delirium A state of altered attention, arousal, and thought, often caused by an acute medical condition.

delusion A false belief, not generally endorsed by the individual's culture, held despite contradictory evidence.

epilepsy A chronic disorder consisting of intermittent episodes of excessive neuronal electrical discharge (seizures).

ictal Relating to a seizure.

partial seizure An episode of excessive electrical discharge originating from a discrete region of cerebral cortex and remaining confined to one part of the cortex.

psychosis A condition in which unreal beliefs or experiences are believed to represent reality.

Hallucinations are involuntary sensory experiences perceived as emanating from the external environment, in the absence of stimulation of relevant sensory receptors. They were first defined in this manner in 1837 by Esquirol, who differentiated them from illusions, which are perceptual misinterpretations of existing external stimuli. Hallucinations can occur in a variety of contexts but are perhaps most striking and debilitating in the setting of schizophrenia, in which they are combined with a failure to realize that they do not represent reality. In this instance, they are generally experienced as real, emotionally significant, and related to concurrent delusions, and they represent a form of psychosis. Hallucinations can occur in any sensory modality or can involve multiple modalities, with auditory hallucinations most common in schizophrenia and other illnesses traditionally termed psychiatric and visual hallucinations most common in illnesses termed neurologic. This article presents a functional neuroanatomic approach to hallucinations, describing and analyzing them in terms of disorders of sensory input, midbrain/thalamus, and higher brain regions, including cortical sensory, limbic, and frontal regions. It also discusses other investigational approaches to hallucinations as well as treatment considerations. The focus is on visual and auditory hallucinations because they occur most frequently and have been most thoroughly investigated.

Anxiety and Depression 101

Anxiety and Depression 101

Everything you ever wanted to know about. We have been discussing depression and anxiety and how different information that is out on the market only seems to target one particular cure for these two common conditions that seem to walk hand in hand.

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