Faculty Opinions recommendation of Temporal analysis of cortical mechanisms for pain relief by tactile stimuli in humans.

The role of the somatosensory cortices (SI and SII) in pain perception has long been in dispute. Human imaging studies demonstrate activation of SI and SII associated with painful stimuli, but results have been variable, and the functional relevance of any such activation is uncertain. The present study addresses this issue by testing whether the time course of somatosensory activation, evoked by painful heat and nonpainful tactile stimuli, is sufficient to discriminate temporal differences that characterize the perception of these stimulus modalities. Four normal subjects each participated in three functional magnetic resonance imaging (fMRI) sessions, in which painful (noxious heat 45–46°C) and nonpainful test stimuli (brushing at 2 Hz) were applied repeatedly (9-s stimulus duration) to the left leg in separate experiments. Activation maps were generated comparing painful to neutral heat (35°C) and nonpainful brushing to rest. Directed searches were performed in SI and SII for sites reliably activated by noxious heat and brush stimuli, and stimulus-dependent regions of interest (ROI) were then constructed for each subject. The time course, per stimulus cycle, was extracted from these ROIs and compared across subjects, stimulus modalities, and cortical regions. Both innocuous brushing and noxious heat produced significant activation within contralateral SI and SII. The time course of brush-evoked responses revealed a consistent single peak of activity, approximately 10 s after the onset of the stimulus, which rapidly diminished upon stimulus withdrawal. In contrast, the response to heat pain in both SI and SII was characterized by a double-peaked time course in which the maximum response (the 2nd peak) was consistently observed ∼17 s after the onset of the stimulus (8 s following termination of the stimulus). This prolonged period of activation paralleled the perception of increasing pain intensity that persists even after stimulus offset. On the other hand, the temporal profile of the initial minor peak in pain-related activation closely matched that of the brush-evoked activity, suggesting a possible relationship to tactile components of the thermal stimulation procedure. These data indicate that both SI and SII cortices are involved in the processing of nociceptive information and are consistent with a role for these structures in the perception of temporal aspects of pain intensity.

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Twitter Usage Using Common Reference to Tinnitus

American Journal of Audiology ◽

10.1044/2020_aja-19-00055 ◽

2020 ◽

Vol 29 (2) ◽

pp. 206-217

Author(s):

Jianyuan Ni ◽

Monica L. Bellon-Harn ◽

Jiang Zhang ◽

Yueqing Li ◽

Vinaya Manchaiah

Keyword(s):

Nonprofit Organizations ◽

Temporal Trends ◽

Temporal Analysis ◽

Cross Sectional ◽

For Profit ◽

Common Reference ◽

Personal Experiences ◽

Twitter Users ◽

Sectional Analysis ◽

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Objective The objective of the study was to examine specific patterns of Twitter usage using common reference to tinnitus. Method The study used cross-sectional analysis of data generated from Twitter data. Twitter content, language, reach, users, accounts, temporal trends, and social networks were examined. Results Around 70,000 tweets were identified and analyzed from May to October 2018. Of the 100 most active Twitter accounts, organizations owned 52%, individuals owned 44%, and 4% of the accounts were unknown. Commercial/for-profit and nonprofit organizations were the most common organization account owners (i.e., 26% and 16%, respectively). Seven unique tweets were identified with a reach of over 400 Twitter users. The greatest reach exceeded 2,000 users. Temporal analysis identified retweet outliers (> 200 retweets per hour) that corresponded to a widely publicized event involving the response of a Twitter user to another user's joke. Content analysis indicated that Twitter is a platform that primarily functions to advocate, share personal experiences, or share information about management of tinnitus rather than to provide social support and build relationships. Conclusions Twitter accounts owned by organizations outnumbered individual accounts, and commercial/for-profit user accounts were the most frequently active organization account type. Analyses of social media use can be helpful in discovering issues of interest to the tinnitus community as well as determining which users and organizations are dominating social network conversations.

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