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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 ?
Reduction in opioid- and cannabinoid-induced antinociception in rhesus monkeys after bilateral lesions of the amygdaloid complex.
Quaternary man now worked with his hammerstone around a core or nodule, removing small flakes to shape his tool into a circular disk-like form, an amygdaloid shape, or an elongated hache: "One has to remark", added then Reboux,
Amygdalar stimulation promotes glucocorticoid release, whereas large lesions of the amygdaloid complex reduce HPA axis activity (see Herman et al.
Leaf extract treatment during the growth spurt period has been shown to enhance hippocampal CA3 neuronal dendritic and amygdaloid neuronal dendritic arborization (regions concerned with learning and memory) in rats (Mohandas Rao et al.
Chronic stress induces contrasting patterns of dendritic remodeling in hippocampal and amygdaloid neurons.
12) Empirical brain studies have supported humanistic reflections on the importance of smell to memory and especially emotional memory; as ten Donkelaar explains in Clinical Neuroanatomy: Brain Circuitry and Its Disorders, the limbic lobe, in which the olfactory system is central, "contains all of the major cortical and amygdaloid structures known to be especially important for emotional and behavorial functions" and are involved in "memory processing and memory disorders" (14).
The lateral amygdaloid nucleus: Sensory interface of the amygdala in fear conditioning.
There is accumulated evidence that the amygdaloid complex of nuclei such as amygdale, representing the central emotional management within the human brain, gives emotional (affective) tone to the input sensory information even before its conscious processing (Simic and Goran 2009).
In neonatal rat pups, fresh leaf juice of the plant showed enhancement of amygdaloid neuronal dendritic arborization suggesting that it can be used for enhancing neuronal dendrites in stress and other neurodegenerative and memory disorders Mohandas Rao, et al.
It appears that one 'automatic', bottom-up, subcortical-amygdaloid pathway mediates non-consciously perceived fear, whereas consciously perceived fear is mediated by both subcorticalamygdaloid and cortical amygdaloid pathways.