Regions · Grey Matter

Every region in Grey Matter, filterable by its attributes.

- Amygdala: The amygdala is an almond-sized group of nuclei deep in each temporal lobe, in front of the hippocampus, that decides quickly whether something matters emotionally, above all whether it is a threat, and starts the body's response before deliberate thought has caught up. - Basal ganglia: The basal ganglia are a set of deep nuclei that decide which of the actions the cortex proposes is allowed to start, and that learn from reward which actions to repeat until they become habits. - Brain: The brain (the encephalon) is everything of the central nervous system that sits inside the skull: the cerebrum with its two hemispheres, the cerebellum behind and below it, and the brainstem that continues into the spinal cord. - Brainstem: The brainstem is the stalk that joins the cerebrum to the spinal cord and keeps the body alive without thought: it drives breathing, sets heart rate and blood pressure, runs swallowing, coughing and vomiting, and keeps the cortex awake. - Cerebellum: The cerebellum is the folded structure at the back of the brain, below the occipital lobes and behind the brainstem, that makes movements smooth and accurate by predicting what each command will do and correcting it before the error shows. - Cerebral cortex: The cerebral cortex is the folded sheet of grey matter, two to four millimetres thick, that covers both hemispheres and does the brain's perceiving, acting, remembering and deliberating. - Cingulate cortex: The cingulate cortex is the band of cortex that wraps around the corpus callosum on the inner face of each hemisphere, connecting what the brain feels and wants with what it attends to and does. - Frontal lobe: The frontal lobe is the front third of each hemisphere, the part of the cortex that turns goals into behaviour: it holds the plan, chooses among options, keeps impulses in check and finally sends the commands that move the body. - Hippocampus: The hippocampus is a curved strip of cortex on the inner face of each temporal lobe that turns experiences into lasting memories: it binds the sights, sounds, places and feelings of an episode together so that the episode can be recalled later, and it builds the map that lets an animal know where it is. - Hypothalamus: The hypothalamus is a small region at the base of the brain, about the size of an almond, that keeps the body's internal conditions in balance: it measures temperature, water, salt, energy and time of day, and corrects them through behaviour, the autonomic nervous system and hormones. - Insula: The insula is a lobe of cortex hidden inside the lateral fissure that tells the brain how the body feels from the inside: it receives taste and the signals of the heart, lungs, gut, temperature and pain, and turns them into felt states such as hunger, nausea, disgust or a racing heart. - Limbic system: The limbic system is a traditional name for the set of structures on the inner edge of each hemisphere that join emotion, motivation and memory to the body's responses: what is felt, what is wanted and what is remembered because it mattered. - Locus coeruleus: The locus coeruleus is a small nucleus in the pons of the brainstem that supplies almost all the noradrenaline of the cortex, hippocampus, thalamus and cerebellum, and through it a few tens of thousands of neurons set the arousal of the whole brain. - Motor cortex: The motor cortex is the strip of the frontal lobe just in front of the central sulcus that turns a decided action into commands for muscles, each hemisphere moving the opposite side of the body. - Parietal lobe: The parietal lobe is the upper back part of each hemisphere that builds the brain's model of where things are: where the body is, where objects are around it, where attention should go and, by extension, how large a quantity is. - Pituitary gland: The pituitary gland is a pea-sized gland hanging below the hypothalamus that carries the brain's orders to the rest of the endocrine system: on instruction from the hypothalamus it releases the hormones that set the activity of the thyroid, the adrenal glands and the gonads, and those that regulate growth, milk and wat - Prefrontal cortex: The prefrontal cortex is the front of the frontal lobe, the region that keeps a goal in mind and bends perception, memory and action toward it: it plans, holds information for the next few seconds, weighs options against their consequences and stops actions that do not serve the goal. - Primary auditory cortex: The primary auditory cortex (A1) is the patch of the upper temporal lobe where sound first reaches the cortex, organised by pitch so that low and high frequencies land at opposite ends of a map. - Primary somatosensory cortex: The primary somatosensory cortex (S1) is the strip of the parietal lobe just behind the central sulcus where touch arrives in the cortex: pressure, vibration, temperature, pain and the position of the limbs from the opposite half of the body each reach their own spot on a map of the body. - Spinal cord: The spinal cord is the cable of nervous tissue in the vertebral canal that carries sensation up and commands down between the brain and the body, and that runs simple reflexes by itself. - Temporal lobe: The temporal lobe is the lower side of each hemisphere, below the lateral (Sylvian) fissure, that turns sounds and shapes into things recognised: it hears, it knows what a word or an object means, it recognises faces, and on its inner face it forms new memories. - Thalamus: The thalamus is a pair of egg-shaped masses of grey matter at the centre of the brain through which almost everything that reaches the cortex passes: it relays the senses, the motor loops of the cerebellum and basal ganglia, and the signals that set the level of wakefulness. - Visual cortex: The visual cortex is the part of the occipital lobe, at the back of the brain, that receives the signals from the eyes (relayed through the thalamus) and builds them into what is seen.