Bipolar Research Today is a free monthly online journal that collates and summarizes the latest research about Bipolar, including details on bipolar disorder, symptoms, treatment, depression, medication.

Perceptual switch rates with ambiguous structure-from-motion figures in bipolar disorder.

Krug K, Brunskill E, Scarna A, Goodwin GM, Parker AJ

Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford OX1 3PT, UK.

Slowing of the rate at which a rivalrous percept switches from one configuration to another has been suggested as a potential trait marker for bipolar disorder. We measured perceptual alternations for a bistable, rotating, structure-from-motion cylinder in bipolar and control participants. In a control task, binocular depth rendered the direction of cylinder rotation unambiguous to monitor participants' performance and attention during the experimental task. A particular direction of rotation was perceptually stable, on average, for 33.5s in participants without psychiatric diagnosis. Euthymic, bipolar participants showed a slightly slower rate of switching between the two percepts (percept duration 42.3s). Under a parametric analysis of the best-fitting model for individual participants, this difference was statistically significant. However, the variability within groups was high, so this difference in average switch rates was not big enough to serve as a trait marker for bipolar disorder. We also found that low-level visual capacities, such as stereo threshold, influence perceptual switch rates. We suggest that there is no single brain location responsible for perceptual switching in all different ambiguous figures and that perceptual switching is generated by the actions of local cortical circuitry.

Published 8 May 2008 in Proc Biol Sci.
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Articles on Bipolar published 8 May 2008:

Response to lithium of a cell surface ECTO-NOX protein with time-keeping characteristics.   Neurosci Lett.

Lithium has been used widely both as a clinical agent to treat manic depressive disorders and as a substance targeted to the regulation of the circadian cycle. In this study, we show that lithium at physiological concentrations of less than 1muM uniquely induces an ECTO-NOX activity previously inactive from plant (soybean), murine (3T3 cells) and human (HUVEC and HeLa cells) sources and resets the period of the constitutive CNOX. The average period length of the new oscillation set induced by ... [Abstract] [Full-text]

Articles on Bipolar published 7 May 2008:

Psychotic mania associated with mefloquine in a bipolar patient.   South Med J, 101(5): 550-1.

A 63-year-old male patient with a history of bipolar I disorder presented to the emergency department in an acutely psychotic state. The patient had just returned from vacation in a malarial high-risk area and, as a result, had taken five weekly doses of mefloquine for prophylaxis. The patient's bipolar disorder was being treated with lithium, and he had been stable for about 8 years. All organic causes of psychosis were ruled out. The patient was admitted to the inpatient psychiatric unit and ... [Abstract] [Full-text]

Chronic Administration of Valproic Acid Reduces Brain NMDA Signaling via Arachidonic Acid in Unanesthetized Rats.   Neurochem Res.

Evidence that brain glutamatergic activity is pathologically elevated in bipolar disorder suggests that mood stabilizers are therapeutic in the disease in part by downregulating glutamatergic activity. Such activity can involve the second messenger, arachidonic acid (AA, 20:4n - 6). We tested this hypothesis with regard to valproic acid (VPA), when stimulating glutamatergic N-methyl-D: -aspartate (NMDA) receptors in rat brain and measuring AA and related responses. An acute subconvulsant dose ... [Abstract] [Full-text]

Articles on Bipolar published 6 May 2008:

A mutation in mouse Disc1 that models a schizophrenia risk allele leads to specific alterations in neuronal architecture and cognition.   Proc Natl Acad Sci U S A.

DISC1 is a strong candidate susceptibility gene for schizophrenia, bipolar disorder, and depression. Using a mouse strain carrying an endogenous Disc1 orthologue engineered to model the putative effects of the disease-associated chromosomal translocation we demonstrate that impaired Disc1 function results in region-specific morphological alterations, including alterations in the organization of newly born and mature neurons of the dentate gyrus. Field recordings at CA3/CA1 synapses revealed a ... [Abstract] [Full-text]

Antecedents and sequelae of sudden parental death in offspring and surviving caregivers.   Arch Pediatr Adolesc Med, 162(5): 403-10.

OBJECTIVES: To examine the psychiatric antecedents that put parents at risk for early death, and the psychological sequelae of bereavement in offspring and caregivers. DESIGN: A population-based study. SETTING: Bereaved families were recruited through the coroner's records and by advertisement. Control families were recruited by random-digit dialing and advertisement. PARTICIPANTS: Families with biological offspring from 7 to 25 years of age in which 1 parent died of suicide, accident, or ... [Abstract] [Full-text]

Articles on Bipolar published 5 May 2008:

The PDLIM5 gene and lithium prophylaxis: An association and gene expression analysis in Sardinian patients with bipolar disorder.   Pharmacol Res.

A number of studies support the notion that lithium interacts with the protein kinase C (PKC) pathway, an important mediator of several intracellular responses to neurotransmitter signaling. PDLIM5 (PDZ and LIM domain 5; LIM) is an adaptor protein that selectively binds the isozyme PKC(varepsilon) to N-type Ca(2+) channels in neurons. We tested for an association between three single nucleotide polymorphisms (SNPs) at the PDLIM5 gene and lithium prophylaxis in a Sardinian sample comprised of ... [Abstract] [Full-text]

Complementary and alternative medicine in the treatment of bipolar disorder - A review of the evidence.   J Affect Disord.

A growing number of patients with mood disorders are using complementary and alternative medicine (CAM) interventions. In this paper, we review the published scientific evidence on the benefits and risks of CAM for the treatment of patients with bipolar disorder. Since very few studies of CAM have involved patients with bipolar disorder, most available evidence is derived from trials conducted in patients with major depressive disorder. The use of omega-3 fatty acids has been studied in two ... [Abstract] [Full-text]

Toxicity of lithium to humans and the environment-A literature review.   Ecotoxicol Environ Saf.

Lithium concentrations in the surface and underground waters may be higher than general environment in places where lithium-rich brines and minerals occur, and in places where lithium batteries are disposed of. This review has indicated that lithium is not expected to bioaccumulate and its human and environmental toxicity are low. Lithium is not a dietary mineral for plants but it does stimulate plant growth. Large doses of lithium (up to 10mg/L in serum) are given to patients with bipolar ... [Abstract] [Full-text]

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