A | B | C | D | E | F | G | H | I | K | L | M | N | O | P | R | S | T | V | W
A
| Term | Definition |
|---|---|
| Acetylcholine |
A neurotransmitter in both the brain, where it may help regulate memory, and in the peripheral nervous system, where it controls the actions of skeletal and smooth muscle. |
| Action Potential |
This occurs when a neuron is activated and temporarily reverses the electrical state of its interior membrane from negative to positive. This electrical charge travels along the axon to the neuron’s terminal where it triggers or inhibits the release of a neurotransmitter and then disappears. |
| Adrenal Cortex |
An endocrine organ that secretes corticosteroids for metabolic functions: aldosterone for sodium retention in the kidneys, androgens for male sexual development, and estrogens for female sexual development. |
| Adrenal Medulla |
An endocrine organ that secretes epinephrine and norepinephrine for the activation of the sympathetic nervous system |
| Affective Psychosis |
A psychiatric disease relating to mood states. It is generally characterized by depression unrelated to events in the life of the patient, which alternates with periods of normal mood or with periods of excessive, inappropriate euphoria and mania. |
| Agonist |
A neurotransmitter, a drug or other molecule that stimulates receptors to produce a desired reaction |
| Amino Acid Transmitters |
The most prevalent neurotransmitters in the brain, these include glutamate and aspartate, which have excitatory actions, and glycine and gamma-amino butyric acid (GABA) which have inhibitory actions |
| Amnesia |
“Inability to remember events or experiences. Memory loss. includes: 1) Anterograde amnesia: inability to retain the memory of events occurring after the time of the injury or disease which brought about the amnesic state. 2) Retrograde amnesia: inability to recall the memory of events which occurred prior to the time of the injury or disease which brought about the amnesic state.” [ref] |
| Amygdala |
1. An almond-shaped structure in the forebrain that is an important component of the limbic system; involved in producing and responding to nonverbal signs of anger, avoidance, defensiveness, and fear. 2. A small mass of gray matter that inspires aversive cues, such as the freeze reaction, sweaty palms, and the tense-mouth display. 3.A primeval arousal center, originating in early fishes, which is central to the expression of negative emotions in man. |
| Androgens |
Sex steroid hormones, including testosterone, found in higher levels in males than females. They are responsible for male sexual maturation. |
| Anosognosia |
Impaired awareness or denial of one’s disorder. A significant problem in several kinds of strokes and in neuropsychiatric disorders such as schizophrenia and bipolar disorder. It is strikingly manifest when a person with a paralysed limb claims it is still functioning. [One of Professor Ramachandran’s patients, who had suffered a stroke which had paralysed the left side of her body, refused to accept that her arm couldn’t move. Even though lucid in every other aspect (including awareness of the fact that she had suffered a stroke) she claimed her left arm was carrying out tasks even though clearly it wasn’t. An explanation may involve close analysis of the different roles of the left and right hemispheres of the brain.] |
| Antagonist |
A drug or other molecule that blocks receptors. Antagonists inhibit the effects of agonists |
| Aphasia |
Disturbance in language comprehension or production, often as a result of a stroke |
| Auditory Nerve |
A bundle of nerve fibers extending from the cochlea of the ear to the brain, which contains two branches: the cochlear nerve that transmits sound information and the vestibular nerve that relays information related to balance |
| Autonomic Nervous System |
A part of the peripheral nervous system responsible for regulating the activity of internal organs. It includes the sympathetic and parasympathetic nervous systems |
| Axon |
The fiber-like extension of a neuron by which the cell sends information to target cells |
B
C
| Term | Definition |
|---|---|
| Capgras’ delusion |
A rare syndrome in which the patient is convinced that close relatives usually parents, spouse, children or siblings are impostors. It may be caused by damage to the connections between the areas of the brain dealing with face recognition and emotional response. A sufferer might recognise the faces of his loved ones but not feel the emotional reaction normally associated with the experience |
| Catecholamines |
The neurotransmitters dopamine, epinephrine and norepinephrine that are active both in the brain and the peripheral sympathetic nervous system. These three molecules have certain structural similarities and are part of a larger class of neurotransmitters known as monoamines |
| Cerebral Cortex |
The outermost layer of the cerebral hemispheres of the brain. It is responsible for all forms of conscious experience, including perception, emotion, thought and planning |
| Cerebral Hemispheres |
The two specialized halves of the brain. The left hemisphere is specialized for speech, writing, language and calculation; the right hemisphere is specialized for spatial abilities, face recognition in vision and some aspects of music perception and production |
| Cerebrospinal Fluid |
A liquid found within the ventricles of the brain and the central canal of the spinal cord |
| Cholecystokinin |
A hormone released from the lining of the stomach during the early stages of digestion which acts as a powerful suppressant of normal eating. It also is found in the brain |
| Circadian Rhythm |
A cycle of behavior or physiological change lasting approximately 24 hours |
| Classical Conditioning |
Learning in which a stimulus that naturally produces a specific response (unconditioned stimulus) is repeatedly paired with a neutral stimulus (conditioned stimulus). As a result, the conditioned stimulus can become able to evoke a response similar to that of the unconditioned stimulus |
| Cochlea |
A snail-shaped, fluid-filled organ of the inner ear responsible for transducing motion into neurotransmission to produce an auditory sensation |
| Cognition |
The process or processes by which an organism gains knowledge of or becomes aware of events or objects in its environment and uses that knowledge for comprehension and problem-solving. |
| Cone |
A primary receptor cell for vision located in the retina. It is sensitive to color and used primarily for daytime vision |
| Confabulate |
to fabricate a narrative or experience; to “invent memories which are then taken as true” by the inventor; to form “false memories, perceptions, or beliefs about the self or the environment as a result of neurological or psychological dysfunction.[ref]” including a deficiency of viatmine B1 (thiamine) as a result of alcoholism [ref]. Associated with specific brain disfunctions (Korsakoff’s Syndrome, neuroal trauma-induced anosognosia…); recently covered in The Confabulating Mind: How the Brain Creates Reality By Armin Schnider,Oxford University Press: 2008 |
| Conservative |
when referring to the an organism’s traits, more ancient in an evolutionary sense. Traits are presumed to be maintained in descendents because of their service in meeting fundamental needs. In this sense, the more ancient a trait, the more fundamental the need it serves; this does not preclude the “retasking” of a trait to meet more “recent” needs |
| Cornea |
A thin, curved transparent membrane on the surface of the front of the eye. It begins the focusing process for vision |
| Corpus Callosum |
The large bundle of nerve fibers linking the left and right cerebral hemispheres |
| Cortisol |
A hormone manufactured by the adrenal cortex. In humans, it is secreted in greatest quantities before dawn, readying the body for the activities of the coming day |
| Cotard’s syndrome |
A disorder in which a patient asserts that he is dead, claiming to smell rotting flesh or worms crawling over his skin. It may be an exaggerated form of Capgras’ delusion, in which not just one sensory area (ie face recognition) but all of them are cut off from the limbic system. This would lead to a complete lack of emotional contact with the world |
D
E
F
G
H
| Term | Definition |
|---|---|
| Hippocampus |
A seahorse-shaped structure located within the brain and considered an important part of the limbic system. It functions in learning, memory and emotion |
| Hormones |
Chemical messengers secreted by endocrine glands to regulate the activity of target cells. They play a role in sexual development, calcium and bone metabolism, growth and many other activities |
| Hypothalamus |
1. A subcortical group of nuclei in the forebrain which serves a. the limbic system, b. the autonomic nervous system, and c. the endocrine system. 2. A thumbnail-sized neuro structure which organizes basic nonverbal responses, such as aggression, anger, sexuality, and fear. [Nonverbal Dictionary] The many nuclei have various functions which include regulating the activities of internal organs, monitoring information from the autonomic nervous system and controlling specific endocrine functions of the pituitary gland. |
I
K
L
M
N
O
| Term | Definition |
|---|---|
| Organelles |
Small structures within a cell that maintain the cells and do the cells’ work |
P
R
| Term | Definition |
|---|---|
| Reafference |
The component of sensory input an animal receives as a consequence of its own movements. (Thus, in the case of movement of the limbs, reafference is the proprioceptive or visual sensation that arises as a direct consequence of the motor act. (“process of relaying messages from limbic system via entorhinal cortex to sensory cortices, in parallel with limbic commands to motor systems, serving (1) to compensate in advance for changes in sensory input accompanying actions, and (2) to sustain states of expectancy and attention.” — from Freeman, Societies of Brains) (Is this related to Reafference and the origin of the self in early nervous system evolution–Jékely et al. 2021) |
| Receptor Cell |
Specialized sensory cells designed to pick up and transmit sensory information |
| Receptor Molecule |
A specific molecule on the surface or inside of a cell with a characteristic chemical and physical structure. Many neurotransmitters and hormones exert their effects by binding to receptors on cells |
| Reticular System |
area in brainstem that regulates arousal and activity in higher brain areas. Signals from various sources are filtered. Much information goes to (or through) the thalamus to influence the cerebral cortex. Medial nuclei are the elements of the “ascending reticular system” |
| Reuptake |
A process by which released neurotransmitters are absorbed for subsequent re-use |
| Rod |
A sensory neuron located in the periphery of the retina. It is sensitive to light of low intensity and specialized for nighttime vision |
S
T
V
W
| Term | Definition |
|---|---|
| Wernicke’s Area |
A brain region responsible for the comprehension of language and the production of meaningful speech |