Nociceptive Reflex in Patients With Schizophrenia: A Case-Control Study
Bibliographic record
Abstract
Background: Diminished pain sensitivity has been reported in patients in the acute phase of psychosis, as well as in stable patients. The cause of hypoalgesia in those patients is unknown. The aim of this study was to investigate the sensory thresholds, pain modalities, or other factors contributing to the perception or expression of physical pain in patients with schizophrenia (SCZ). Methods: This case-control study was conducted on 24 patients with SCZ and 12 healthy controls. Patients with SCZ were assessed by the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Positive and Negative Symptom Scale and Schizophrenia Cognition Rating Scale. All participants were subjected to full medical and neurological examination and nociceptive reflex. Results: There was no significant difference between cases and controls in nociceptive threshold, while it showed a significant difference at the subjective pain threshold as the case group needed a higher intensity of current to perceive as painful. There was a significant positive correlation between age, duration of SCZ and number of episodes and the nociceptive reflex. Also, there was a significant positive correlation between the negative symptoms of SCZ and cognitive impairment on one arm and the subjective pain threshold on the other arm. Conclusion: The pain insensitivity in patients with SCZ is not related to physiological changes in the nociceptive pathway, but rather may be related to change in the experience and expression of pain. Older age, longer duration of disease, more frequent episodes, negative symptoms, and cognitive impairment, but not antipsychotic medications, all are positively correlated with the increase in subjective pain threshold. J Neurol Res. 2021;11(1-2):20-26 doi: https://doi.org/10.14740/jnr656
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.002 |
| Meta-epidemiology (narrow) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.002 | 0.001 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.001 | 0.001 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.003 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".