The Rolandic area, also known as the central sulcus region, is a key part of the human brain. This area is important for both motor control and sensory processing. It is named after Luigi Rolando, a 19th-century Italian anatomist whose early work indicated this region was involved in generating movement.
Anatomical Location
The Rolandic area is defined by a prominent groove on the brain’s surface called the central sulcus. This sulcus runs approximately down the middle of each cerebral hemisphere, extending from the top of the brain downwards and forwards at an angle of about 70 degrees. It separates the frontal lobe from the parietal lobe.
The brain tissue directly in front of the central sulcus is the precentral gyrus, located within the frontal lobe. Immediately behind the central sulcus, in the parietal lobe, lies the postcentral gyrus. This arrangement means the central sulcus effectively divides the brain’s primary motor processing area from its primary sensory processing area.
Primary Functions
The precentral gyrus houses the primary motor cortex, which controls voluntary movements throughout the body. When you decide to move your arm or speak, signals originate here and activate the muscles required for that action. Different body parts are represented in specific locations along this gyrus; for instance, one area controls your hand, while another controls your foot.
Similarly, the postcentral gyrus contains the primary somatosensory cortex, which processes sensory information from the body. This includes sensations like touch, temperature, pain, and proprioception, the sense of your body’s position in space. When you feel the warmth of a cup or the texture of a fabric, these sensations are interpreted in this region.
The organization of these cortices follows somatotopy, often visualized as a “homunculus” or “little man.” This concept illustrates that different body parts are mapped onto specific areas of these gyri. Areas requiring fine motor control (like the hands and face) or having high sensory sensitivity (like the lips and fingertips) occupy disproportionately larger cortical regions. This detailed mapping allows for precise control of movement and accurate interpretation of sensory input.
Clinical Significance
Disruptions to the Rolandic area can lead to a range of neurological symptoms, depending on the affected part and nature of the damage. One notable condition is Rolandic epilepsy, also known as benign childhood epilepsy with centrotemporal spikes (BECTS). This is the most common childhood epilepsy syndrome, typically starting between ages 3 and 13, with a peak around 8 or 9.
Seizures in Rolandic epilepsy are often focal, beginning in a specific brain area, usually around the central sulcus. Common symptoms include unilateral facial sensorimotor symptoms, such as twitching or numbness on one side of the face, and oropharyngolaryngeal manifestations, which can involve difficulty speaking or excessive salivation. Seizures are often infrequent, with many children experiencing fewer than 10 in total, and frequently occur during sleep. The prognosis is excellent, as most children outgrow the condition by adolescence, typically by age 14 to 18.
Beyond epilepsy, damage to the Rolandic area from other causes, such as a stroke, brain tumor, or traumatic injury, can result in more persistent neurological deficits. If the primary motor cortex in the precentral gyrus is affected, individuals may experience motor weakness or paralysis on the opposite side of the body. Conversely, damage to the primary somatosensory cortex in the postcentral gyrus can lead to sensory disturbances, such as numbness, tingling sensations, or an impaired ability to feel touch or temperature.