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Psychopathological effects of solitary confinement.

Psychopathological reactions to solitary confinement were extensively described by nineteenth-century German clinicians. In the United States there have been several legal challenges to the use of solitary confinement, based on allegations that it may have serious psychiatric consequences. The recent medical literature on this subject has been scarce. The author describes psychiatric symptoms that appeared in 14 inmates exposed to periods of increased social isolation and sensory restriction in solitary confinement and asserts that these symptoms form a major, clinically distinguishable psychiatric syndrome.

Adult↗

A withdrawal syndrome after abrupt discontinuation of alprazolam.

A patient who received therapeutic doses of alprazolam for 8 weeks experienced a withdrawal syndrome beginning 18 hours after its abrupt discontinuation. Short-acting and minimally sedating benzodiazepines may have increased potential for withdrawal reactions.

Adult↗

Hypnotic alteration of somatosensory perception.

Effects of hypnotic alterations of perception on amplitude of somatosensory event-related potentials were studied in 10 highly hypnotizable subjects and 10 subjects with low hypnotizability. The highly hypnotizable individuals showed significant decreases in amplitude of the P100 and P300 waveform components during a hypnotic hallucination that blocked perception of the stimulus. When hypnosis was used to intensify attention to the stimulus, there was an increase in P100 amplitude. These findings are consistent with observations that highly hypnotizable individuals can reduce or eliminate pain by using purely cognitive methods such as hypnosis. Together with data from the visual system, these results suggest a neurophysiological basis for hypnotic sensory alteration.

Attention↗

Psychosis as a state of aberrant salience: a framework linking biology, phenomenology, and pharmacology in schizophrenia.

OBJECTIVE: The clinical hallmark of schizophrenia is psychosis. The objective of this overview is to link the neurobiology (brain), the phenomenological experience (mind), and pharmacological aspects of psychosis-in-schizophrenia into a unitary framework. METHOD: Current ideas regarding the neurobiology and phenomenology of psychosis and schizophrenia, the role of dopamine, and the mechanism of action of antipsychotic medication were integrated to develop this framework. RESULTS: A central role of dopamine is to mediate the "salience" of environmental events and internal representations. It is proposed that a dysregulated, hyperdopaminergic state, at a "brain" level of description and analysis, leads to an aberrant assignment of salience to the elements of one's experience, at a "mind" level. Delusions are a cognitive effort by the patient to make sense of these aberrantly salient experiences, whereas hallucinations reflect a direct experience of the aberrant salience of internal representations. Antipsychotics "dampen the salience" of these abnormal experiences and by doing so permit the resolution of symptoms. The antipsychotics do not erase the symptoms but provide the platform for a process of psychological resolution. However, if antipsychotic treatment is stopped, the dysregulated neurochemistry returns, the dormant ideas and experiences become reinvested with aberrant salience, and a relapse occurs. CONCLUSIONS: The article provides a heuristic framework for linking the psychological and biological in psychosis. Predictions of this hypothesis, particularly regarding the possibility of synergy between psychological and pharmacological therapies, are presented. The author describes how the hypothesis is complementary to other ideas about psychosis and also discusses its limitations.

Antipsychotic Agents↗

Selective pharmacological activation of limbic structures in human volunteers: a positron emission tomography study.

Using a pharmacological probe, procaine hydrochloride, the authors elicited consistent and selective activation of anterior limbic and paralimbic structures in normal human volunteers as documented by H215O positron emission tomography. This activation was associated with a range of emotional, somatic, and visceral experiences, often similar to those experienced during the aura of temporal lobe epilepsy. Several subjects also experienced panic attacks. This study confirms that selective anterior limbic/paralimbic activity in normal human volunteers evokes many emotional phenomena as well as common "ill-defined" symptoms observed in clinical conditions. The present combination of procaine challenge and neuroimaging provides a noninvasive procedure to probe the contribution of different anterior limbic and paralimbic structures to normal human emotions and to neuropsychiatric disorders.

Adult↗

Perceptual aberration and schizotypy: a cautionary note.

This study assessed 51 college students for associations between Continuous Performance Test performance and schizotypy scale scores. Results suggest that perceptual aberration scores, while generally correlated with overall schizotypy scores, may not be adequate as a single-criterion measure of schizotypy.

Adult↗

Analyzing the traumatic impact of childhood visual impairment.

Material is presented from three analyses involving the impact on adult functioning of childhood trauma to the visual system. The clinical process by which unrecognized but ongoing traumatic reactions are identified for subsequent analysis is described. It is of particular importance, with these patients, to recognize their lifelong experience of visual confusion resulting from problems in their visual anatomy. Only then can fantasies and affects related to these physically induced states of confusion be worked through. Working through these reactions promotes the neutralization of related primitive narcissistic affects, mourning, and realistic accommodation, and leads to a more intact and integrated sense of self, and a marked increase in self-esteem. With this newly integrated sense of self, the complex interaction between physically induced confusion states and more typical developmental conflicts with objects can be worked through, resulting in more realistic and intense cathexes of the external world. The trauma suffered by these patients had been greatly compounded by its having gone unrecognized. To miss this yet again in an analysis is to repeat the past and retraumatize the patient. These findings have clear implications for patients with other biologically related symptoms (e.g., ADD, ADHD, and dyslexia).

Adult↗

Effect of visual impairment on driving.

The aim of the study was to determine the effect on driving of restricting vision. This was undertaken by comparing the driving performance of young, normal subjects under conditions of simulated visual impairment with a baseline condition. Visual impairment was simulated using goggles designed to replicate the effects of cataracts, binocular visual field restriction, and monocular vision. All subjects had binocular visual acuity greater than 6/12 when wearing the goggles and thus satisfied the visual requirements for a driver's license. Driving performance was assessed on a closed-road circuit for a series of driving tasks including peripheral awareness, maneuvering, reversing, reaction time, speed estimation, road position, and time to complete the course. Simulated cataract resulted in the greatest detriment to driving performance, followed by binocular visual field restriction. The monocular condition did not significantly affect driving performance for any of the driving tasks assessed.

Adult↗