1
|
Sadeghlo N, Selvanathan J, Koshkebaghi D, Cioffi I. Aberrant occlusal sensitivity in adults with increased somatosensory amplification: a case-control study. Clin Oral Investig 2024; 28:250. [PMID: 38613726 DOI: 10.1007/s00784-024-05628-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2024] [Accepted: 03/20/2024] [Indexed: 04/15/2024]
Abstract
OBJECTIVES Occlusal sensitivity (OS)-the ability to detect fine objects between opposing teeth-mainly relies on the activity of mechanoreceptors located in the periodontal ligament. We tested whether somatosensory amplification (SSA)-the tendency to perceive normal somatic sensations as being intense, noxious, and disturbing, which plays a critical role in hypervigilance-affects OS. MATERIALS AND METHODS We measured OS in 66 adults divided into three groups based on their SSA scores (LowSSA, Intermediate - IntSSA, HighSSA) by asking them to bite on aluminum foils (8 to 72 μm thick) and a sham foil, and report whether they felt each foil. We performed 20 trials for each thickness and sham condition (each participant was tested 120 times), and compared the frequency of correct answers (%correct) among groups after adjusting for participants' trait anxiety, depression, self-reported oral behaviors, and masseter cross-sectional area. RESULTS %correct was affected by the interaction Foil Thickness-by-SSA (p = 0.007). When tested with the 8 μm foil, the HighSSA group had a lower %correct than the IntSSA (contrast estimate [95% CI]: -14.2 [-25.8 - -2.6]; p = 0.012) and the LowSSA groups (-19.1 [-31.5 - -6.6]; p = 0.001). Similarly, with the 24 μm foil, the HighSSA group had a lower %correct compared to the IntSSA (-12.4 [-24.8-0.1]; p = 0.048) and the LowSSA groups (-10.8 [-22.5-0.8]; p = 0.073). CONCLUSION Individuals with high SSA present with an aberrant occlusal sensitivity. CLINICAL RELEVANCE Our findings provide novel insights into the relationship between occlusal perception and psychological factors, which may influence an individual's ability to adapt to dental work.
Collapse
Affiliation(s)
- Negin Sadeghlo
- Faculty of Dentistry, Centre for Multimodal Sensorimotor and Pain Research, University of Toronto, 124 Edward Street, Toronto, ON, M5G 1X3, Canada
| | - Janannii Selvanathan
- Faculty of Dentistry, Centre for Multimodal Sensorimotor and Pain Research, University of Toronto, 124 Edward Street, Toronto, ON, M5G 1X3, Canada
| | - Dursa Koshkebaghi
- Faculty of Dentistry, Centre for Multimodal Sensorimotor and Pain Research, University of Toronto, 124 Edward Street, Toronto, ON, M5G 1X3, Canada
| | - Iacopo Cioffi
- Faculty of Dentistry, Centre for Multimodal Sensorimotor and Pain Research, University of Toronto, 124 Edward Street, Toronto, ON, M5G 1X3, Canada.
| |
Collapse
|
2
|
Devecioğlu İ, Karakulak E. Three Sliding Probes Placed on Forelimb Skin for Proprioceptive Feedback Differentially yet Complementarily Contribute to Hand Gesture Detection and Object-Size Discrimination. Ann Biomed Eng 2024; 52:982-996. [PMID: 38246964 PMCID: PMC10940487 DOI: 10.1007/s10439-023-03434-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2023] [Accepted: 12/22/2023] [Indexed: 01/23/2024]
Abstract
The purpose was to assess the effectiveness of three sliding tactile probes placed on the forelimb skin to provide proprioceptive feedback for the detection of hand gestures and discrimination of object size. Tactile contactors representing the first three fingers were driven along the proximodistal axis by linear servo motors. Twenty healthy subjects were involved in the gesture detection test, with 10 of them also participating in the object-size discrimination task. Motors were controlled by computer in the first four sessions of the gesture detection experiment, while the fifth session utilized a sensorized glove. Both the volar and dorsal sides of the forearm were examined. In the object-size discrimination experiment, the method was exclusively assessed on the volar surface under four distinct feedback conditions, including all fingers and each finger separately. The psychophysical data were further analyzed using a structural equation model (SEM) to evaluate the specific contributions of each individual contactor. Subjects consistently outperformed the chance level in detecting gestures. Performance improved up to the third session, with better results obtained on the volar side. The performances were similar in the fourth and fifth sessions. The just noticeable difference for achieving a 75% discrimination accuracy was found to be 2.90 mm of movement on the skin. SEM analysis indicated that the contactor for the index finger had the lowest importance in gesture detection, while it played a more significant role in object-size discrimination. However, all fingers were found to be significant predictors of subjects' responses in both experiments, except for the thumb, which was deemed insignificant in object-size discrimination. The study highlights the importance of considering the partial contribution of each degree of freedom in a sensory feedback system, especially concerning the task, when designing such systems.
Collapse
Affiliation(s)
- İsmail Devecioğlu
- Biomedical Engineering Department, Çorlu Faculty of Engineering, Tekirdağ Namık Kemal University, Tekirdağ, Turkey.
| | - Ertuğrul Karakulak
- Department of Biomedical Device Technologies, Vocational School of Technical Sciences, Tekirdağ Namık Kemal University, Tekirdağ, Turkey
| |
Collapse
|
3
|
Sarak Kucukosmanoglu H, Coskun G, Yosmaoglu HB. The Effect of Yoga Practice on Cervical Tactile Acuity and Body Awareness. Percept Mot Skills 2023; 130:2031-2046. [PMID: 37395628 DOI: 10.1177/00315125231187435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/04/2023]
Abstract
Body-mind-based holistic methods of relaxation and improved well-being, such as yoga and meditation, improve body awareness and have often been used to enhance quality of life and the ability to cope with pain. We aimed to compare tactile sensory acuity and body awareness in healthy sedentary individuals who practiced yoga regularly and in control participants who had not practiced yoga. Participants were 60 individuals, aged between 18 and 35 years who were divided into two groups according to whether they had previously practiced yoga. We used the two-point discrimination (TPD) test to determine participants' tactile acuity, as measured with a digital calliper at the C7, C5, C3, C1 and T1 spinal segments and with the Body Awareness Questionnaire (BAQ). The TPD measurements of individuals who practiced yoga and meditation had a lower discriminatory threshold compared to those who had not practiced yoga (p < .001), and the self-reported BAQ score of yoga practitioners was higher than that of the controls (p < .001). We found a positive correlation between the length of the prior duration of yoga experience and self-reported body awareness (r = .567, p < .001). There was a significant negative correlation (r = -.379, p = .015) between the C5 segment and the TPD measurements, but not for the other cervical spinal segments (p > .05). There was a negative correlation between the length of prior yoga practice and the TPD measurements in all cervical segments (p < .001). The most negative correlation was found at the C7 segment (r = -.844, p < .001) and the least negative correlation was found at the C3 segment (r = -.669, p < .001). These data suggest that yoga and meditation practices may improve well-being and diminish pain by increasing body awareness and tactile sensory acuity in the cervical region.
Collapse
Affiliation(s)
| | - Gursoy Coskun
- Hacettepe University Faculty of Physiotherapy and Rehabilitation, Ankara Turkey
| | - Hayri Baran Yosmaoglu
- Department of Physical Therapy and Rehabilitation, Faculty of Health Sciences, Baskent University, Ankara, Turkey
| |
Collapse
|
4
|
Apparent increase in lip size influences two-point discrimination. Sci Rep 2023; 13:3082. [PMID: 36813847 PMCID: PMC9947174 DOI: 10.1038/s41598-023-30067-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Accepted: 02/15/2023] [Indexed: 02/24/2023] Open
Abstract
Magnified vision of one's body part has been shown to improve tactile discrimination. We used an anesthetic cream (AC) to determine if somesthetic stimulation that alters the perception of the size of one's body would also improve two point-discrimination (2PD). In Experiment 1, application of AC caused an increase in perceived lip size and an improvement in a 2PD. As perceived lip size increased, subjects became more accurate in identifying that they had been touched in two locations. Experiment 2 confirmed this effect in a larger sample and introduced a control condition (no AC) that demonstrated that the change in performance was not attributable to practice or familiarity with the task. In Experiment 3, we showed that both AC and moisturizing cream improved subjects' ability to indicate that they had been touched in 2 locations, but the improvement was modulated by perceived lip size only for AC. These results support the idea that changes in the body representation influence 2PD.
Collapse
|
5
|
Schaefer M, Kevekordes MC, Sommer H, Gärtner M. Of Orchids and Dandelions: Empathy but Not Sensory Processing Sensitivity Is Associated with Tactile Discrimination Abilities. Brain Sci 2022; 12:brainsci12050641. [PMID: 35625027 PMCID: PMC9140078 DOI: 10.3390/brainsci12050641] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Revised: 04/06/2022] [Accepted: 04/09/2022] [Indexed: 11/16/2022] Open
Abstract
Many concepts of the human personality are based on assumptions about underlying physiological processes. The most prominent example is probably the concept of extraversion introduced by H.J. Eysenck decades ago. However, more recent approaches also propose that personality traits may be reflected by physiological processes. For example, empathic personality dimensions have been linked to tactile perception, suggesting that individuals with higher tactile sensitivity are also more empathetic to the sensations of others. Another recent example is the concept of sensory processing sensitivity, which has been linked to enhanced primary sensory processing. However, the exact relationship between tactile abilities and personality is still unclear, thus the current study aims to test whether different personality dimensions affect the performance in a tactile acuity task. Tactile abilities of healthy participants were tested with tactile 2-point-thresholds on the hands. Personality dimensions were examined with respect to empathy, sensory processing sensitivity, and the Big Five. Results revealed that empathy, but not sensory processing sensitivity, was associated with tactile performance. We conclude that the ability to feel with someone else seems to be linked to the perception of our own body. Thus, the sense of touch may play an important role for empathy. We discuss explanations of these results and highlight possible implications of our findings.
Collapse
Affiliation(s)
- Michael Schaefer
- Correspondence: ; Tel.: +49-(0)-30-6117542; Fax: +49-(0)-30-6715233
| | | | | | | |
Collapse
|
6
|
Dispositional empathy predicts primary somatosensory cortex activity while receiving touch by a hand. Sci Rep 2021; 11:11294. [PMID: 34050215 PMCID: PMC8163792 DOI: 10.1038/s41598-021-90344-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2020] [Accepted: 05/06/2021] [Indexed: 12/14/2022] Open
Abstract
Previous research revealed an active network of brain areas such as insula and anterior cingulate cortex when witnessing somebody else in pain and feeling empathy. But numerous studies also suggested a role of the somatosensory cortices for state and trait empathy. While recent studies highlight the role of the observer’s primary somatosensory cortex when seeing painful or nonpainful touch, the interaction of somatosensory cortex activity with empathy when receiving touch on the own body is unknown. The current study examines the relationship of touch related somatosensory cortex activity with dispositional empathy by employing an fMRI approach. Participants were touched on the palm of the hand either by the hand of an experimenter or by a rubber hand. We found that the BOLD responses in the primary somatosensory cortex were associated with empathy personality traits personal distress and perspective taking. This relationship was observed when participants were touched both with the experimenter’s real hand or a rubber hand. What is the reason for this link between touch perception and trait empathy? We argue that more empathic individuals may express stronger attention both to other’s human perceptions as well as to the own sensations. In this way, higher dispositional empathy levels might enhance tactile processing by top-down processes. We discuss possible implications of these findings.
Collapse
|
7
|
Foo KY, Kennedy KM, Zilkens R, Allen WM, Fang Q, Sanderson RW, Anstie J, Dessauvagie BF, Latham B, Saunders CM, Chin L, Kennedy BF. Optical palpation for tumor margin assessment in breast-conserving surgery. BIOMEDICAL OPTICS EXPRESS 2021; 12:1666-1682. [PMID: 33796380 PMCID: PMC7984801 DOI: 10.1364/boe.415888] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/24/2020] [Revised: 01/22/2021] [Accepted: 01/25/2021] [Indexed: 06/12/2023]
Abstract
Intraoperative margin assessment is needed to reduce the re-excision rate of breast-conserving surgery. One possibility is optical palpation, a tactile imaging technique that maps stress (force applied across the tissue surface) as an indicator of tissue stiffness. Images (optical palpograms) are generated by compressing a transparent silicone layer on the tissue and measuring the layer deformation using optical coherence tomography (OCT). This paper reports, for the first time, the diagnostic accuracy of optical palpation in identifying tumor within 1 mm of the excised specimen boundary using an automated classifier. Optical palpograms from 154 regions of interest (ROIs) from 71 excised tumor specimens were obtained. An automated classifier was constructed to predict the ROI margin status by first choosing a circle diameter, then searching for a location within the ROI where the circle was ≥ 75% filled with high stress (indicating a positive margin). A range of circle diameters and stress thresholds, as well as the impact of filtering out non-dense tissue regions, were tested. Sensitivity and specificity were calculated by comparing the automated classifier results with the true margin status, determined from co-registered histology. 83.3% sensitivity and 86.2% specificity were achieved, compared to 69.0% sensitivity and 79.0% specificity obtained with OCT alone on the same dataset using human readers. Representative optical palpograms show that positive margins containing a range of cancer types tend to exhibit higher stress compared to negative margins. These results demonstrate the potential of optical palpation for margin assessment.
Collapse
Affiliation(s)
- Ken Y. Foo
- BRITElab, Harry Perkins Institute of Medical Research, QEII Medical Centre, Nedlands, Australia
- The University of Western Australia, Perth, Australia
- Department of Electrical, Electronic and Computer Engineering, School of Engineering, The University of Western Australia, Perth, Australia
| | - Kelsey M. Kennedy
- BRITElab, Harry Perkins Institute of Medical Research, QEII Medical Centre, Nedlands, Australia
- The University of Western Australia, Perth, Australia
| | - Renate Zilkens
- BRITElab, Harry Perkins Institute of Medical Research, QEII Medical Centre, Nedlands, Australia
- The University of Western Australia, Perth, Australia
- School of Medicine, The University of Western Australia, Perth, Australia
| | - Wes M. Allen
- BRITElab, Harry Perkins Institute of Medical Research, QEII Medical Centre, Nedlands, Australia
- The University of Western Australia, Perth, Australia
- Department of Electrical, Electronic and Computer Engineering, School of Engineering, The University of Western Australia, Perth, Australia
| | - Qi Fang
- BRITElab, Harry Perkins Institute of Medical Research, QEII Medical Centre, Nedlands, Australia
- The University of Western Australia, Perth, Australia
- Department of Electrical, Electronic and Computer Engineering, School of Engineering, The University of Western Australia, Perth, Australia
| | - Rowan W. Sanderson
- BRITElab, Harry Perkins Institute of Medical Research, QEII Medical Centre, Nedlands, Australia
- The University of Western Australia, Perth, Australia
- Department of Electrical, Electronic and Computer Engineering, School of Engineering, The University of Western Australia, Perth, Australia
| | - James Anstie
- BRITElab, Harry Perkins Institute of Medical Research, QEII Medical Centre, Nedlands, Australia
- The University of Western Australia, Perth, Australia
- Department of Electrical, Electronic and Computer Engineering, School of Engineering, The University of Western Australia, Perth, Australia
| | - Benjamin F. Dessauvagie
- School of Medicine, The University of Western Australia, Perth, Australia
- PathWest, Fiona Stanley Hospital, Murdoch, Australia
| | - Bruce Latham
- PathWest, Fiona Stanley Hospital, Murdoch, Australia
- School of Medicine, University of Notre Dame, Fremantle, Australia
| | - Christobel M. Saunders
- School of Medicine, The University of Western Australia, Perth, Australia
- Breast Centre, Fiona Stanley Hospital, Murdoch, Australia
- Breast Clinic, Royal Perth Hospital, Perth, Australia
| | - Lixin Chin
- BRITElab, Harry Perkins Institute of Medical Research, QEII Medical Centre, Nedlands, Australia
- The University of Western Australia, Perth, Australia
- Department of Electrical, Electronic and Computer Engineering, School of Engineering, The University of Western Australia, Perth, Australia
| | - Brendan F. Kennedy
- BRITElab, Harry Perkins Institute of Medical Research, QEII Medical Centre, Nedlands, Australia
- The University of Western Australia, Perth, Australia
- Department of Electrical, Electronic and Computer Engineering, School of Engineering, The University of Western Australia, Perth, Australia
- Australian Research Council Centre for Personalised Therapeutics Technologies, Perth, Australia
| |
Collapse
|
8
|
Schaefer M, Joch M, Rother N. Feeling Touched: Empathy Is Associated With Performance in a Tactile Acuity Task. Front Hum Neurosci 2021; 15:593425. [PMID: 33633552 PMCID: PMC7900490 DOI: 10.3389/fnhum.2021.593425] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Accepted: 01/12/2021] [Indexed: 12/30/2022] Open
Abstract
The concept of empathy describes our capacity to understand the emotions and intentions of others and to relate to our conspecifics. Numerous studies investigated empathy as a state as well as a stable personality trait. For example, recent studies in neuroscience suggest, among other brain areas such as the insula or the ACC, a role of the somatosensory cortices for empathy (e.g., when observing someone else being touched). Since the classic understanding of the primary somatosensory cortex is to represent touch on the body surface, we here aimed to test whether tactile performance is linked to the personality trait empathy. To test this, we examined the tactile acuity of 95 healthy participants (mean age 31 years) by using a two-point discrimination threshold task at the index fingers. Trait empathy was assessed by employing the interpersonal reactivity index (IRI), which measures self-reported empathy with four scales (empathic concern, perspective taking, fantasy, and personal distress). Results of regression analyses suggested the subscale empathic concern to be positively associated with performance in the tactile acuity task. We discuss this finding in the light of recent studies on empathy and consider possible implications of tactile training to enhance empathy.
Collapse
Affiliation(s)
- Michael Schaefer
- Department Naturwissenschaften, Medical School Berlin, Berlin, Germany
| | - Marcel Joch
- Department Naturwissenschaften, Medical School Berlin, Berlin, Germany
| | - Nikolas Rother
- Department Naturwissenschaften, Medical School Berlin, Berlin, Germany
| |
Collapse
|
9
|
Treves IN, Tello LY, Davidson RJ, Goldberg SB. The relationship between mindfulness and objective measures of body awareness: A meta-analysis. Sci Rep 2019; 9:17386. [PMID: 31758073 PMCID: PMC6874545 DOI: 10.1038/s41598-019-53978-6] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2019] [Accepted: 10/29/2019] [Indexed: 01/10/2023] Open
Abstract
Although awareness of bodily sensations is a common mindfulness meditation technique, studies assessing the relationship between mindfulness and body awareness have provided mixed results. The current study sought to meta-analytically examine the relationship between mindfulness operationalized as a dispositional trait or a construct trained through short- (i.e., randomized controlled trials [RCTs]) or long-term mindfulness meditation practice with objective measures of body awareness accuracy. PubMed, Web of Science, PsycINFO, and Scopus were searched. Studies were eligible if they reported the association between mindfulness and body awareness, were published in English, and included adults. Across 15 studies (17 independent samples), a small effect was found linking mindfulness with greater body awareness accuracy (g = 0.21 [0.08, 0.34], N = 879). When separated by study design, only RCTs continued to show a significant relationship (g = 0.20, [0.02, 0.38], k = 7, n = 505). Heterogeneity of effects was low (I2 < 25%), although with wide confidence intervals. Effects were not moderated by study quality. Low fail-safe N estimates reduce confidence in the observed effects. Results suggest a small but potentially detectable relationship between mindfulness and body awareness accuracy. Future investigations could examine individual differences in body awareness as a mechanism within mindfulness interventions.
Collapse
Affiliation(s)
- Isaac N Treves
- Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, Massachusetts, USA
| | - Lawrence Y Tello
- School of Public Health, University of California - Berkeley, Berkeley, CA, 94720, USA
| | - Richard J Davidson
- Center for Healthy Minds, University of Wisconsin - Madison, Madison, WI, 53703, USA.,Department of Psychology, University of Wisconsin - Madison, Madison, WI, 53706, USA
| | - Simon B Goldberg
- Center for Healthy Minds, University of Wisconsin - Madison, Madison, WI, 53703, USA. .,Department of Counseling Psychology, University of Wisconsin - Madison, Madison, WI, 53706, USA.
| |
Collapse
|
10
|
Allen WM, Wijesinghe P, Dessauvagie BF, Latham B, Saunders CM, Kennedy BF. Optical palpation for the visualization of tumor in human breast tissue. JOURNAL OF BIOPHOTONICS 2019; 12:e201800180. [PMID: 30054979 DOI: 10.1002/jbio.201800180] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Revised: 07/20/2018] [Accepted: 07/26/2018] [Indexed: 05/17/2023]
Abstract
Accurate and effective removal of tumor in one operation is an important goal of breast-conserving surgery. However, it is not always achieved. Surgeons often utilize manual palpation to assess the surgical margin and/or the breast cavity. Manual palpation, however, is subjective and has relatively low resolution. Here, we investigate a tactile imaging technique, optical palpation, for the visualization of tumor. Optical palpation generates maps of the stress at the surface of tissue under static preload compression. Stress is evaluated by measuring the deformation of a contacting thin compliant layer with known mechanical properties using optical coherence tomography. In this study, optical palpation is performed on 34 freshly excised human breast specimens. Wide field-of-view (up to ~46 × 46 mm) stress images, optical palpograms, are presented from four representative specimens, demonstrating the capability of optical palpation to visualize tumor. Median stress reported for adipose tissue, 4 kPa, and benign dense tissue, 8 kPa, is significantly lower than for invasive tumor, 60 kPa. In addition, we demonstrate that optical palpation provides contrast consistent with a related optical technique, quantitative micro-elastography. This study demonstrates that optical palpation holds promise for visualization of tumor in breast-conserving surgery.
Collapse
Affiliation(s)
- Wes M Allen
- BRITElab, Harry Perkins Institute of Medical Research, QEII Medical Centre, Nedlands and Centre for Medical Research, The University of Western Australia, Perth, Western Australia, Australia
- Department of Electrical, Electronic & Computer Engineering, School of Engineering, The University of Western Australia, Perth, Western Australia, Australia
| | - Philip Wijesinghe
- BRITElab, Harry Perkins Institute of Medical Research, QEII Medical Centre, Nedlands and Centre for Medical Research, The University of Western Australia, Perth, Western Australia, Australia
- Department of Electrical, Electronic & Computer Engineering, School of Engineering, The University of Western Australia, Perth, Western Australia, Australia
| | - Benjamin F Dessauvagie
- PathWest, Fiona Stanley Hospital, Murdoch, Western Australia, Australia
- Division of Pathology and Laboratory Medicine, Medical School, The University of Western Australia, Perth, Western Australia, Australia
| | - Bruce Latham
- PathWest, Fiona Stanley Hospital, Murdoch, Western Australia, Australia
| | - Christobel M Saunders
- Division of Surgery, Medical School, The University of Western Australia, Perth, Western Australia, Australia
- Breast Centre, Fiona Stanley Hospital, Murdoch, Western Australia, Australia
- Breast Clinic, Royal Perth Hospital, Perth, Western Australia, Australia
| | - Brendan F Kennedy
- BRITElab, Harry Perkins Institute of Medical Research, QEII Medical Centre, Nedlands and Centre for Medical Research, The University of Western Australia, Perth, Western Australia, Australia
- Department of Electrical, Electronic & Computer Engineering, School of Engineering, The University of Western Australia, Perth, Western Australia, Australia
| |
Collapse
|
11
|
Fiorio M, Emadi Andani M, Recchia S, Tinazzi M. The somatosensory temporal discrimination threshold changes after a placebo procedure. Exp Brain Res 2018; 236:2983-2990. [DOI: 10.1007/s00221-018-5357-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Accepted: 08/10/2018] [Indexed: 10/28/2022]
|
12
|
Abstract
NMDA-dependent Hebbian learning drives neuronal plasticity in different cortical areas, and across species. In the primary somatosensory cortex (S-I), Hebbian learning is induced via the persistent low-rate afferent stimulation of a small area of skin. In particular, plasticity is induced in superficial cortical layers II/III of the S-I cortex that represents the stimulated area of skin. Here, we used the model system of NMDA-dependent Hebbian learning to investigate the influence of non-afferent (visual) input on Hebbian plasticity in S-I. We induced Hebbian learning in 48 participants by applying 3 hours of tactile coactivation to the right index fingertip via small loudspeaker membranes. During coactivation, different groups viewed either touches to individual fingers, which is known to activate S-I receptive fields, touches to an object, which should not activate S-I receptive fields, or no touch at all. Our results show that coactivation significantly lowers tactile spatial discrimination thresholds at the stimulated finger post- versus pre-training across groups. However, we did not find evidence for a significant modulatory effect of visual condition on tactile spatial discrimination performance. This suggests that non-afferent (visual) signals do not interact with Hebbian learning in superficial cortical layers of S-I, but may integrate into deeper cortical layers instead.
Collapse
|