To send content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about sending content to .
To send content items to your Kindle, first ensure email@example.com
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about sending to your Kindle.
Note you can select to send to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Metacognitive knowledge (MK; general awareness of cognitive functioning) and metacognitive experience (ME; awareness of cognitive performance on a specific cognitive task) represent two facets of metacognition that are critical for daily functioning, but are understudied in bipolar disorder. This study was conducted to evaluate MK and ME across multiple cognitive domains in individuals diagnosed with bipolar disorder and unaffected volunteers, and to investigate the association between metacognition and quality of life (QoL).
Fifty-seven euthymic participants with bipolar disorder and 55 demographically similar unaffected volunteers provided prediction and postdiction ratings of cognitive task performance across multiple cognitive domains. Self-ratings were compared to objective task performance, and indices of MK and ME accuracy were generated and compared between groups. Participants rated QoL on the Quality of Life in Bipolar Disorder Scale (QoL.BD).
Metacognitive inaccuracies in both MK and ME were observed in participants with bipolar disorder, but only in select cognitive domains. Furthermore, most metacognitive inaccuracies involved underestimation of cognitive ability. Metacognitive indices were minimally associated with medication variables and mood symptoms, but several indices were related to QoL.
Individuals with bipolar disorder demonstrate inaccuracies in rating their cognitive functioning and in rating their online cognitive task performance, but only on select cognitive functions. The tendency to underestimate performance may reflect a negative information processing bias characteristic of mood disorders. Metacognitive variables were also predictive of QoL, indicating that further understanding of cognitive self-appraisals in persons with bipolar disorder has significant clinical relevance.
We previously reported that bipolar disorder (BD) patients with clinically significant weight gain (CSWG; ⩾7% of baseline weight) in the 12 months after their first manic episode experienced greater limbic brain volume loss than patients without CSWG. It is unknown whether CSWG is also a risk factor for progressive neurochemical abnormalities.
We investigated whether 12-month CSWG predicted greater 12-month decreases in hippocampal N-acetylaspartate (NAA) and greater increases in glutamate + glutamine (Glx) following a first manic episode. In BD patients (n = 58) and healthy comparator subjects (HS; n = 34), we measured baseline and 12-month hippocampal NAA and Glx using bilateral 3-Tesla single-voxel proton magnetic resonance spectroscopy. We used general linear models for repeated measures to investigate whether CSWG predicted neurochemical changes.
Thirty-three percent of patients and 18% of HS experienced CSWG. After correcting for multiple comparisons, CSWG in patients predicted a greater decrease in left hippocampal NAA (effect size = −0.52, p = 0.005). CSWG also predicted a greater decrease in left hippocampal NAA in HS with a similar effect size (−0.53). A model including patients and HS found an effect of CSWG on Δleft NAA (p = 0.007), but no diagnosis effect and no diagnosis × CSWG interaction, confirming that CSWG had similar effects in patients and HS.
CSWG is a risk factor for decreasing hippocampal NAA in BD patients and HS. These results suggest that the well-known finding of reduced NAA in BD may result from higher body mass index in patients rather than BD diagnosis.
To evaluate an abbreviated NIH Toolbox Cognition Battery (NIHTB-CB) protocol that can be administered remotely without any in-person assessments, and explore the agreement between prorated scores from the abbreviated protocol and standard scores from the full protocol.
Participant-level age-corrected NIHTB-CB data were extracted from six studies in individuals with a history of stroke, mild traumatic brain injury (mTBI), treatment-resistant psychosis, and healthy controls, with testing administered under standard conditions. Prorated fluid and total cognition scores were estimated using regression equations that excluded the three fluid cognition NIHTB-CB instruments which cannot be administered remotely. Paired t tests and intraclass correlations (ICCs) were used to compare the standard and prorated scores.
Data were available for 245 participants. For fluid cognition, overall prorated scores were higher than standard scores (mean difference = +4.5, SD = 14.3; p < 0.001; ICC = 0.86). For total cognition, overall prorated scores were higher than standard scores (mean difference = +2.7, SD = 8.3; p < 0.001; ICC = 0.88). These differences were significant in the stroke and mTBI groups, but not in the healthy control or psychosis groups.
Prorated scores from an abbreviated NIHTB-CB protocol are not a valid replacement for the scores from the standard protocol. Alternative approaches to administering the full protocol, or corrections to scoring of the abbreviated protocol, require further study and validation.
We previously reported that patients with early-stage bipolar disorder,
but not healthy comparison controls, had body mass index (BMI)-related
volume reductions in limbic brain areas, suggesting that the structural
brain changes characteristic of bipolar disorder were more pronounced
with increased weight.
To determine whether the most consistently reported neurochemical
abnormality in bipolar disorder, increased glutamate/glutamine (Glx), was
also more prominent with higher BMI.
We used single-voxel proton magnetic resonance spectroscopy to measure
hippocampal Glx in 51 patients with first-episode mania (mean BMI = 24.1)
and 28 healthy controls (mean BMI = 23.3).
In patients, but not healthy controls, linear regression demonstrated
that higher BMI predicted greater Glx. Factorial ANCOVA showed a
significant BMI×diagnosis interaction, confirming a distinct effect of
weight on Glx in patients.
Together with our volumetric studies, these results suggest that higher
BMI is associated with more pronounced structural and neurochemical
limbic brain changes in bipolar disorder, even in early-stage patients
with low obesity rates.
This paper focus on evaluating the ability to use Mexican fly ash (FA) and copper slag (CS) to produce alkali cements (0% OPC) or hybrid cements (20% OPC + 80% fly ash). The alkali activators used were two: 8 M NaOH solution for alkali cements and NaCl with sodium silicate for hybrid cement (HYC). Results of mechanical testing and characterization of the reaction products formed after 2 and 28 days are presented and discussed. Mechanical strength in some cases exceeded 20 MPa, at 2 days curing. The chemical characterization techniques used were X-Ray Diffraction (XRD) and scanning electron microscopy (SEM).
Although manic episodes reportedly contribute to cognitive deficits in bipolar I disorder, the contribution of depressive episodes is poorly researched.
We investigated the impact of depressive episodes on cognitive function early in the course of bipolar I disorder.
A total of 68 patients and 38 controls from the Systematic Treatment Optimization Programme for Early Mania (STOP-EM) first-episode mania programme were examined. We conducted (a) a cross-sectional analysis of the impact of prior depressive episodes on baseline cognitive function and (b) a prospective analysis assessing the contribution of depression recurrence within 1 year following a first episode of mania on cognitive functioning.
The cross-sectional analysis showed no significant differences between patients with past depressive episodes compared with those without, on overall or individual domains of cognitive function (all P>0.09). The prospective analysis failed to reveal a significant group×time interaction for cognitive decline from baseline to 1 year (P = 0.99) in patients with a recurrence of depressive episodes compared with those with no recurrence. However, impaired verbal memory at baseline was associated with a depression recurrence within 1 year.
Although deficits in all domains of cognitive function are seen in patients early in the course of bipolar disorder, depressive episodes do not confer additional burden on cognitive function. However, poorer verbal memory may serve as a marker for increased susceptibility to depression recurrence early in the course of illness.
Schizophrenia spectrum patients (N = 143) and
healthy controls (N = 160) were administered the
Rey Auditory Verbal Learning Test (RAVLT) and tests of
executive functioning to directly investigate the effects
of proactive interference (PI) and retroactive interference
(RI) on word list recall. It was hypothesized that by virtue
of the predicted preferential association between executive
functioning and RI (relative to PI), patients would demonstrate
increased susceptibility to RI in their ability to recall
word lists. Results indicated that patients show increased
susceptibility to RI relative to PI. Furthermore, this
difference appeared to be related to the frontally-mediated
central executive functions that were preferentially associated
with RI but not PI susceptibility. (JINS, 2001,
Email your librarian or administrator to recommend adding this to your organisation's collection.