Biomedical subjects

Jens Blechert

Publications and source records attributed to Jens Blechert.

3 recordsLinked to original sources

PubMed2006

Identifying anxiety states using broad sampling and advanced processing of peripheral physiological information.

Advances in biosignal acquisition and processing have provided an effective window to the complex peripheral physiology related to human emotions. Numerous cardiovascular measures have been used for assessing the activity of the sympathetic and parasympathetic branches of the autonomic nervous system. More recently, respiratory parameters have shown promise for the assessment of anxiety. Current theoretical accounts of anxiety recommend a broad assessment of anxiety responses involving measures from the physiological, behavioral and verbal-cognitive domain. However, practical and statistical considerations put restrictions on the number of dependent variables used in studies on emotion. In a laboratory experiment we assessed a large number of psychophysiological parameters to identify their relative utility for differentiating between a neutral (quiet sitting) and an anxious state induced by threat of shock. High effect sizes were found in all psychophysiological systems with electrodermal and behavioral responses demonstrating the highest, and respiratory and cardiovascular responses yielding medium and small effect sizes. A linear combination of the six most powerful variables was highly significant in distinguishing the neutral from the anxious state and resulted in 83.3% correct classification. Results demonstrate the necessity to include measures from multiple response domains for an adequate assessment of anxiety states. Furthermore, our results point to the significance of respiratory parameters in anxiety assessment.

Adult↗

PubMed2005

Are there attentional deficits in people putatively at risk for affective disorders?

BACKGROUND: Schizophrenia is associated with attentional dysfunctions. In bipolar disorder, there is also evidence for sustained attention deficits. Therefore, we hypothesized that risk for bipolar disorder but not for unipolar depression might be associated with attentional abnormalities as well. METHOD: Using the Hypomanic Personality Scale (HPS) and the Rigidity Scale, we defined three groups: bipolar at-risk (n=42), unipolar at-risk (n=34), and control (n=37). All completed the d2 Test and the Continuous Performance Test (CPT). RESULTS: There was no evidence for overall attentional deficits in people at risk for affective disorders. However, reduced sensitivity, i.e., less discrimination between targets and nontargets, was observed in people at risk for bipolar disorders who also displayed schizotypy. LIMITATIONS: We only looked at selective and sustained attention and did not assess other factors such as memory or executive functions. Additionally, the risk status was only defined by a psychometric indicator and did not include other approaches of defining risk (e.g., first-degree relatives). CONCLUSIONS: Despite some limitations, our results support on one hand the idea that vulnerability for bipolar disorder can be associated with cognitive impairments, but they also highlight that this is not generally the case. Vulnerability for bipolar disorder and schizotypy might be correlated but are not the same.

Adolescent↗

PubMed2005

Are measures of hypomanic personality, impulsive nonconformity and rigidity predictors of bipolar symptoms?

OBJECTIVES: It has been suggested that temperaments such as 'hypomanic personality' (HYP) have an explanatory role in affective disorders. Similarly, the impulsive nonconformity scale, originally designed to assess psychosis proneness, was recently found to augment the prediction of manic episodes. Conversely, research indicates that 'rigidity', a central feature of Typus Melancholicus (TMEL; von Zerssen, 1996), may characterize the premorbid personality of depressives. DESIGN: The present study combines these three scales to prospectively predict manic and depressive symptoms diagnosed 2 years later in a non-college student population. METHOD: Structured clinical interviews for DSM-IV were conducted with 114 individuals (60% female, mean age = 19 . 9 years), 2 years after an initial screening. RESULTS: It was found that none of the predictors predicted purely depressive symptoms. As expected, HYP emerged as the strongest predictor of (hypo-)manic symptoms. CONCLUSIONS: While rigidity did not predict depression, people with a hypomanic temperament are at risk of developing symptoms of bipolar disorder, especially (hypo-)manic ones. It is noteworthy that this was evident in our young sample, still in the earlier stages of the high-risk period.

Adult↗