Glossary of words and terms to do with the brain

Blinded (clinical trials) or unblinded – blinding occurs on some clinical trials to help ensure that any effect seen is truly due to the treatment, ie. patients are not told which treatment they are receiving or when. Their doctor may also not know whether they are administering the trial treatment at the time. Unblinded or open trials are when everyone involved knows what is being administered. Learn more about clinical trials.

Blood-brain barrier – the mechanism by which the blood vessels of the brain prevent substances in the blood (such as bacteria) from reaching the brain. Obviously, this is good and vital mechanism, but it can work against a patient if anti-cancer drugs need to pass through the blood-brain barrier.

Brainstem – this connects the brain to the spinal cord, which runs down your neck and back. It controls the functions your body needs to stay alive, like breathing air, digesting food and circulating blood. Learn more about the brainstem.

Cerebellum – located below the cerebrum at the rear of the skull, the area that coordinates balance and muscle activity; part of the hindbrain. Learn more about the cerebellum.

Cerebrum – the largest area of the brain, this is the reasoning, thinking part and controller of intentional movement. Your memory also lives in the cerebrum. It is in two halves – the left and right cerebral hemispheres – which have slightly different functions: one side is used more for logical thinking and the other for creative thinking. Learn more about the cerebrum.

Cranium – the skull

Glia/glial – most of the brain tissue is composed of glial cells. Most brain tumours originate from glial cells.

Hindbrain – the lower or hind region of the adult brain comprising the cerebellum and much of the brain stem.

Infratentorial – the part of the brain just below the tentorium in the hindbrain (cerebellum) or brain stem.

Limbic system – the reactive part of your brain, where your personality lives. Learn more about the limbic system.

Lobes – each half of your brain, the right and left side, is called a cerebral hemisphere. Each of these is further divided into four lobes: frontal, parietal, temporal and occipital. Learn more about the lobes of the cerebrum.

Meninges – the three membranes that enclose the vertebrate brain and spinal cord: the pia mater, arachnoid, and dura mater. Learn more about the meninges.

Pituitary gland – the gland which produces hormones that circulate around in the blood. The pituitary hormones regulate the amount of all other hormones that are secreted elsewhere in your body. Learn more about the pituitary gland.

Randomisation – people taking part in a clinical trial are put into different treatment groups at random. Each group gets a different treatment; for instance, one group will get the new drug and the other will get the standard treatment they would get if they were not in the trial (the control group). Patients in control groups may get a dummy treatment called a placebo.

Skull base – the bones at the bottom of the skull

Supratentorial – the part of the brain just above the tentorium or anywhere apart from the hindbrain (cerebellum) or brain stem.

Tentorium – a flap of tissue that is part of the meninges. It separates the hindbrain and the brain stem from the rest of the brain. You may hear the words supratentorial or infratentorial.