The Human Brain

white matter

Whitish nervous tissue of the CNS consisting of neurons and their myelin sheaths.

cerebral hemispheres

two halves of the cerebral cortex, each of which serve distinct yet highly integrated functions. Right side is logic, left side is creative. The left side of the brain is responsible for controlling the right side of the body. It also performs tasks that have to do with logic, such as in science and mathematics. On the other hand, the right hemisphere coordinates the left side of the body, and performs tasks that have do with creativity and the arts.

Cerebellum

A large structure of the hindbrain that controls fine motor skills. The cerebellum receives information from the sensory systems, the spinal cord, and other parts of the brain and then regulates motor movements. The cerebellum coordinates voluntary movements such as posture, balance, coordination, and speech, resulting in smooth and balanced muscular activity.

Hypothalamus

A neural structure lying below the thalamus; it directs several maintenance activities (eating, drinking, body temperature), helps govern the endocrine system via the pituitary gland, and is linked to emotion and reward.

Frontal Lobe

A region of the cerebral cortex that has specialized areas for movement, abstract thinking, planning, memory, and judgement. It is, in essence, the "control panel" of our personality and our ability to communicate. Remember that damage here, Phineas Gage suffered an injury to this portion of his brain, (Autopsy and Lesion study)

Thalamus

A small structure above the brain stem that relays motor and sensory signals to the cerebral cortex. Heavily connected to the cerebral cortex and midbrain.

fMRI

A technique for revealing blood flow and, therefore, brain activity by comparing successive MRI scans. Functional magnetic resonance imaging or functional MRI measures brain activity by detecting changes associated with blood flow. This technique relies on the fact that cerebral blood flow and neuronal activation are coupled. When an area of the brain is in use, blood flow to that region also increases.

Pupil reflex

An automatic reflex of pupils contracting in response to bright light, controlled by the medulla oblongata and can indicate if a person is brain-dead or not, by testing to see if the medulla oblongata is still working.

Cerebrum

Area of the brain responsible for all voluntary activities of the body. is a large part of the brain containing the cerebral cortex (of the two cerebral hemispheres), as well as several subcortical structures, including the hippocampus, basal ganglia, and olfactory bulb.

Gray matter

Brain and spinal cord tissue that appears gray with the naked eye; consists mainly of neuronal cell bodies (nuclei) and lacks myelinated axons.

Broca's area

Controls language expression - an area of the frontal lobe, usually in the left hemisphere, that directs the muscle movements involved in speech.

Temporal Lobe

Located behind the ears extending around the brain. Involved in vision, memory, sensory input, language, emotion, and comprehension. Primarily focused on auditory perception. Contains the primary auditory cortex which processes sensory information from the ear and makes it into understandable units.

Somatosensory cortex

Located in the parietal lobe. Responsible for processing somatic sensations from receptors positioned throughout the body that are responsible for detecting touch, proprioception (i.e. the position of the body in space), nociception (i.e. pain), and temperature. Each of the four areas of the primary _____________ are arranged such that a particular location in that area receives information from a particular part of the body. This arrangement is referred to as somatotopic, and the full body is represented in this way in each of the four divisions of the _____________. Because some areas of the body (e.g. lips, hands) are more sensitive than others, they require more circuitry and cortex to be devoted to processing sensations from them. Thus, the somatotopic maps found are distorted such that the highly sensitive areas of the body take up a disproportionate amount of space in them

Occipital lobe

One of the four major lobes of the cerebral cortex in the brain of mammals. It is the visual processing center of the mammalian brain containing most of the anatomical region of the visual cortex. Are responsible for visual perception.

Parietal lobe

One of the four major lobes of the cerebral cortex in the brain of mammals. Main area for the sense of touch. Positioned at the back of the brain and is divided into two hemispheres. It functions in processing sensory information regarding the location of parts of the body as well as interpreting visual information and processing language and mathematics.

Peripheral nervous system (PNS)

One of two components that make up the nervous system of bilateral animals, with the other part being the central nervous system. Consists of the nerves and ganglia outside the brain and spinal cord

medulla oblongata

Part of the brainstem that controls vital life-sustaining functions such as heartbeat, breathing, blood pressure, and digestion. It is a cone-shaped neuronal mass responsible for autonomic (involuntary) functions ranging from vomiting to sneezing.

cerebral cortex

The intricate fabric of interconnected neural cells covering the cerebral hemispheres; the body's ultimate control and information-processing center. is the outer covering of gray matter over the hemispheres. It is also responsible for higher thought processes including speech and decision making . The cortex is divided into four different lobes, the frontal, parietal, temporal, and occipital, which are each responsible for processing different types of sensory information.

Brain

The mass of nerve tissue that is the main control center of the nervous system

Parasympathetic Nervous system

The other half of the autonomic nervous system. Responsible for regulating "rest-and-digest" or "feed and breed" activities that occur when the body is at rest, especially after eating, including sexual arousal, salivation, lacrimation (tears), urination, digestion and defecation. Its action is described as being complementary to that of the sympathetic nervous system, which is responsible for stimulating activities associated with the fight-or-flight response. Nerve fibers arise from the central nervous system.

Visual Cortex

The place where point-by-point information in the visual field is project along neurons. Part of the cerebral cortex that receives and processes sensory nerve impulses from the eyes.

Autonomic Nervous System

This system is regulated by the hypothalamus. This nervous system receives information via Efferent neurons from the CNA. A subdivision of the peripheral nervous system. Controls involuntary activity of visceral muscles and internal organs and glands. It is further broken up into the Sympathetic system and the parasympathetic system and the enteric system. Acts largely unconsciously and regulates bodily functions such as the heart rate, digestion, respiratory rate, pupillary response, urination, and sexual arousal.

Sympathetic (Nervous system)

This system prepares the body for intense physical activity and is often referred to as the fight-or-flight response. The parasympathetic nervous system has almost the exact opposite effect and relaxes the body and inhibits or slows many high energy functions

Spinal Cord

a long, thin, tubular structure made up of nervous tissue, that extends from the medulla oblongata in the brainstem to the lumbar region of the vertebral column. It is enclosed in the central canal containing cerebrospinal fluid. functions primarily in the transmission of nerve signals from the motor cortex to the body, and from the afferent fibers of the sensory neurons to the sensory cortex. It is also a center for coordinating many reflexes and contains reflex arcs that can independently control reflexes. It is also the location of groups of spinal interneurons that make up the neural circuits known as central pattern generators. These circuits are responsible for controlling motor instructions for rhythmic movements such as walking.

motor cortex

an area at the rear of the frontal lobes that controls voluntary movements is the region of the cerebral cortex involved in the planning, control, and execution of voluntary movements

Central Nervous System (CNS)

is the part of the nervous system consisting of the brain and spinal cord. The CNS is so named because it integrates the received information and coordinates and influences the activity of all parts of the bodies of bilaterally symmetric animals—that is, all multicellular animals except sponges and radially symmetric animals such as jellyfish—and it contains the majority of the nervous system. the spinal cord relays information up to the brain through spinal tracts through the "final common pathway"[8] to the thalamus and ultimately to the cortex.

Perception

organization, identification, and interpretation of sensory information in order to represent and understand the presented information, or the environment. This involves signals that go through the nervous system, which in turn result from physical or chemical stimulation of the sensory system. For example, vision involves light striking the retina of the eye, smell is mediated by odor molecules, and hearing involves pressure waves

Pituitary gland

synthesizes and secretes hormones. All releasing hormones (-RH) referred to, can also be referred to as releasing factors. pea-sized gland that sits in a protective bony enclosure called the sella turcica. It is composed of three lobes: anterior, intermediate, and posterior. In many animals, these three lobes are distinct.The intermediate is avascular and almost absent in human beings

Cranium

the portion of the skull that encloses the brain