Tactile roughness discrimination threshold is unrelated to tactile spatial acuity

AbstractThe aim of this study is to investigate whether or not spatial congruency between tactile and auditory stimuli would influence the tactile roughness discrimination of stimuli presented to the fingers or cheeks. In the experiment, when abrasive films were passively presented to the participants, white noise bursts were simultaneously presented from the same or different side, either near or far from the head. The results showed that when white noise was presented from the same side as the tactile stimuli, especially from near the head, the discrimination sensitivity on the cheeks was higher than when sound was absent or presented from a different side. A similar pattern was observed in discrimination by the fingers but it was not significant. The roughness discrimination by the fingers was also influenced by the presentation of sound close to the head, but significant differences between conditions with and without sounds were observed at the decisional level. Thus, the spatial congruency between tactile and auditory information selectively modulated the roughness sensitivity of the skin on the cheek, especially when the sound source was close to the head.

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Recurrence quantification analysis of EEG signals for tactile roughness discrimination

International Journal of Machine Learning and Cybernetics ◽

10.1007/s13042-020-01224-1 ◽

2020 ◽

Author(s):

Golnaz Baghdadi ◽

Mahmood Amiri ◽

Egidio Falotico ◽

Cecilia Laschi

Keyword(s):

Recurrence Quantification Analysis ◽

Eeg Signals ◽

Recurrence Quantification ◽

Quantification Analysis ◽

Tactile Roughness ◽

Roughness Discrimination

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The neural code for tactile roughness in the somatosensory nerves

Journal of Neurophysiology ◽

10.1152/jn.00374.2017 ◽

2017 ◽

Vol 118 (6) ◽

pp. 3107-3117 ◽

Cited By ~ 14

Author(s):

Justin D. Lieber ◽

Xinyue Xia ◽

Alison I. Weber ◽

Sliman J. Bensmaia

Keyword(s):

Fiber Type ◽

Rhesus Macaques ◽

Discrimination Performance ◽

Nerve Fibers ◽

Neural Code ◽

Population Response ◽

Perceptual Dimension ◽

Tactile Roughness ◽

Roughness Discrimination ◽

Sense Of Touch

Roughness is the most salient perceptual dimension of surface texture but has no well-defined physical basis. We seek to determine the neural determinants of tactile roughness in the somatosensory nerves. Specifically, we record the patterns of activation evoked in tactile nerve fibers of anesthetized Rhesus macaques to a large and diverse set of natural textures and assess what aspect of these patterns of activation can account for psychophysical judgments of roughness, obtained from human observers. We show that perceived roughness is determined by the variation in the population response, weighted by fiber type. That is, a surface will feel rough to the extent that the activity varies across nerve fibers and varies across time within nerve fibers. We show that this variation-based neural code can account not only for magnitude estimates of roughness but also for roughness discrimination performance. NEW & NOTEWORTHY Our sense of touch endows us with an exquisite sensitivity to the microstructure of surfaces, the most salient aspect of which is roughness. We analyze the responses evoked in tactile fibers of monkeys by natural textures and compare them to judgments of roughness obtained for the same textures from human observers. We then describe how texture signals from three populations of nerve fibers are integrated to culminate in a percept of roughness.

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Physical determinants of the shape of the psychophysical curve relating tactile roughness to raised-dot spacing: implications for neuronal coding of roughness

Journal of Neurophysiology ◽

10.1152/jn.00717.2012 ◽

2013 ◽

Vol 109 (5) ◽

pp. 1403-1415 ◽

Cited By ~ 13

Author(s):

Adrian Sutu ◽

El-Mehdi Meftah ◽

C. Elaine Chapman

Keyword(s):

Psychometric Function ◽

Weber Fraction ◽

Critical Issue ◽

Linear Increase ◽

Spatial Period ◽

Invariant Relation ◽

Monotonic Increase ◽

Neuronal Coding ◽

Tactile Roughness ◽

Roughness Discrimination

There are conflicting reports as to whether the shape of the psychometric relation between perceived roughness and tactile element spacing [spatial period (SP)] follows an inverted U-shape or a monotonic linear increase. This is a critical issue because the former result has been used to assess neuronal codes for roughness. We tested the hypothesis that the relation's shape is critically dependent on tactile element height (raised dots). Subjects rated the roughness of low (0.36 mm)- and high (1.8 mm)-raised-dot surfaces displaced under their fingertip. Inverted U-shaped curves were obtained as the SP of low-dot surfaces was increased (1.3–6.2 mm, tetragonal arrays); a monotonic increase was observed for high-dot surfaces. We hypothesized that roughness is not a single sensory continuum across the tested SPs of low-dot surfaces, predicting that roughness discrimination would show deviations from the invariant relation between threshold (ΔS) and the value of the standard (S) surface (Weber fraction, ΔS/S) expected for a single continuum. The results showed that Weber fractions were increased for SPs on the descending limb of the inverted U-shaped curve. There was also an increase in the Weber fraction for high-dot surfaces but only at the peak (3 mm), corresponding to the SP at which the slope of the psychometric function showed a modest decline. Together the results indicate that tactile roughness is not a continuum across low-dot SPs of 1.3–6.2 mm. These findings suggest that correlating the inverted U-shaped function with neuronal codes is of questionable validity. A simple intensive code may well contribute to tactile roughness.

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Spatial Acuity of the Nociceptive System and Spatial Summation of Pain: Potential Implications for the Clinic

Douleur et Analgésie ◽

10.3166/dea-2021-0170 ◽

2021 ◽

Author(s):

A. Hurth

Keyword(s):

Spatial Summation ◽

Discrimination Threshold ◽

Stimulus Modality ◽

Nociceptive System ◽

Spatial Acuity ◽

Tactile System

Previous studies investigating spatial acuity measured by two-point discrimination threshold concluded that the nociceptive system is less accurate than the innocuous tactile system. In the discussed article, the authors point out that the nociceptive system is more accurate than the tactile system when controlling for the stimulus modality and intensity in healthy pain-free individuals. Furthermore, this article shows that the pattern of distance-based and areabased spatial summation of pain is modality independent.

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Factors affecting tactile spatial acuity

PsycEXTRA Dataset ◽

10.1037/e536982012-196 ◽

1997 ◽

Author(s):

James C. Craig ◽

Jayne M. Kisner

Keyword(s):

Factors Affecting ◽

Spatial Acuity

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Absolute pitch ability is not associated with advantage in musical tension processing

10.31234/osf.io/r6vm8 ◽

2020 ◽

Author(s):

Linshu Zhou ◽

Fang Liu ◽

Tang Hai ◽

Jun Jiang ◽

Dongrui Man ◽

...

Keyword(s):

Detection Threshold ◽

Absolute Pitch ◽

Discrimination Threshold ◽

Pitch Change ◽

Letter Naming ◽

Direction Discrimination ◽

Pitch Direction ◽

Lower Accuracy ◽

Tonal Hierarchy ◽

The Stability

Absolute pitch (AP), a superior ability of pitch letter naming in the absence of a reference note, has long been viewed as an indicator of human musical talent and thus as evidence for the adaptationist hypothesis of music evolution. Little is known, however, whether AP possessors are superior to non-AP possessors in music processing. The present study investigated whether the AP ability facilitates musical tension processing in perceptual and experienced tasks. Twenty-one AP possessors and 21 matched non-AP possessors were tested using novel melodies in C and non-C contexts. Results indicated that the two groups provided comparable ratings of perceived and felt tension for melodies in both contexts. While AP possessors demonstrated lower accuracy with longer reaction time than non-AP possessors in naming movable solfège syllables for pitch in the pretest, their tension rating profiles showed a similar tonal hierarchy as non-AP possessors in regard to the stability of the ending tones of the melodies in both major and minor keys. Correlation analyses suggested that musical tension ratings were not significantly related to performance in pitch letter, movable solfège syllable naming, pitch change detection threshold, or pitch direction discrimination threshold for either group. These findings suggest that pitch naming abilities (either pitch letter or movable solfège syllable naming) do not benefit processing of perceived or felt musical tension, providing evidence to support the hypothesis that AP ability is not associated with advantage in music processing.

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