You will be shown an abstract from a biomedical research paper. Given this abstract, your task is to extract all unique entities of the following types: ["Disease", "Chemical"].

Please return the output as a JSON object of the format: {"Chemical" : ["Naloxone", ...], "Disease" : ["Hypotensive", ...]}. The keys should be entity types and values should be lists of extracted entities belonging to the corresponding type. If you cannot find entities belonging to a specific type, the value should be [].

Only output the JSON object and do not include any additional text.

Abstract:

Increased mental slowing associated with the APOE epsilon4 allele after trihexyphenidyl oral anticholinergic challenge in healthy elderly. OBJECTIVES: The objectives of this study were to examine the relationship between APOE epsilon4 and subjective effects of trihexyphenidyl on measures reflecting sedation and confusion and to investigate the relationship between trihexyphenidyl-induced subjective effects and objective memory performance. METHODS: This study comprised 24 cognitively intact, health elderly adults (12 APOE epsilon4 carriers) at an outpatient geriatric psychiatry research clinic. This was a randomized, double blind, placebo-controlled, three-way, crossover experimental design. All participants received 1.0 mg or 2.0 mg trihexyphenidyl or placebo administered in counterbalanced sequences over a period of three consecutive weeks. Bond and Lader's visual analog scales and alternate versions of the Buschke Selective Reminding Test were administered in a repeated measures design at baseline, 1, 2.5, and 5 hours postdrug administration. RESULTS: A 2.0-mg oral dose of trihexyphenidyl resulted in increased subjective ratings of mental slowness in carriers of the APOE epsilon4 allele only. Drug effects as determined by difference scores between 2.0 mg trihexyphenidyl and placebo on ratings of mental slowness significantly correlated with total and delayed recall on the Buschke Selective Reminding Test in carriers of the APOE epsilon4 allele only. However, no significant effects were found with other visual analog scales reflecting subjective sedation and clear-headedness. CONCLUSION: The epsilon4 allele in healthy elderly was associated with increased subjective mental slowing after trihexyphenidyl anticholinergic challenge.
{"Chemical": ["trihexyphenidyl"], "Disease": ["mental slowness", "confusion", "mental slowing"]}