The brain is the most miraculous and multifaceted of all body parts;the most intriguing and mystifying part of the human body. It performs innumerable functions simultaneously within a split second and is the most studied organ. Here are some remarkable brain facts not known by many people with a fully functional brain: The human brain, weighs only about 3lbs.
Neuroscience of sex differences The adult human brain weighs on average about 1. Each hemisphere is divided into four main lobes although Terminologia Anatomica and Terminologia Neuroanatomica also include a limbic lobe and treat the insular cortex as a lobe.
The brainstem includes the midbrain, the ponsand the medulla oblongata. Behind the brainstem is the cerebellum Latin: The membranes are the tough dura mater ; the middle arachnoid mater and the more delicate inner pia mater.
Between the arachnoid mater and the pia mater is the subarachnoid spacewhich contains the cerebrospinal fluid. Dashed areas shown are commonly left hemisphere dominant Main articles: Cerebrum and Cerebral cortex Major gyri and sulci on the lateral surface of the cortex Lobes of the brain The cerebrum is the largest part of the human brain, and is divided into nearly symmetrical left and right hemispheres by a deep groove, the longitudinal fissure.
It is 2 to 4 millimetres 0. The largest part of the cerebral cortex is the neocortexwhich has six neuronal layers. The rest of the cortex is of allocortexwhich has three or four layers. The hemispheres are connected by five commissures that span the longitudinal fissurethe largest of these is the corpus callosum.
There are many small variations in the secondary and tertiary folds. These areas are distinctly different when seen under a microscope.
The primary sensory areas receive signals from the sensory nerves and tracts by way of relay nuclei in the thalamus. Primary sensory areas include the visual cortex of the occipital lobethe auditory cortex in parts of the temporal lobe and insular cortexand the somatosensory cortex in the parietal lobe.
The remaining parts of the cortex, are called the association areas. These areas receive input from the sensory areas and lower parts of the brain and are involved in the complex cognitive processes of perceptionthoughtand decision-making.
The temporal lobe controls auditory and visual memorieslanguageand some hearing and speech. Below the corpus callosum is the septum pelluciduma membrane that separates the lateral ventricles. Beneath the lateral ventricles is the thalamus and to the front and below this is the hypothalamus. The hypothalamus leads on to the pituitary gland.
At the back of the thalamus is the brainstem.
Below and in front of the striatum are a number of basal forebrain structures. These include the nucleus accumbensnucleus basalisdiagonal band of Brocasubstantia innominataand the medial septal nucleus.
These structures are important in producing the neurotransmitteracetylcholinewhich is then distributed widely throughout the brain. The basal forebrain, in particular the nucleus basalis, is considered to be the major cholinergic output of the central nervous system to the striatum and neocortex.
Cerebellum Human brain viewed from below, showing cerebellum and brainstem The cerebellum is divided into an anterior lobea posterior lobeand the flocculonodular lobe.
Brainstem The brainstem lies beneath the cerebrum and consists of the midbrainpons and medulla. It lies in the back part of the skullresting on the part of the base known as the clivusand ends at the foramen magnuma large opening in the occipital bone.
The brainstem continues below this as the spinal cord protected by the vertebral column. Ten of the twelve pairs of cranial nerves [a] emerge directly from the brainstem.
Types of neuron include interneuronspyramidal cells including Betz cellsmotor neurons upper and lower motor neuronsand cerebellar Purkinje cells. Betz cells are the largest cells by size of cell body in the nervous system.
Astrocytes are the largest of the glial cells. They are stellate cells with many processes radiating from their cell bodies. Some of these processes end as perivascular end-feet on capillary walls. Myelin basic proteinand the transcription factor, OLIG2 are expressed in oligodendrocytes.List of human anatomical features.
Jump to navigation Jump to search. This article does not cite any List of regions in the human brain; Surface anatomy. Facts about the human brain.
The human brain is the largest brain of all vertebrates relative to body size. It weighs about lbs. ( kilograms). The healthy human brain contains tens of billions of neurons—specialized cells that process and transmit information via electrical and chemical signals.
They send messages between different parts of the brain, and from the brain to the muscles and organs of the body. Alzheimer’s disease.
The Human Brain The human body is divided into many different parts called organs. All of the parts are controlled by an organ called the brain, which is located in the head. The brain weighs about pounds, and has a whitish-pink appearance. The brain is made up of many cells, and is th.
The brain is one of the largest and most complex organs in the human body. It is made up of more than billion nerves that communicate in trillions of connections called synapses. The brain is.  In this text I will be mainly interested in the implementation of the human cognition system in the human brain.
I will try to give a model which will be both realistic (using neurons as building blocks and does not contain magical features), and interesting (explains the major features of the human cognition).