A benzodiazepine-site imaging signal is not a direct test of sedative response.
A PET study compared ten fragile X participants with ten controls using a flumazenil radiotracer. It reported reduced GABA-A benzodiazepine-site binding availability on average, with regional analyses including the thalamus.
The small selected sample and tracer methodology constrain inference. Binding potential depends on more than a simple receptor count and does not itself measure memory, sedation or clinical treatment benefit.
Describe the imaging endpoint before connecting it to pharmacology. A group difference cannot determine that an individual will require a higher dose or be protected from adverse effects. Those are separate exposure-response questions requiring patient-level evidence rather than extrapolation from a PET comparison.
Source: PMC4519313, supplied full-text paper. Findings are paraphrased; case-review implications are an interpretation.
Related: Forensic Toxicology: expert analysis and case review.