12.10 Regeneration and Repair of Nervous Tissue

Plasticity

the brain's ability to change, especially during childhood, by reorganizing after damage or by building new pathways based on experience

Regeneration

The ability to regrow a missing part of the body

Neurogenesis

the formation of new neurons

Epidermal growth factor

Abbreviated EGF; stimulates cells to reproduce and heal.

Chromatolysis

swelling of a neuron because of injury

Wallerian degeneration

degeneration of the distal portion of the axon and myelin sheath

Regeneration tube

formed by Schwann cells, basal lamina, and the neurilemma near the injury

Multiple sclerosis

myelin sheath destruction. disruptions in nerve impulse conduction

Epilepsy

chronic brain disorder characterized by recurrent seizure activity

Excitotoxicity

the property by which neurons die when overstimulated, as with large amounts of glutamate

Major depression

a disorder characterized by severe negative moods or a lack of interest in normally pleasurable activities

Dysthymia

a form of depression that is not severe enough to be diagnosed as major depression

Bipolar disorder

A mood disorder in which the person alternates between the hopelessness and lethargy of depression and the overexcited state of mania.

Seasonal affective disorder

Controversial disorder in which a person experiences depression during winter months and improved mood during spring. Can be treated using phototherapy, using bright light and high levels of negative ions.

Selective serotonin reuptake inhibitors

a group of second-generation antidepressant drugs that increase serotonin activity specifically, without affecting other neurotransmitters