The part of the nervous system contained in the skull; it includes the cerebrum, midbrain, cerebellum, pons, and medulla oblongata.
Mechanisms and neurochemicals in the brain (their signals, neurons, and connections) are studied through psychology (mind and behavior), neurogenetics (DNA and anatomy), neuroimaging (linking areas of the brain to function, like the hippocampus to memory or the amygdala to emotions), electrophysiology (neuron networks and electrical impulses), and neurotransmitters. The difference between the brain’s different signal systems is location—where the neurons are in the brain, what areas each connects with, and what neuron networks that control different brain functions they activate. Acetylcholine neurons in the base of the forebrain connect with the hippocampus and control memory. Dopamine neurons in the midbrain connect with the prefrontal cortex and govern drive and reward mechanisms. Serotonin neurons in the brainstem are linked to many cortical and other brain areas and control mood and emotion. The endogenous opioid (endorphin and encephalin) systems are distributed through the brain and spinal cord, neurons in the brainstem decreasing activity in ascending pathways for pain stimuli.
The mass of nerve tissue contained within the cranium, consisting of the cerebrum, cerebellum, pons, and medulla oblongata.
The part of the central nervous system situated inside the skull.
A mass of nervous tissue, the centre of sensation, thought, intelligence and emotion.
Mass of nervous tissue in the skull (cranium); the main part of the central nervous system, the primary center for regulating body activities. The brain includes the two hemi¬ spheres of the cerebrum, the cerebellum, the pons, and the medulla oblongata, each part with specialized functions. The brain is covered by protective membranes (meninges) and contains cavities (ventricles) containing cerebrospinal fluid.
The principal and most complex organ in the nervous system; the major control center for both basic body system maintenance and the highest levels of thought, emotion, and learning.
The enlarged and highly developed mass of nervous tissue that forms the upper end of the ‘central nervous system. The average adult human brain weighs about 1400 g (approximately 2% of total body weight) and is continuous below with the spinal cord. It is invested by three connective tissue membranes, the meninges, and floats in cerebrospinal fluid within the rigid casing formed by the bones of the skull. The brain is divided into the hindbrain (rhombencephalon), consisting of the medulla oblongata, pons Varolii, and ‘cerebellum; the midbrain (mesencephalon); and the forebrain (prosencephalon), subdivided into the cerebrum and the ‘diencephalon (including the thalamus and hypothalamus).
The brain and spinal cord together form the central nervous system (CNS). Twelve cranial nerves leave each side of the brain and 31 spinal nerves from each side of the cord: together these nerves form the peripheral nervous system. Complex chains of nerves lying within the chest and abdomen, and acting largely independently of the peripheral system, though linked with it, comprise the autonomic system and govern the activities of the viscera.
A large soft mass of nerve tissue contained within the cranium; the cranial portion of the central nervous system.
The main control center of the nervous system that is located inside the skull.
That part of the central nervous system that is contained within the cranium (skull).
A moist, spongy organ, located within the skull, that is made up of billions of neurons; it controls sense experiences, actions, thoughts, and memory.
Organ responsible for control of body activities and interpretation of information received from the senses.
Throughout Europe, one can find that calf, sheep, or pig brains are often available for purchase either as part of the head or separately. In the United States, however, these brains are typically sold as standalone items. These delectable morsels are widely considered a delicacy, with calf brains tending to be the most sought after. Despite the differences in sourcing, the same recipes can generally be employed when cooking with brains of any type.
The brain, situated within the cranium (skull), is the principal organ of the nervous system. It plays a vital role in receiving, organizing, and interpreting sensations transmitted by the nerves that extend from the central nervous system (consisting of the brain and spinal cord) to the rest of the body. Additionally, the brain initiates and coordinates the transmission of nerve signals involved in various activities such as speech, movement, thought, and emotion. Its intricate functions enable complex cognitive and physiological processes essential for human existence.
The adult brain typically weighs around 1.4 kilograms and is comprised of three primary structures: the brainstem, the cerebellum, and the largest component known as the cerebrum. The cerebrum consists of two hemispheres, the left and right, and is responsible for a wide range of cognitive functions. These structures collectively contribute to the intricate operations of the brain, enabling essential neurological processes and facilitating human capabilities.
Within each hemisphere of the cerebrum, there exists an outer layer referred to as the cortex. This cortex is composed of grey matter, which is abundant in nerve-cell bodies and serves as the primary region in the brain responsible for conscious thought, sensation, and movement. Beneath the cortex lie tracts of nerve fibers known as white matter, while deeper within the hemispheres, we find paired clusters of nerve cells called the basal ganglia. The surface of each hemisphere is marked by fissures (sulci) and folds (gyri), which divide it into distinct lobes, namely the occipital, frontal, parietal, and temporal lobes, named after the corresponding skull bones that overlay them. Connecting the two hemispheres is a thick band of nerve fibers called the corpus callosum. Together, these structures contribute to the complexity and functionality of the brain, enabling a wide array of cognitive processes and facilitating communication between different regions of the cerebrum.
The cerebrum encompasses a central collection of structures that include the thalami and the hypothalamus, which maintain close connections with the pituitary gland. Encircling the thalami is a complex network of nerve centers known as the limbic system. These interconnected structures serve as crucial links between different regions of the cerebrum and the brainstem, situated beneath the thalami. They play integral roles in regulating various physiological and cognitive processes, facilitating communication and coordination within the brain.
The brainstem primarily focuses on regulating essential functions vital to our survival, including breathing and blood pressure control. Located at the back of the brain, the cerebellum plays a crucial role in maintaining balance, posture, and coordinating muscle movements. Both the brainstem and the cerebellum operate predominantly at a subconscious level, autonomously managing these vital functions without conscious effort. Their intricate contributions are indispensable in sustaining our physiological well-being and motor coordination.
The brain and spinal cord are protected by three layers of membranes called meninges. These meninges encase and provide support to the central nervous system. Between these layers, as well as within the four main brain cavities called ventricles, circulates cerebrospinal fluid. This fluid serves vital functions by nourishing and cushioning the brain, acting as a protective buffer against potential impacts or trauma. The circulation of cerebrospinal fluid within the meninges and ventricles plays a crucial role in maintaining the overall health and well-being of the brain.
The brain possesses a rich and extensive blood supply. Blood is supplied to the brain through a circle of arteries that are nourished by the internal carotid arteries, which ascend along each side of the front of the neck before entering the base of the skull. Additionally, two vertebral arteries run parallel to the spinal cord, contributing to the brain’s blood flow. Remarkably, the brain receives approximately 20 percent of the blood pumped by the heart. This robust blood supply is essential for delivering oxygen, nutrients, and other vital substances necessary for the brain’s proper functioning and overall health.
The central organ of the nervous system, contained within the cranium. The brain is divided into three main parts—the cerebrum, the cerebellum, and the medulla oblongata. The largest part is the cerebrum, which controls the movements of the limbs, facial expression, sight, hearing, speech, and other functions. It is also the center of intelligence and responsible for the memory and emotions. Below the cerebrum is the cerebellum, which is responsible for the balance and the coordination of the limbs. The third, and smallest, portion is the medulla oblongata, containing the vital nerve centers controlling breathing and the heartbeat. The brain is protected by three membranes, the meninges. The principal and outermost of these is the dura mater, and the middle membrane is the arachnoid mater. These two membranes are practically in contact, but between them is a small quantity of liquid, the cerebrospinal fluid. The innermost membrane, the pia mater, is very delicate and closely applied to the brain. Cavities within the brain, the ventricles, contain a clear, colorless liquid, the cerebrospinal fluid, which also surrounds the spinal cord. This fluid is derived from the blood and undergoes changes in the presence of disease. The average weight of the adult brain is about 48 ounces in the male and 44 ounces in the female, though intelligence is not related to size. The average brain is said to contain some 15,000,000,000 cells.