thalamus

American  

[thal-uh-muhs] / ˈθæl ə məs /

noun

thalami plural

1. Anatomy. the middle part of the diencephalon through which sensory impulses pass to reach the cerebral cortex.

2. Botany. a receptacle or torus.

3. Also called thalamium.  an apartment for women in an ancient Greek house.

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thalamus British  

/ ˈθæləməs, θəˈlæmɪk /

noun

1. either of the two contiguous egg-shaped masses of grey matter at the base of the brain

2. both of these masses considered as a functional unit

3. the receptacle or torus of a flower

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thalamus Scientific  

/ thăl′ə-məs /

thalami plural

1. The part of the vertebrate brain that lies at the rear of the forebrain. It relays sensory information to the cerebral cortex and regulates the perception of touch, pain, and temperature.

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thalamus Cultural  

1. The part of the brain that coordinates nerve impulses relating to the senses of sight, hearing, touch, and taste.

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Other Word Forms

• postthalamic
  adjective
• subthalamic
  adjective
• thalamic
  adjective
• thalamically
  adverb
• transthalamic
  adjective

Etymology

Origin of thalamus

1695–1705; < New Latin; Latin: bedroom < Greek thálamos

Compare meaning

How does thalamus compare to similar and commonly confused words? Explore the most common comparisons:

• hypothalamus vs. thalamus

Explanation

The thalamus is an egg-shaped mass of gray matter that's located in the middle of the brain. The thalamus is responsible for transmitting sensory signals between different parts of the brain. The thalamus plays a crucial role in regulating consciousness, sleep, and alertness by directing sensory information to different parts of the brain. It receives input from sensory organs such as the eyes, ears, and skin and then relays that information to other regions of the brain for further processing. This important structure, which is located near the center of the brain, gets its name from the Greek word thalamos, which means "inner chamber."

Example Sentences

Professor Fumitaka Osakada, graduate student Masatoshi Nishimura, and their colleagues at the Graduate School of Pharmaceutical Sciences at Nagoya University developed assembloids that model interactions between the thalamus and the cortex.

From Science Daily • Jan. 7, 2026

Earlier research in rodents has shown that the thalamus plays an important role in organizing neural circuits in the cortex.

From Science Daily • Jan. 7, 2026

They found that neural activity spread from the thalamus into the cortex in wave like patterns, creating synchronized activity across cortical networks.

From Science Daily • Jan. 7, 2026

The team identified three transcriptional regulators essential for maintaining memories: Camta1 and Tcf4 in the thalamus, and Ash1l in the anterior cingulate cortex.

From Science Daily • Nov. 30, 2025

Ganglia geniculata are found for the first time in connexion with the optic tracts in the lower part of the thalamus.

From Encyclopaedia Britannica, 11th Edition, Volume 4, Slice 4 "Bradford, William" to "Brequigny, Louis" by Various