Lemniscus (anatomy)

General Information
Latin	lemniscus
Greek
TA98
TA2
FMA
Details
System	Nervous system
Artery
Vein
Nerve
Lymphatic drainage
Precursor	Neural crest
Function	Sensory pathway
Identifiers
Clinical significance
Notes

The lemniscus is a bundle of secondary sensory fibers in the brainstem that is involved in the transmission of sensory information. The term "lemniscus" is derived from the Greek word for "ribbon" or "band," reflecting its appearance as a flat, ribbon-like tract.

Types of Lemnisci

There are several types of lemnisci in the central nervous system, each serving distinct functions:

• Medial lemniscus: This is a major sensory pathway that carries information about touch, vibration, and proprioception from the body to the thalamus. It originates in the dorsal column nuclei of the medulla oblongata and ascends through the brainstem.

• Lateral lemniscus: This tract is part of the auditory pathway and carries information from the cochlear nuclei to the inferior colliculus in the midbrain.

• Spinal lemniscus: Also known as the spinothalamic tract, it transmits information about pain and temperature from the body to the thalamus.

Function

The lemnisci are crucial for the processing and relay of sensory information to higher brain centers. They ensure that sensory inputs are accurately transmitted to the cerebral cortex for interpretation, allowing for the perception of various sensory modalities.

Clinical Significance

Damage to the lemnisci can result in sensory deficits. For example, lesions in the medial lemniscus can lead to loss of proprioception and fine touch, while damage to the lateral lemniscus can affect auditory processing.

See Also

• Nervous system
• Sensory system
• Brainstem
• Thalamus

References

Susan,

 Gray's Anatomy: The Anatomical Basis of Clinical Practice, 
 41st edition, 
 Elsevier, 
 2016, 
  
  
 ISBN 978-0-7020-5230-9,

Purves, Dale,

 Neuroscience, 
 Sinauer Associates, 
 2018, 
 Vol. 6th edition

External Links

• Lemniscus on WikiMD