Glossary D

Glossary D

Deductive validity refers to a property of some logical arguments such that it is impossible for the premises to be true and the conclusion(s) to be false. It also means logical soundness.

Deep sleep refers to 3rd and 4th stages of NREM sleep during which delta waves are produced.

A Deep Brain Stimulation (DBS) delivers a constant low electrical stimulation to a small region of the brain, through implanted electrodes connected to an implanted battery. It is used to partially restore normal movements in Parkinson's disease, essential tremor, and dystonia.

Deep dyslexia refers to a reading disorder characterized by an impaired ability to sound out words, while wholeword skills are unimpaired.

Deep lesioning is defined as the removal of tissue within the brain by use of an electrode.

Deep Processing refers to a a process that can help retrieve information from long-term memory

Deep sleep refers to the Stage 4 - slow-wave sleep; the deepest form of normal sleep.

Deep structure refers to an underlying syntactic structure that links various phrase structures through the application of various transformation rules; the level of linguistic structure assumed in transformational grammar that expresses the underlying semantic meaning of a sentence. In Chomsky's theory, Deep structure is the grammatical organization and meaning that underlies all language ; contrast with Surface structure.