes that would normally be deemed necessary to manipulate loudness. Here, one group of participants continuously rated the affective elements of perceived arousal and valence (Experiment 1), while another participant group continuously rated loudness (Experiment 2). …

Oral perception of liquid volume changes with age.

Bolus volume has been widely studied, and research has demonstrated a variety of physiological impacts on swallowing and swallowing disorders. Oral perception of bolus volume has not, to our knowledge, been investigated in association with normal ageing processes. Research suggests many sensory changes with age, some within the oral cavity, and changes in swallowing function with age have been defined. The role of perception in oropharyngeal deglutition with age requires further investigation. The purpose of this study was to establish the psychophysical relationship between liquid volume and oral perception and examine changes with age. Healthy young and older adults were prospectively assessed using a magnitude estimation task differentiating five volumes of water delivered randomly to the oral cavity. Results suggest a fourfold increase in liquid volume is required by older participants to perceive an approximate twofold increase in the perception of volume compared with younger healthy adults. Sensory receptors in the oral cavity provide a feedback loop that modulates the swallowing motor response so that it is optimal for the size and consistency of the bolus. Changes in perception of bolus volume with age are consistent with other perceptual changes and may provide valuable information regarding sensorineural rehabilitation strategies in the future.

Forgiveness Therapy in the Relief of Discomfort

Patients present with a myriad of complaints. These complaints cover a range from the physical to the psychological. Many of the presenting symptoms and ramifications of the disease process can be a reflection of the psycho-physical relationship in all human beings. The practice of forgiveness has been discussed throughout history usually through a religious lens, yet, research points to forgiveness as a means to reduce anger, depression, to improve health and happiness and to increase selfesteem. It is interesting to note that it is forgiveness work that enables individuals to enable lasting personal change and move forward in a positive fashion. It is also interesting to note that forgiveness therapy is a crucial part of the hypnotherapeutic interaction when dealing with pain and other discomfort.

A Method for Developing Images of Clothes Based on Visual and Tactile Evaluations of “Thickness” and “Thinness”

The purpose of this study is to clarify the relationship between the visual and tactile evaluations of the “thickness” and “thinness” of a piece of fabric, and to develop photographs of pieces of fabric adapted to the described degree of “thickness” and “thinness” using the evaluation results. We carried out two fabric texture evaluation experiments, one using only visual perception (VE) and the other using both visual and tactile perceptions (VTE), for thinness and thickness using eleven types of actual fabric. Ten observers evaluated the thickness and thinness of the fabric samples using a 5-point scale. The results indicated that there were no significant differences between the VE and VTE evaluations. This result implies that visual recognition is predominant in fabric texture assessment. We then focused on the results of the VTE-based evaluations, which presented an overall judgment of fabric textures. Next, to expound on the method for developing photographs of fabric samples using these thickness and thinness evaluations, we focused on two physical properties: a light transmittance of the fabric as a visual factor, and a thickness parameter “T0” in the Kawabata evaluation system as a tactile factor. The relationships between the evaluation results and the physical properties of the former and the latter were clarified by correlation analysis. The former exhibited a higher correlation than the latter in terms of a psychophysical relationship. We therefore focused on the light transmittance of the fabric samples, and developed and evaluated photographs that changed illumination levels to indicate the thickness and thinness levels. The results revealed that altering the photographs based on the aforementioned evaluations improved the accuracy of fabric texture recognition.

Interpreting consumer preferences: Physicohedonic and psychohedonic models yield different information in a coffee-flavored dairy beverage

Designed experiments provide product developers feedback on the relationship between formulation and consumer acceptability. While actionable, this approach typically assumes a simple psychophysical relationship between ingredient concentration and perceived intensity. This assumption may not be valid, especially in cases where perceptual interactions occur. Additional information can be gained by considering the liking-intensity function, as single ingredients can influence more than one perceptual attribute. Here, 20 coffee-flavored dairy beverages were formulated using a fractional mixture design that varied the amount of coffee extract, fluid milk, sucrose, and water. Overall liking (liking) was assessed by 388 consumers using an incomplete block design (4 out of 20 prototypes) to limit fatigue; all participants also rated the samples for intensity of coffee flavor (coffee), milk flavor (milk), sweetness (sweetness) and thickness (thickness). Across product means, the concentration variables explained 52% of the variance in liking in main effects multiple regression. The amount of sucrose (β=0.46) and milk (β=0.46) contributed significantly to the model (p’s<0.02) while coffee extract (β=−0.17; p=0.35) did not. A comparable model based on the perceived intensity explained 63% of the variance in mean liking; sweetness (β=0.53) and milk (β=0.69) contributed significantly to the model (p’s<0.04), while the influence of coffee flavor (β=0.48) was positive but marginally (p=0.09). Since a strong linear relationship existed between coffee extract concentration and coffee flavor, this discrepancy between the two models was unexpected, and probably indicates that adding more coffee extract also adds a negative attribute, e.g. too much bitterness. In summary, modeling liking as a function of both perceived intensity and physical concentration provides a richer interpretation of consumer data.

Perceived Urgency and Annoyance of Auditory Alerts in a Driving Context

Complex in-vehicle technology and safety systems are finding their way into many cars on the road today. These systems require alerts and warnings that appropriately convey multiple levels of urgency, but if these are deemed excessively annoying, then their implementation may be of little consequence. In this study we used a well-documented psychophysical approach to identify the relationship between specific auditory parameters, perceived urgency and perceived annoyance. In agreement with existing literature, increases in all parameters led to increases in both urgency and annoyance - although differentially. Of the parameters investigated, only pulse rate exhibited a stronger psychophysical relationship with urgency than annoyance. The tradeoff between urgency and annoyance is of practical concern and results from this study provide a potential guideline to determine the viability of future in vehicle alerts based on this relationship.

A model for the perception of surface pressure on human foot

The psychophysical relationship between the magnitude of pressure on thirteen test locations of twenty healthy subjects' feet with four probe areas at three indentation speeds and the corresponding perceived sensations were analyzed. The dependency of pressure pain thresholds (PPT) on area, A, and speed, v, can be mathematically modeled in the form, PPTi = [ai + bLn(v)]Aβi = 1,2…13 where β and b are constants and are dependent on location and gender, and ai is a constant highly correlated with foot tissue stiffness.The relationship between the sensory intensity to pressure magnitude appears to follow a modified Stevens' power law with power exponents less than 1.0 and consistent across the 13 test locations with a mean of 0.82 and a range from 0.67 to 0.98. This particular model helps to understand the sensation of pressure threshold and its impact in the design of consumer products.

Relationship between perceived and actual frequency represented by common rating scale labels.

Two experiments investigated the relationship between subjective interpretation of frequency terms and corresponding objective values. Evidence supported the existence of a nonlinear relationship that is well described by a logarithmic function. The general form of this relationship was consistent across different methods of eliciting subjective frequency estimates and different frequency response scales. These findings, in combination with prior research, suggest that individuals can be highly accurate in reporting the frequency of prior experiences but that subjective reports using common frequency response scales and scoring methods should not be taken to reflect equal intervals of actual frequency. This bears similarity to psychophysical relationships observed between sensation and stimulus intensity, and it has implications for the interpretation and analysis of self-report measures that use Likert-type frequency response scales.

Improving Interactions between a Power-Assist Robot System and Its Human User in Horizontal Transfer of Objects Using a Novel Adaptive Control Method

Power assist systems are usually used for rehabilitation, healthcare, and so forth.This paper puts emphasis on the use of power assist systems for object transfer and thus brings a novelty in the power-assist applications. However, the interactions between the systems and the human users are usually not satisfactory because human features are not included in the control design. In this paper, we present the development of a 1-DOF power assist system for horizontal transfer of objects. We included human features such as weight perception in the system dynamics and control. We then simulated the system using MATLAB/Simulink for transferring objects with it and (i) determined the optimum maneuverability conditions for object transfer, (ii) determined psychophysical relationships between actual and perceived weights, and (iii) analyzed load forces and motion features. We then used the findings to design a novel adaptive control scheme to improve the interactions between the user and the system. We implemented the novel control (simulated the system again using the novel control), the subjects evaluated the system, and the results showed that the novel control reduced the excessive load forces and accelerations and thus improved the human-system interactions in terms of maneuverability, safety, and so forth. Finally, we proposed to use the findings to develop power assist systems for manipulating heavy objects in industries that may improve interactions between the systems and the users.

Estimating and Validating Relationships between Actual and Perceived Weights for Lifting Objects with a Power Assist Robot: The Psychophysical Approach

A power assist robot reduces the perceived weights of objects lifted with it. However, the relationships between actual and perceived weights have not been estimated yet that result in inappropriate force programming, improper interactions between robots and human users in terms of safety, maneuverability, motion etc. In this paper, we present the development of a power assist robot system for lifting objects. We estimated relationships between actual and perceived weights for the objects lifted with the system by comparing the perceived weights of the power-assist-lifted objects to some reference weights following psychophysics. The results showed that the perceived weights were 40% of the actual weights. However, the power-assist-lifted objects were constrained objects as they were tied to the force sensor and the objects for reference weights were unconstrained objects, which might affect the accuracy and reliability of the relationships. This is why, we conducted another experiment where we made two objects with identical appearance. One was lifted by humans in constrained condition, and another was lifted in unconstrained condition, and weight perception between the two conditions was compared. The results showed that weight perception for constrained lifting was not much different from that for unconstrained lifting. Results of this experiment validated the psychophysical relationships between actual and perceived weights for the power-assistlifted objects, and also confirmed the accuracy of the relationships. Finally, we proposed to use the findings to develop power assist robots for manipulating heavy objects in industries that would improve interactions between robots and their users.

Distinctions in Weight Perception between Constrained and Unconstrained Lifting of Objects

We made two objects (hollow metal cylinders) with identical appearance. One was called the constrained object; another was called the unconstrained object. Human subjects lifted the constrained and unconstrained objects separately for various experiment conditions. We compared human’s weight perception between the two types of objects. Results showed that weight perception between constrained and unconstrained lifting was almost the same. In our previous research, we developed a power assist system for lifting objects and determined a psychophysical relationship between actual and perceived weights for the objects lifted with the system [1]. The perceived weights were 40% of actual weights. However, the objects lifted with the system were constrained objects (as they were tied to the force sensor) that might affect the accuracy of the relationship. The results of this paper confirm that the constraint does not affect weight perception too much, which reconfirms that the psychophysical relationship between actual and perceived weights derived in our previous research was correct [1].

Lowering Objects with a Power Assist Robot: The Preliminary Study

We developed a 1-DOF power assist robot to lower objects from higher position to lower position. Subjects lowered objects of different sizes with the robot and we analyzed heaviness perception, load force, motions (displacement, velocity, acceleration) etc. We determined a psychophysical relationship between actual heaviness and perceived heaviness for objects lowered with the robot system. We tried to identify some control parameters from the analytical results, and proposed them to be used to determine and develop an appropriate control scheme for power assist robots for lowering heavy objects in various industries. This paper reports the preliminary study results on this issue.

Center of Pressure Variations in High-Heeled Shoes

The way in which a person’s foot contacts a shoe surface can have short-term and long-term effects on the whole body. Most previous research on footwear has been carried out using commercially available shoes, and as a result the surface of the shoe with which the foot interacts has not been systematically investigated. A recent invention has allowed the design parameters of a shoe to be investigated. The wedge angle and midfoot conditions were varied, and their effects were modeled with psychophysical relationships. The results show that perceived feelings are closely related to the location of the center of pressure.

Towards developing a human-friendly power assist robot for manipulating heavy objects: special focus on manoeuvrability and object's surface friction

A power assist robot system was developed for manipulating objects in cooperation with human. Weight perception was included in robot dynamics and control. The robot was simulated for different conditions. Optimum manoeuvrability conditions for vertical lifting and horizontal manipulation of objects were determined. Psychophysical relationships between actual and perceived weights were determined, and load forces and motion features were analysed for unimanual and bimanual lifting of objects. Then a novel control scheme was implemented that reduced the excessive load forces and accelerations, and thus improved the system performances for unimanual and bimanual lifts. Motions were also analysed for lowering objects with the robot. A feed-forward friction model was introduced that addressed the effects of friction between human’s hand and object’s surfaces on weight perception and load force. The findings can be used to develop human-friendly power assist robots for manipulating heavy objects in industries.

Weight-Perception-Based Model of Power Assist System for Lifting Objects

This paper deals with the design and control of a power assist system for lifting objects based on weight perception. We considered vertical lifting force (load force) as the desired dynamics for lifting objects with the power assist system. Load force consists of inertial force and gravitational force. We hypothesized that weight perception due to inertial force may differ from perceived weight due to gravitational force for lifting objects with a power assist system. Based on this hypothesis, we designed a 1-degree-of-freedom (DOF) (vertical up-down) power assist system and determined a psychophysical relationship between actual weights and power-assisted weights for lifted objects. We also determined the excess in the load forces that subjects applied when lifting objects with the system. The excessive load force causes problems such as sudden high acceleration of the lifted object, user safety and other concerns while lifting the object, loss of system maneuverability and stability, and possibly fatal accidents. We modified the power-assist control based on the psychophysical relationship and the load force characteristics. Modifying control reduced the excess in load forces and significantly enhanced maneuverability, naturalness, ease of use, stability, and safety. We proposed using the findings to design industrial power assist systems for transporting heavy objects in various industries such as assembly and manufacturing, mining, logistics and transport, construction, disaster management and rescue, and military operations.