Related Experiment Video
Updated: May 9, 2026
07:30
Brain Morphology of Cannabis Users With or Without Psychosis: A Pilot MRI Study
Published on: August 18, 2020
Cognitive impairments in poly-drug ketamine users
1Department of Psychiatry, Chinese University of Hong Kong, Hong Kong, China.
Addictive Behaviors
|August 1, 2013
Summary
Cognitive impairments in verbal and visual memory persist in former ketamine poly-drug users. This study highlights the lasting effects of ketamine and other substance abuse on cognitive function.
Area of Science:
- Neuroscience
- Psychiatry
- Addiction Medicine
Background:
- Cognitive impairment associated with substance abuse can be reversible.
- Ketamine users frequently engage in poly-substance abuse.
- This study investigates cognitive function in ketamine users and controls.
Purpose of the Study:
- To compare cognitive functions of current and former ketamine poly-drug users with non-users.
- To assess memory, executive function, and working memory.
- To evaluate depression and anxiety symptoms in users and controls.
Main Methods:
- 100 ketamine poly-drug users (current and ex-users) and 100 controls were recruited.
- Cognitive tests included memory, executive function, and intelligence assessments.
- Beck Depression Inventory and Hospital Anxiety Depression Scale measured psychological symptoms.
Main Results:
- Current users showed higher depression and anxiety than ex-users and controls.
- Both current and ex-users exhibited deficits in verbal and visual memory recall.
- No significant cognitive differences were observed between current and ex-ketamine users.
Conclusions:
- Ketamine poly-drug users experience persistent verbal and visual memory impairments.
- These memory deficits remain evident even after cessation of ketamine use.
- Further research is needed on the combined effects of ketamine and poly-drug use on memory.
Related Concept Videos
01:30Cognitive Enhancers: Cholinesterase Inhibitors and NMDA Receptor Antagonists
Cognitive enhancers, also known as "smart drugs," are substances used to enhance memory, mental alertness, and concentration. These can be natural or synthetic and improve cognition in conditions like Alzheimer's disease (AD) and other neurodegenerative diseases. Some common examples include caffeine, amphetamines, methylphenidate, modafinil, arecoline, donepezil, vortioxetine, and piracetam. These enhancers work on the principle of synaptic plasticity and altered circuit function. They...
01:29Hepatic Encephalopathy
DefinitionHepatic encephalopathy is a reversible neurologic syndrome that results from advanced liver dysfunction or portosystemic shunting. It leads to disturbances in cognition, behavior, and motor function due to the brain’s exposure to gut-derived toxins that the liver fails to detoxify.EtiologyThis condition develops either in the setting of acute fulminant hepatitis or progressively during chronic liver disease, such as cirrhosis and portal hypertension. Portosystemic shunting—including...
01:08Effect of Hepatic Disease on Pharmacokinetics: Dose Adjustments Due to Hepatic Impairment
Hepatic impairment, characterized by decreased liver function, does not uniformly mandate adjustments in drug dosage. Whether dosage modifications are necessary depends on various factors related to the drug's metabolism and elimination pathways. If a drug is primarily excreted via the kidneys and bypasses significant hepatic processing, if it undergoes minimal metabolic transformation in the liver, or if it is volatile and primarily expelled through the lungs, dose adjustments may not be...
01:28Depressants
Depressant drugs, including alcohol and sedative-hypnotics, diminish central nervous system activity by enhancing the action of gamma-aminobutyric acid (GABA), a neurotransmitter that reduces brain activity and promotes relaxation. These substances can have various therapeutic uses but also pose significant risks, especially when misused or combined.
Alcohol is a common depressant that can induce a sense of relaxation and reduced inhibition at low doses. Contrary to its occasional...
Alcohol is a common depressant that can induce a sense of relaxation and reduced inhibition at low doses. Contrary to its occasional...
01:23Nonlinear Pharmacokinetics: Dependence of Elimination Half-Life and Dose Clearance
The elimination half-life and drug clearance of drugs following nonlinear kinetics can vary with dosage. The Michaelis-Menten parameters and drug concentration influence these factors. As the dose increases, the elimination half-life tends to lengthen, resulting in a reduction in clearance and a disproportionately larger area under the curve. The total clearance can be derived from the Michaelis-Menten equation for drugs following a one-compartment model.
A study on guinea pigs examined the...
A study on guinea pigs examined the...
01:14CNS Depressants: Barbiturates and Benzodiazepines
CNS depressants include drugs from the category of barbiturates and benzodiazepines. They are valuable medications for managing anxiety disorders and insomnia. Barbiturates, once used to induce and maintain sleep, have been replaced mainly by benzodiazepines due to barbiturate's toxicity, tolerance, and overdose risks. They interact with GABAA receptors, leading to sedation at low doses and potentially coma and death at higher doses. Phenobarbital, a long-acting barbiturate, possesses...