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Lava rock containing amygdules. Also known as amygdaloidal lava.



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.

References in periodicals archive ?
Anatomical interactions between the central amygdaloid nucleus and the hypothalamic paraventricular nucleus of the rat: A dual tract-tracing analysis.
Corticosterone delivery to the amygdala increases corticotropin-releasing factor mRNA in the central amygdaloid nucleus and anxiety-like behavior.
Conversely, withdrawal-induced anxiety following chronic ethanol treatment was linked with increased HDAC activity levels and reduced histone acetylation in these amygdaloid brain regions (see figure 3).
The role of amygdaloid brain-derived neurotrophic factor, activity-regulated cytoskeleton-associated protein and dendritic spines in anxiety and alcoholism.
Central and medial amygdaloid brainderived neurotrophic factor signaling plays a critical role in alcohol-drinking and anxiety-like behaviors.
Interestingly, AChE was not inhibited in other ACh-rich areas, such as the anterior basolateral amygdaloid nucleus and lateral entorhinal cortex.
Posisynaptic mechanisms underlying responsiveness of amygdaloid neurons to nociceptin/orphanin FQ.
Amygdaloid pCREB and CBP levels both are significantly increased by acute ethanol exposure and decreased in rats undergoing withdrawal after chronic ethanol exposure (Pandey et al.
Finally, acute ethanol exposure increased CREB phosphorylation levels as well as the expression of BDNF and Arc in these amygdaloid structures of P, but not NP, rats (Moonat et al.
These data suggest that epigenetic modifications involving HDACs result in a refinement of amygdaloid chromatin structure, which may be a contributing factor that alters the expression of genes implicated in alcohol tolerance and dependence (figures 4 and 5).
Amygdaloid volume: Volume of the amygdala, an almond-shaped gray-matter mass located deep in each cerebral hemisphere, which may play an important role in the development of repeated AOD use and AOD dependence.
New perspectives in basal forebrain organization of special relevance for neuropsychiatric disorders: The striatopallidal, amygdaloid, and corticopetal components of substantia innominata.