Bitumen battles – the phenomenon of road rage
Glossary
adrenaline and noradrenaline. Hormones, released by the adrenal glands, that are the first line of defence during any sudden stress. These hormones increase heart rate and blood pressure, and therefore increase blood flow to the muscles, allowing a 'flight or fight' response. These hormones are also called epinephrine and norepinephrine.
amygdala. An almond-shaped structure of the vertebrate brain, involved in the generation of emotions. It also plays a role in the development of memories.
autonomic nervous system. The part of our nervous system that regulates essential functions such as heartbeat and breathing, functions that occur without conscious involvement. It is sometimes called the involuntary nervous system. For more information see The autonomic nervous system (Neuroscience for Kids, University of Washington, USA) and Autonomic nervous system (National Dysautonomia Research Foundation, USA).
hormone. A substance produced in one part of the body and carried by the blood to another part of the body where it causes a response (eg, insulin, produced by the pancreas, that promotes the uptake of glucose by body cells). For more information see The hormones of the human (Kimball's Biology Pages, USA) and The hormones (Center for Bioenvironmental Research, Tulane and Xavier Universities, USA).
hypothalamus. A part of the brain that is connected to, and controls activity in, the pituitary gland. It also controls various aspects of homeostasis such as regulation of body temperature and appetite. There are regions of the hypothalamus that are associated with aggressive behaviour.
limbic system. Interconnecting parts of the brain that are associated with the control of emotions and memory. For more information see Limbic system (Universal Health Services Neurobehavioral Systems, USA) and The emotional nervous system – the limbic system (Shippensburg University, USA).
neurotransmitter. A chemical substance, given off by the terminals of a nerve cell or nerve fibre, which affects the next nerve cell or fibre in the chain, thus allowing a message to be passed between different links in the chain. It is the arrival of the electrical impulse at the end of the nerve fibre that causes the release of a neurotransmitter into the small gap (called the synapse) between nerve cells. The neurotransmitter travels across the synapse and excites or inhibits the next nerve cell in the chain.
peripheral nervous system. Consists of neurons connecting the central nervous system (the brain and the spinal cord) to the rest of the body. Sensory neurons bring information to the central nervous system from sensory receptors of the body. Motor neurons carry signals from the central nervous system to organs such as muscles and glands.
parasympathetic and sympathetic nervous systems. Divisions of the autonomic nervous system. When parasympathetic and sympathetic nerves innervate the same organ, they often have opposite effects. In general, the parasympathetic division acts to conserve energy (eg, stimulates digestion, slows the heart). The sympathetic division increases energy use and prepares the body for action (eg, accelerates the heart, increases metabolic rate).
serotonin. One of the neurotransmitters found in the brain. Studies have shown that low levels of serotonin are associated with increased levels of aggression in animals.
Page updated August 2006.