cerebral cortex

Examples of cerebral cortex in the following topics:

• The Brain

  • The cerebral cortex is essentially a sheet of neural tissue folded in a way that allows a large surface area to fit within the confines of the skull.
  • The left and right hemispheres of the cerebral cortex are nearly symmetrical.
  • Its functions includes relaying sensory and motor signals to the cerebral cortex and regulating consciousness, sleep, and alertness.
  • It likely acts as a relay between a variety of subcortical areas and the cerebral cortex.
  • Distinguish between the cerebellum, cerebral cortex, and brain stem regions of the brain

• Motor Areas

  • The motor areas of the brain are located in both hemispheres of the cortex.
  • Premotor cortex: Located anterior to the primary motor cortex and responsible for some aspects of motor control.
  • Buried deep in the white matter of the cerebral cortex are interconnected subcortical masses of cerebral gray matter called basal nuclei (or basal ganglia) that are involved in motor control.
  • The basal nuclei receive input from the substantia nigra of the midbrain and motor areas of the cerebral cortex and send signals back to both of these locations.
  • $$Topography of the human motor cortex, including the premotor cortex, SMA, primary motor cortex, primary somatosensory cortex, and posterior parietal cortex.

• Parts of the Cerebellum

  • The cerebellum has the appearance of a separate structure attached to the bottom of the brain, tucked underneath the cerebral hemispheres.
  • The surface of the cerebellum is covered with finely spaced parallel grooves, in striking contrast to the broad irregular convolutions of the cerebral cortex.
  • Like the cerebral cortex, the cerebellum is divided into two hemispheres.
  • It sends fibers to deep cerebellar nuclei that in turn project to both the cerebral cortex and the brain stem, thus providing modulation of descending motor systems.
  • It receives input exclusively from the cerebral cortex (especially the parietal lobe) via the pontine nuclei (forming corticopontocerebellar pathways), and sends output mainly to the ventrolateral thalamus (in turn connected to motor areas of the premotor cortex and primary motor area of the cerebral cortex) and to the red nucleus.

• Thalamus

  • The thalamus (derived from the Greek meaning "inner chamber") is a midline symmetrical structure within the brain, situated between the cerebral cortex and midbrain.
  • Its functions include relaying sensory and motor signals to the cerebral cortex and regulating consciousness, sleep, and alertness.
  • It is generally believed to act as a relay between a variety of subcortical areas and the cerebral cortex.
  • Each of the primary sensory relay areas receives strong back projections from the cerebral cortex.
  • Thalamic nuclei have strong reciprocal connections with the cerebral cortex, forming thalamo-cortico-thalamic circuits that are believed to be involved with consciousness.

• Overview of the Cerebrum

  • The cerebrum contains the cerebral cortex (of the two cerebral hemispheres), as well as several subcortical structures, including the hippocampus, basal ganglia, and olfactory bulb.
  • In larger mammals, the cerebral cortex is folded into many gyri and sulci, which allows it to expand in surface area without taking up much greater volume.
  • Each hemisphere of the mammalian cerebral cortex can be broken down into four functionally and spatially defined lobes: frontal, parietal, temporal, and occipital.
  • Speech and language are mainly attributed to parts of the cerebral cortex.
  • The cerebral cortex is the outer layer depicted in dark violet.

• Neural Mechanisms (Cortex)

  • Similarly to how involuntary respiration's lower functions are controlled by the lower brain, voluntary respiration's higher functions are controlled by the upper brain, namely parts of the cerebral cortex.
  • The primary motor cortex is the neural center for voluntary respiratory control.
  • Different parts of the cerebral cortex control different forms of voluntary respiration.
  • Topography of the primary motor cortex, on an outline drawing of the human brain.
  • Each part of the primary motor cortex controls a different part of the body.

• Cephalic Phase

  • Neurogenic signals that initiate the cephalic phase of gastric secretion originate from the cerebral cortex, and in the appetite centers of the amygdala and hypothalamus.
  • The cerebral cortex sends messages to hypothalamus, the medulla, and the parasympathetic nervous system via the vagus nerve, and to the stomach (gastric glands in walls of fundus and body of stomach).

• Aging and the Nervous System

  • One of the effects of aging on the nervous system is the loss of neurons in the cerebral cortex.
  • Differential characteristics are pointed out in the hippocampus, cerebral cortex, and ventricles.

• Cerebral Lobes

  • The frontal lobe contains most of the dopamine-sensitive neurons in the cerebral cortex.
  • The two occipital lobes are the smallest of the four paired lobes in the human cerebral cortex.
  • The temporal lobe is a region of the cerebral cortex located beneath the lateral fissure on both cerebral hemispheres of the mammalian brain.
  • The superior temporal gyrus includes an area where auditory signals from the ear first reach the cerebral cortex and are processed by the primary auditory cortex in the left temporal lobe.
  • Distinguish between the frontal, temporal, parietal, and occipital lobes of the cerebral cortex

• Sensory Areas

  • The cerebral cortex is connected to various subcortical structures such as the thalamus and the basal ganglia.
  • Most sensory information is routed to the cerebral cortex via the thalamus.
  • The primary somatosensory cortex, located across the central sulcus and behind the primary motor cortex, is configured to generally correspond with the arrangement of nearby motor cells related to specific body parts.
  • For example, the right primary somatosensory cortex receives information from the left limbs, and the right visual cortex receives information from the left eye.
  • Similarly, there is a tonotopic map in the primary auditory cortex and a somatotopic map in the primary sensory cortex.