Difference Between Primary and Secondary Somatosensory Cortex

Difference Between Primary and Secondary Somatosensory Cortex: The primary somatosensory cortex and the secondary somatosensory cortex have distinct roles. The primary somatosensory cortex primarily handles the reception and processing of sensory information from the somatic senses proprioceptive senses and certain visceral senses. In contrast, the secondary somatosensory cortex is responsible for storing and processing spatial and tactile memory associated with sensory experiences.

The Somatic sensations arise when sensory receptors detect stimuli primarily located in the skin muscles joints and tendons. The somatosensory cortex, comprising different regions plays a crucial role in receiving and processing sensory information from the somatic sensory system. Among these regions, the primary somatosensory cortex receives peripheral sensory information directly while the secondary somatosensory cortex functions to store and further process these inputs.

Difference Between Primary and Secondary Somatosensory Cortex

Feature	Primary Somatosensory Cortex	Secondary Somatosensory Cortex
Location	Postcentral gyrus of the parietal lobe	the Adjacent to the primary somatosensory cortex in the parietal lobe
Function	Processes of basic sensory information	Processes with more complex aspects of somatosensation integrate sensory inputs
Sensory Inputs	Touch, proprioception, temperature	Texture, shape, temperature, pain, higher-order somatosensory qualities
Somatotopic Organization	Present, with specific areas for the different body parts	Present which integrates information from multiple body parts
Cognitive Functions	Limited involvement in cognitive processes	Higher-order cognitive functions related to somatosensation
Interaction	Sends processed information to the other brain regions	Receives inputs from the primary somatosensory cortex and other brain regions
Role in Pain Perception	Processes sensory aspects of pain	the Processes emotional and cognitive aspects of pain
Examples	Localizing touch on the skin senses body position	Recognizing objects by touch integrating sensory information with emotions and memories

What is Primary Somatosensory Cortex?

The primary somatosensory cortex also known as S1 is located on the postcentral gyrus of the parietal lobe in the brain. It plays a crucial role in receiving and processing sensory information from somatic, proprioceptive, and visceral senses. This area composed of the Brodmann areas 1, 2, 3a, and 3breceives inputs related to the touch, pain, body position, and other somatic sensations.

Among the subdivisions within the primary somatosensory cortex area 3 receives the majority of the somatosensory inputs. Area 3b is primarily responsible for the processing of touch sensations. At the same time, area 3a processes information from the proprioceptors which provide feedback on the position and movement of the body parts. Area 3b relays touch information to areas 1 and 2 for further processing. Area 1 is particularly involved in perceiving the texture of objects while Area 2 is responsible for perceiving size shape and proprioception.

What is Secondary Somatosensory Cortex?

The secondary somatosensory cortex also known as S2 is the integral component of the somatosensory system. It is positioned within the parietal operculum region situated above the primary somatosensory cortex and posterior to it. Much like the primary somatosensory cortex S2 plays a vital role in the processing of somatosensory information. It exhibits responsiveness to both somatosensory and visual stimuli. S2 is believed to be involved in higher-order functions such as sensorimotor integration of the information from both halves of the body, attention learning, and memory.

In terms of structure, S2 comprises two specific regions namely Brodmann areas 40 and 43. However, our understanding of the structural organization and functional aspects of the human secondary somatosensory cortex remains limited when compared to the primary somatosensory cortex.

FAQs on Primary and Secondary Somatosensory Cortex

Q1: What is the primary and secondary somatosensory cortex?

Answer:

The primary and secondary somatosensory cortices are regions of the brain that process sensory information related to touch temperature, pain, and body position. They are part of the somatosensory system which allows us to perceive and interpret sensations from our body and the surrounding environment.

Q2: Where are the primary and secondary somatosensory cortex located?

Answer:

The primary somatosensory cortex, also known as S1 is located in the postcentral gyrus of the parietal lobe which is situated towards the top and back of the brain. The secondary somatosensory cortex also called S2 is located just behind the primary somatosensory cortex.

Q3: What is the function of the primary somatosensory cortex?

Answer:

The primary somatosensory cortex is the primarily responsible for processing and interpreting basic sensory information from the body. It receives input from the sensory receptors throughout the body and organizes the information in a topographic manner known as the somatotopic map. Different regions of the primary somatosensory cortex correspond to the specific body parts allowing for the precise localization and discrimination of the sensory stimuli.

Q4: What is the function of the secondary somatosensory cortex?

Answer:

The secondary somatosensory cortex is involved in the more complex processing of the somatosensory information. It integrates information from the primary somatosensory cortex and other brain areas to form a more comprehensive perception of touch, texture, and spatial relationships. It is also involved in processing the emotional and cognitive aspects of the somatosensory experiences.

Q5: How does the primary and secondary somatosensory cortex interact?

Answer:

The primary somatosensory cortex processes initial sensory input and sends information to the secondary somatosensory cortex. The secondary somatosensory cortex, in turn, integrates and refines the sensory information allowing for a more nuanced perception and understanding of the tactile stimuli. The interaction between these two areas enables a complex and multi-dimensional experience of the touch and other somatosensory sensations.