Thalamus Anatomy and Functions

A brain structure located in the diencephalon, acting as a relay center for sensory information and controlling selective attention. It can be thought of as the "gatekeeper" to the cortex.

A structure in the diencephalon that connects both hemispheres of the brain.

Specialized groups of nerve cells within the thalamus with distinct functions in processing and relaying information.

Thalamic nuclei that receive sensory information from the body and pass it on to the cortex.

Thalamic nuclei that connect different areas of the cortex, playing a role in higher cognitive functions.

Inputs to thalamic nuclei that carry specific information to be relayed to the cortex.

Inputs to thalamic nuclei that regulate and control the flow of information, influencing which information reaches the cortex.

The thalamus plays a key role in determining which sensory information reaches the cortex, filtering out irrelevant stimuli during sleep or in noisy environments.

Descending signals originating from the cortex that indicate which information should be processed and sent to the cortex, preventing overload and confusion.

The thalamus is responsible for transmitting all sensory modalities except smell to the primary sensory cortex.

The subjective experience of sensations, influenced by connections with the limbic system and prefrontal cortex. This process allows us to interpret sensations as pleasant or unpleasant, impacting our mood.

Nociceptive input is the signal from damaged tissues that travels to the thalamus. Only when this signal reaches the cortex is it consciously perceived as pain.

The brain's ability to integrate sensory input, planning, and execution of movements through connections with the basal ganglia, cerebellum, and motor cortex.

The thalamus plays a critical role in various aspects of memory, including factual-declarative and geographic memory, by relaying information from the hippocampus to the cortex.

The thalamus, through its connection with the brainstem's Ascending Reticular Activating System (ARAS), regulates cortical arousal and consciousness, allowing us to be alert and aware of our surroundings.

The thalamus serves as a processing center for auditory information. Sound waves are converted into electrical signals in the cochlea and relayed through the auditory pathway to the thalamus. The thalamus then sends this information to the auditory cortex for conscious perception.

The thalamus is a crucial relay center for visual information. Signals from the retina are transmitted to the thalamus, from where they are relayed to the visual cortex for processing.

The trigeminothalamic tract, originating from the trigeminal ganglion, carries sensory information from the face to the thalamus, specifically the VPM nucleus. This information is then relayed to the somatosensory cortex for processing.

The thalamus receives sensory information from the body, except for smell, and relays it to the primary somatosensory cortex.

The dorsal column-medial lemniscus pathway and spinothalamic tract carry sensory information from the dorsal root ganglia to the VPL of the thalamus.

The VPL, or ventral posterolateral nucleus, relays sensory information to all areas of the somatosensory cortex, except the primary.

The anterior thalamic nucleus receives input from the mammillary bodies in the hypothalamus and projects axons to the cingulate cortex, contributing to memory consolidation and selective attention.

The lateral dorsal thalamic nucleus receives input from the entorhinal cortex and projects axons to the cingulate cortex and parietal cortex, playing a role in motivation and selective attention.