Related Experiment Video

Updated: Sep 27, 2026

Association Between Sleep Quality and Cognitive Symptoms in Patients with Major Depressive Disorder
04:33

Association Between Sleep Quality and Cognitive Symptoms in Patients with Major Depressive Disorder

Published on: April 26, 2024

Neurocognitive impairment in drug-free patients with major depressive disorder

Richard J Porter1, Peter Gallagher, Jill M Thompson

  • 1Department of Psychological Medicine, Christchurch School of Medicine, New Zealand.

The British Journal of Psychiatry : the Journal of Mental Science
|March 4, 2003
PubMed
Abstract

Insights

Medication-free patients with major depressive disorder (MDD) show significant neurocognitive impairments in attention and executive function. These deficits, particularly in learning and memory, may indicate brain dysfunction in depression.

Area of Science:

  • Neuroscience
  • Psychiatry
  • Cognitive Psychology

Background:

  • Major depressive disorder (MDD) is frequently associated with neurocognitive impairment.
  • The influence of psychotropic medications on cognitive function in MDD patients is a significant confounding factor.
  • Previous research has often failed to control for medication effects in studies of MDD and cognition.

Purpose of the Study:

  • To investigate neurocognitive function in patients diagnosed with MDD who are not taking psychotropic medication.
  • To compare the cognitive performance of medication-free MDD patients with that of healthy controls.
  • To determine if observed cognitive deficits in MDD are independent of medication effects.

Main Methods:

  • Forty-four out-patients meeting DSM-IV criteria for MDD were recruited.
  • All participating MDD patients were free of psychotropic medication for a minimum of six weeks.
  • A comprehensive neurocognitive battery was administered to both the MDD group and 44 demographically matched healthy controls.

Main Results:

  • Patients with MDD exhibited significant impairments in attention, executive function, visuospatial learning, and memory compared to healthy controls.
  • Motor and psychomotor functions were not significantly different between the groups.
  • The severity of depressive symptoms correlated with deficits in learning and memory, but not with executive function performance.

Conclusions:

  • This study demonstrates substantial neurocognitive impairment in young adult out-patients with MDD, independent of psychotropic medication.
  • The findings suggest that these cognitive deficits may serve as an objective indicator of underlying brain dysfunction in depression.
  • Further research is warranted to explore the neural mechanisms associated with these medication-unaffected cognitive impairments in MDD.

More Related Videos

Network Pharmacology and Validation of the Antidepressant Mechanisms of Qiangzhifang in a Chronic Restraint Stress-induced Depression Rat Model08:15

Network Pharmacology and Validation of the Antidepressant Mechanisms of Qiangzhifang in a Chronic Restraint Stress-induced Depression Rat Model

Published on: June 6, 2025

Development of a Virtual Reality Assessment of Everyday Living Skills10:32

Development of a Virtual Reality Assessment of Everyday Living Skills

Published on: April 23, 2014

Related Concept Videos

Effect of Hepatic Disease on Pharmacokinetics: Dose Adjustments Due to Hepatic Impairment01:08

Effect 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...
Cognitive Enhancers: Cholinesterase Inhibitors and NMDA Receptor Antagonists01:30

Cognitive 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...
Antidepressant Drugs: MAOIs and Other Agents01:23

Antidepressant Drugs: MAOIs and Other Agents

Atypical antidepressants, including bupropion (Wellbutrin), mirtazapine (Remeron), nefazodone (Serzone), trazodone (Desyrel), and vilazodone (Viibryd), offer unique mechanisms of action. Bupropion weakly inhibits dopamine and norepinephrine reuptake, aiding depression treatment and smoking cessation, with a low risk of sexual dysfunction. Mirtazapine enhances serotonin and norepinephrine neurotransmission, leading to sedation, increased appetite, and weight gain. As a result, it helps treat...
Drugs Affecting Neurotransmitter Release or Uptake01:21

Drugs Affecting Neurotransmitter Release or Uptake

Certain drugs can affect how neurotransmitters called catecholamines, are released or taken back up in the adrenergic neuron. They can have different effects on the body's sympathetic transmission. Reserpine, a natural compound found in the Rauwolfia shrub, blocks a transporter called vesicular monoamine transporter (VMAT), which leads to a buildup of catecholamines in the cell and reduces sympathetic transmission. Another drug called guanethidine works in multiple ways, including blocking...
Drugs Affecting Neurotransmitter Synthesis01:29

Drugs Affecting Neurotransmitter Synthesis

Drugs affecting neurotransmitter synthesis can impact the adrenergic neuron and the synthesis of neurotransmitters. For example, α-methyltyrosine and carbidopa target specific enzymes involved in catecholamine synthesis. α-methyltyrosine inhibits the enzyme tyrosine hydroxylase, which converts tyrosine into dopamine. By blocking this enzyme, α-methyltyrosine reduces dopamine production and other catecholamines. Carbidopa, on the other hand, inhibits the enzyme dopa decarboxylase, which converts...
Antidepressant Drugs: Overview01:25

Antidepressant Drugs: Overview

Antidepressant drugs are a class of medications primarily used for treating various mood disorders, including major depression, anxiety disorders, and other related conditions. These medicines work by modulating the neurotransmitter balance within the brain, alleviating depressive symptoms. Antidepressants can be broadly categorized into several groups according to their mechanism of action and chemical structure: Selective Serotonin Reuptake Inhibitors (SSRIs), Serotonin-Norepinephrine...