rCBF changes associated with PPN stimulation in a patient with Parkinson's disease: A PET study
Bibliographic record
Abstract
Gait disturbances and akinesia are disabling symptoms in advanced Parkinson's disease (PD). The pedunculopontine nucleus (PPN) is involved in locomotion, control of posture, and behavioral states [i.e. wakefulness, rapid eye movement (REM) sleep]. Some reports have suggested that modulation of the activity of the PPN with deep brain stimulation (DBS) may be beneficial in the treatment of gait dysfunction and akinesia. To gain some insights on effects of PPN-DBS in the human brain, we used [(15)O] H(2)O positron emission tomography (PET) to measure changes in regional cerebral blood flow (rCBF) at rest during Off and On stimulation in an advanced PD patient with unilateral PPN-DBS. PPN-DBS increased rCBF in different subcortical areas most notably the thalamus, bilaterally. Double-blinded clinical evaluation revealed an improvement in motor function by approximately 20%. The PET changes provide for the first time evidence in the human brain that PPN-DBS may be able to influence and modify rCBF of closely connected subcortical structures. Given the importance of the PPN in locomotion, control of posture, and behavioral states, DBS may have significant implication for more complicated forms of movement disorders where deterioration of gait, postural instability, and REM sleep behavior disorders are very disabling.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
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 | 0.000 | 0.001 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.002 | 0.001 |
| Insufficient payload (model declined to judge) | 0.001 | 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".