Related Experiment Video
Updated: Jun 24, 2026
07:30
Brain Morphology of Cannabis Users With or Without Psychosis: A Pilot MRI Study
Published on: August 18, 2020
Cognitive impairment in encephalitis: P3 and MRI correlation
J Kalita1, U K Misra, A Srivastava
1Department of Neurology, Sanjay Gandhi PGIMS, Lucknow, India. jayanteek@yahoo.com
Electromyography and Clinical Neurophysiology
|March 14, 2009
Summary
Cognitive impairment is common in encephalitis, particularly Japanese encephalitis (JE) and herpes simplex encephalitis (HSE). Abnormal P3 event-related potentials correlate with cognitive deficits and MRI findings.
Area of Science:
- Neuroscience
- Infectious Diseases
- Clinical Neurophysiology
Background:
- Encephalitis, a serious brain inflammation, often leads to cognitive deficits.
- Limited research exists on P3 event-related potentials (P3 ERPs) in encephalitis patients.
- Understanding neurological sequelae is crucial for managing encephalitis outcomes.
Purpose of the Study:
- To investigate clinical, magnetic resonance imaging (MRI), and P3 changes in encephalitis patients.
- To correlate P3 abnormalities with cognitive function (Mini Mental State Examination - MMSE) and MRI findings.
- To assess the prevalence and types of cognitive impairment in different encephalitis etiologies.
Main Methods:
- Prospective evaluation of 30 encephalitis patients (Japanese encephalitis, herpes simplex encephalitis, nonspecific).
- Cognitive function assessed using MMSE one month post-illness.
- P3 ERPs recorded using an oddball auditory paradigm; MRI performed; diagnosis confirmed by ELISA/PCR.
Main Results:
- Cognitive impairment (abnormal MMSE) was frequent, especially in herpes simplex encephalitis (100%) and Japanese encephalitis (81%).
- Abnormal P3 ERPs were observed in 6 patients, with 5 showing concurrent cognitive deficits.
- MRI abnormalities were noted in 18 patients, frequently involving the thalamus; P3 abnormalities were more common with abnormal MMSE and MRI.
Conclusions:
- Cognitive impairment is a significant sequela of herpes simplex encephalitis and Japanese encephalitis.
- Abnormalities in P3 ERPs are associated with cognitive impairment and neuroimaging findings in encephalitis.
- P3 ERPs may serve as a valuable biomarker for detecting neurological damage and cognitive deficits post-encephalitis.
Related Concept Videos
01:19Encephalitis l: Introduction
Encephalitis is inflammation of the brain parenchyma, most often due to infections or autoimmune processes. It presents with neuropsychiatric features such as fever, altered mental status, behavioral changes, cognitive dysfunction, seizures, focal deficits, and sometimes autonomic instability. In some cases, the meninges are also involved, resulting in meningoencephalitis.Infectious CausesInfectious encephalitis is most commonly viral but can also result from bacterial, fungal, or parasitic...
01:26Encephalitis ll: Pathophysiology
Encephalitis is inflammation of the brain parenchyma caused by direct viral invasion or immune-mediated mechanisms triggered by infections or tumors. Both processes lead to neuronal injury, disrupted neurotransmission, and diverse neurological symptoms, often with overlapping clinical and pathological features.Autoimmune EncephalitisIn autoimmune encephalitis, antibodies target neuronal antigens on cell surfaces, synapses, or within neurons. A key example is anti-NMDAR encephalitis, which can...
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...
01:25Arboviral Encephalitis
Arboviral encephalitis refers to brain inflammation caused by arthropod-borne viruses, particularly those transmitted through mosquito vectors. Among these, West Nile virus (WNV), a member of the Flaviviridae family, is a significant public health concern. WNV is an enveloped, positive-sense, single-stranded RNA virus. Human infection typically begins when an infected mosquito introduces the virus into the dermis during feeding. The primary transmission cycle involves birds as amplifying hosts...