On the base of the frontal lobe it overlies the anterior perforated substance through which the striate arteries enter the interior of the brain. On the temporal lobe the olfactory cortex covers the rostral portion of the parahippocampal gyrus including a medial bulge known as the uncus or uncinate gyrus. From the olfactory cortex, olfactory information is relayed via the mediodorsal nucleus of the thalamus to the insular and orbitofrontal cortex. The insular cortex, which is buried in the depths of the Sylvian fissure, also
| 1.1. Quadratus labii superior: Is a broad sheet, the origin of which extends from the side of the nose to the zygomatic bone. Its medial fibers form the angular head, which arises by a pointed extremity from the upper part of the frontal process of the maxilla and passing obliquely downward and lateralward divides into two slips. One of these is inserted into the greater alar cartilage and skin of the nose; the other is prolonged into the lateral part of the upper lip, blending with the infraorbital head and with the Orbicularis oris. The intermediate portion or infraorbital head arises from the lower margin of the orbit immediately above the infraorbital foramen, some of its fibers being attached to the maxilla, others to the zygomatic bone.
It has widespread connections with the rest of the forebrain and the midbrain. Partly through nerves and partly through hypothalamic hormones, the hypothalamus conveys messages to the pituitary gland, altering its release of hormones (Kalat, 2003). According to “American Accreditation Health Commission,” The hypothalamus is responsible for certain metabolic processes and other activities of the autonomic nervous system. It synthesizes and secretes certain neurohormones, often called hypothalamic-releasing hormones, and these in turn stimulate or inhibit the secretion of pituitary hormones. The hypothalamus controls body temperature, hunger, thirst, fatigue, sleep, and circadian cycle.
The main sulcus is the central sulcus, which indents the superior-medial surface of each hemisphere. This sulcus runs downward and forward on the lateral aspect, and is the only sulcus to indent the superior-medial boarder, as well be separated from the lateral sulcus below. The deep cleft on the inferior lateral surface is the lateral sulcus, and is used as a marker to separate the lobes of the hemispheres. The lateral sulcus has a stem which arises on the interior surface, and is further subdivided into three rami: the anterior horizontal ramus most anterior, the anterior ascending ramus, and
In the classic nomenclature(28) the vermis and hemisphere of the cerebellum is divided into three lobes namely anterior, posterior and flocculonodular lobe (Fig 2 and 3), by two deep fissures known as the primary fissure between the anterior and posterior lobes and the posterolateral fissure between the tonsil and flocculonodular lobe(24,25). The anterior lobe is bound anteriorly by superior medullary velum and posteriorly by the primary fissure. The vermis and hemispheres in the anterior lobe are further divided into lobules by two fissures namely precentral fissure and the preculminate fissure. The vermis is divided into three lobules namely lingula, central lobule and culmen. Lingula and the central lobule separated by the precentral fissure, central lobule and the culmen separated by the preculminate sulcus.
The frontal lobe’s main functions are movement control and language production that thrive from the primary motor cortex. Whereas Wernicke’s area is located on the left side of the temporal lobe, called superior temporal gyrus, that is link with the auditory cortex, which associates memories, comprehension of language, emotion, and sensory input. There is a difference in aphasia between Broca’s and Wernicke’s area. Once the Broca’s area is damaged the person would have
These muscles are named for the orientation of their fibers, the Superior and Inferior Longitudinalis both run the length of the tongue in the transverse plane, across the coronal plane, and along the sagittal plane. The Superior Longitudinalis runs along the full length of the top and back of the tongue along the medial line, this muscle draws the tip of the tongue to the posterior. The Inferior Longitudinalis inserts posterior to the tip of the tongue and originates more laterally, aiding in retraction and depression. The Transversus originates on the media fascia and inserts on the lateral edges of the full length of the tongue with the fibers running across the sagittal plane and parallel to both the coronal and transverse planes. The Transversus draws the sides of the tongue medially.
How do the physical properties of the ears help the brain decode and interpret sounds? Sound travels as osccialtion through some medium. The function of ears is to transmit the sound into electric messages which are sent to the brain which perceives and interprets the sound. Ears consist of three parts the outer ear, middle and inner ears. The outer ear consists of the pinna which collects the sound and transmits it to the ear canal, which amplifies the sound and transmits it to the tympanic membrane, the division between the outer ear and the middle ear.
White matter is a component of the central nervous system, in the brain and superficial spinal cord, and consists mostly of glial cells and myelinated axons that transmit signals from one region of the cerebrum to another and between the cerebrum and lower brain centers. Gray matter is a major component of the central nervous system, consisting of neuronal cell bodies, neuropil (dendrites and myelinated as well as unmyelinated axons), glial cells (astroglia and oligodendrocytes) and capillaries. Grey matter is
The nervous system is defined by the presence of a special type of cell, called the neuron. Neurons send signals with rapid precision to other cells with special structures that allow them to accomplish this task. Sensory neurons carry impulses or electrochemical signals to the interneurons of the brain. The interneurons interpret these impulses while the motor neurons carry