Author: Lo, Shuk-man
Title: Responses to thermal stimulation in persons with central poststroke pain : sensory decision theory analysis
Degree: M.Sc.
Year: 2006
Subject: Hong Kong Polytechnic University -- Dissertations.
Cerebrovascular disease -- Patients -- Rehabilitation.
Chronic pain.
Sensory stimulation.
Department: School of Nursing
Pages: xi, 107 leaves : ill. ; 30 cm.
Language: English
Abstract: Purpose The purpose of this study is to determine characteristics of pain responses in persons with central poststroke pain (CPSP) using the sensory decision theory (SDT) and measures of heart rate variability (HRV). Method A single interval forced-choice SDT procedure was administered to test seven subjects with CPSP and 15 normal subjects for responses to thermal stimulation. Forty-eight stimuli of 6 thermal intensities of 36 oC, 39 oC, 42 oC, 45 oC, 47 oC and 49 oC were delivered. Neurosensory functioning was measured by discriminability [P(A)], and affective component of pain was evaluated by report criterion (B); whereas, autonomic response to thermal stimuli was evaluated by using time domain and frequency domain parameters of HRV. Results The results showed that there were no significance difference between the two groups in discriminability and report criterion. However, the CPSP group had lower discriminability in high intensity block in comparing with the normal subjects. Alternatively, higher report criterion in high intensity block was found in the CPSP group. Subjects with CPSP were relatively more stoical. Baseline measures of HRV did not show significant difference between the 2 groups. Greater parasympathetic dominance was indicated by LF/HF ratio in the CPSP group. A continuous decrease in LF/HF ratio existed in both groups throughout the procedure. In the post-procedure phase, there was a significant difference in SDNN as indicated by spectral analysis. In the control group, a moderate association between discriminability in high intensity block, mean HR and mean NN appeared. Correlation between discriminability in low intensity block and total power was fair. Conversely, a strong correlation between the report criterion in low intensity block and LF/HF ratio was noted in the CPSP group. Discussion The CPSP subjects having lower discriminability was a fact indicating damage to the neural network, and they were relatively more stoical to report pain without the influence of affective stress by the effect of the experiment. Possible reason for the significant change in SDNN after the procedure was related to correlation with existing anxious state to mean HR, mean NN and LF/HF ratio in this group. The moderate correlation having in the control group between discriminability to mean HR and mean NN may be due to aging. Other correlations in the CPSP group remained controversy in explanation. Conclusion The insignificant results from the SDT measures yielding inadequate scientific evidence and inconsistent directional change in the time domain and frequency domain parameters appearing in each group in each experimental phase bringing controversy matters made findings impossible to link the sensory, affective and autonomic responses for characterization of pain pattern in CPSP. Further study into these matters is needed.
Rights: All rights reserved
Access: restricted access

Files in This Item:
File Description SizeFormat 
b19736484.pdfFor All Users (off-campus access for PolyU Staff & Students only)9.34 MBAdobe PDFView/Open


Copyright Undertaking

As a bona fide Library user, I declare that:

  1. I will abide by the rules and legal ordinances governing copyright regarding the use of the Database.
  2. I will use the Database for the purpose of my research or private study only and not for circulation or further reproduction or any other purpose.
  3. I agree to indemnify and hold the University harmless from and against any loss, damage, cost, liability or expenses arising from copyright infringement or unauthorized usage.

By downloading any item(s) listed above, you acknowledge that you have read and understood the copyright undertaking as stated above, and agree to be bound by all of its terms.

Show full item record

Please use this identifier to cite or link to this item: https://theses.lib.polyu.edu.hk/handle/200/3409