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Lava rock containing amygdules. Also known as amygdaloidal lava.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.



an effusive rock with large, slightly elongated pores filled with secondary deposits of various minerals (quartz, zeolites, chlorites, and calcite). The term “amygdaloid” refers to the texture of the effusive rock regardless of its mineral composition. There are diabase, basaltic, porphyritic, and other types of amygdaloids. Amygdaloids are particularly common among ancient volcanic strata that have been subjected to hydrothermal alteration in the zeolitic facies of metamorphism.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.
References in periodicals archive ?
Yang et al., "Role of extra-cellular signal-regulated kinase in synaptic transmission and plasticity of a nociceptive input on capsular central amygdaloid neurons in normal and acid-induced muscle pain mice, "Journal of Neuroscience, vol.
Chattarji, "Recovery after chronic stress fails to reverse amygdaloid neuronal hypertrophy and enhanced anxiety-like behavior," Neuroscience, vol.
Martinez-Vargas et al., "Effect of electrical stimulation of the nucleus of the solitary tract on the development of electrical amygdaloid kindling in the cat," Epilepsia, vol.
Gloor et al., "Anatomic basis of amygdaloid and hippocampal volume measurement by magnetic resonance imaging," Neurology, vol.
Potential corticotropin-releasing factor pathways in the rat brain as determined by bilateral electrolytic lesions of the central amygdaloid nucleus and paraventricular nucleus of the hypothalamus.
* Recognizing (and labeling, naming, "tagging") the emotion (eg, sad, hurt, angry, embarrassed); this engages frontal lobe processes that diminishes amygdaloid limbic system overactivity (1)
Amaral DG, Price JL, Pitkanen A, Carmichael ST, 1992, Anatomical organization of the primate amygdaloid complex.
The MePD is important for higher-level, supramedullary control of cardiovascular functions (6-8), and, in this sense, sends projections to the central amygdaloid nucleus (CeA) and then to the A1 noradrenergic cells of the caudal ventrolateral medulla and the nucleus of the solitary tract (NTS; 9,10).
Effects of acute treatment and long-term treatment with MK-801 against amygdaloid kindled seizures in rats.
The magnitude of advantage for emotional as opposed to neutral stimuli does not alter with normal senescence (the moderate amygdaloid atrophy that occurs with normal senescence is not enough to interrupt the emotional-memory enhancement effect).
They are large osteoderms with an amygdaloid outline, one or more visceral keels and two well differentiated regions: a round end (the bulb), and a more elongated and irregularly ornamented region (the root).