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: ["Chemical"].

Please return the output as a JSON object of the format: {"Chemical": ["Arsenic", ...]}. 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:

Facilitative effect of serotonin(1A) receptor agonists on cognition in patients with schizophrenia. Disturbances of cognitive function are considered to largely affect the outcome in patients with schizophrenia. There is much attention to the role of psychotropic compounds acting on serotonin (5-HT) receptors in ameliorating cognitive deficits of the disease. Among the 5-HT receptor subtypes, the 5-HT(1A) receptor is attracting particular interests as a potential target for enhancing cognition, based on preclinical and clinical evidence. The neural network underlying the ability of 5-HT(1A) agonists to treat cognitive impairments of schizophrenia likely includes dopamine, glutamate, and gamma-aminobutyric acid neurons. Recent advances of electrophysiological measures, such as event-related potentials, have provided insights into facilitative effects on cognition of some atypical antipsychotic drugs or related compounds acting directly or indirectly on 5-HT(1A) receptors. These considerations are expected to promote the development of novel therapeutics for the betterment of functional outcome in people suffering from schizophrenia.
{"Chemical": ["5-HT", "gamma-aminobutyric acid", "serotonin", "glutamate", "dopamine"]}