Willem de Haan

Functional network disruption in the degenerative dementias

Despite advances towards understanding the molecular pathophysiology of the neurodegenerative dementias, the mechanisms linking molecular changes to neuropathology and neuropathological changes to clinical symptoms remain largely obscure. Connectivity is a distinctive feature of the brain and the integrity of functional network dynamics is crucial for normal functioning. A better understanding of network disruption in the neurodegenerative dementias might help bridge the gap between molecular changes, pathological changes, and symptoms. Recent findings on functional network disruption as assessed with resting-state or intrinsic connectivity functional MRI and electroencephalography and magnetoencephalography have shown distinct patterns of network disruption across the major neurodegenerative diseases. These network abnormalities are somewhat specific to the clinical syndromes and, in Alzheimers disease and frontotemporal dementia, network disruption tracks the pattern of pathological changes. These findings might have practical implications for diagnostic accuracy, allowing earlier detection of neurodegenerative diseases even at the presymptomatic stage, and tracking of disease progression.

Resting-state oscillatory brain dynamics in Alzheimer disease.

Altered oscillatory brain activity in Alzheimer disease (AD) may reflect underlying neuropathological changes, and its characterization might lead to new diagnostic possibilities. The present study using quantitative magnetoencephalography was set up to examine power spectrum changes in AD patients, and their diagnostic strength. Whole-head 151-channel magnetoencephalography was recorded during an eyes-closed resting state. Magnetoencephalography channels were grouped in 10 cortical regions, and both global and regional relative power was analyzed for the commonly used frequency bands. Eighteen AD patients [mean age 72.1 years ± 5.6 (SD); 7 women; mean Mini Mental State Examination score 19.2, range: 13–25] and 18 healthy controls [mean age 69.1 ± 6.8 (SD), 11 women; mean Mini Mental State Examination score 29, range: 27–30] were recruited, controls being mainly spouses of patients. Relative power analysis showed significant differences in most frequency bands, particularly in the temporo-parietal regions, with some relation to Mini Mental State Examination scores. Greatest diagnostic accuracy was found in the beta band, especially in the right occipital area (sensitivity 94%, specificity 78%). Quantitative relative power analysis of magnetoencephalography recordings is able to show widespread abnormalities in oscillatory brain dynamics in AD patients. By analyzing distinct cortical regions, this study provides a more detailed topographical view of abnormal brain activity in AD.

Strong Relation Between an EEG Functional Connectivity Measure and Postmenstrual Age: A New Potential Tool for Measuring Neonatal Brain Maturation

Fetal and neonatal brain connectivity development is highly complex. Studies have shown that functional networks change dramatically during development. The purpose of the current study was to determine how the mean phase lag index (mPLI), a measure of functional connectivity (FC), assessed with electroencephalography (EEG), changes with postmenstrual age (PMA) during the early stages of brain development after birth. Neonates (N = 131) with PMA 27.6–45.3 weeks who underwent an EEG for a medical reason were retrospectively studied. For each recording, global FC was assessed by obtaining a whole-head average of all local PLI values (pairwise between sensor space EEG signals). Global FC results were consequently correlated with PMA values in seven frequency bands. Local results were obtained for the frequency band with the strongest global association. There was a strong negative correlation between mPLI and PMA in most frequency bands. The strongest association was found in the delta frequency band (R = −0.616, p < 0.001) which was therefore topographically explored; the strongest correlations were between pairs of electrodes with at least one electrode covering the central sulcus. Even in this heterogeneous group of neonates, global FC strongly reflects PMA. The decrease in PLI may reflect the process of segregation of specific brain regions with increasing PMA. This was mainly found in the central brain regions, in parallel with myelination of these areas during early development. In the future, there may be a role for PLI in detecting atypical FC maturation. Moreover, PLI could be used to develop biomarkers for brain maturation and expose segregation processes in the neonatal brain.

Crime’s face: Imagining and representing kleptomania

Marlene Dumas is regarded as one of the most important international painters of this time. In this article, an analysis is made of what her painting The Kleptomaniac (2005) and, in particular, what its title represents. Drawing upon art history, I begin by looking at the original Portrait of a Kleptomaniac (ca. 1820) by Gericault of which Dumas has painted her own version. This will be followed by a discussion of the history of the concept of kleptomania in psychiatry and an analysis of how that concept is reproduced by Dumas’s painting. It will be argued that, by giving the portrait of a man the title of ‘kleptomaniac’ in 2005, Dumas represents a type of criminal in a way that neither does justice to the history of the concept of kleptomania, nor to the phenomenon itself. By mobilizing a contested and obsolete psychiatric concept as a title for a painting, the subject itself is mystified and the effect on the viewer of the painting is not only disorienting, but also ethically problematic.Marlene Dumas is regarded as one of the most important international painters of this time. In this article, an analysis is made of what her painting The Kleptomaniac (2005) and, in particular, what its title represents. Drawing upon art history, I begin by looking at the original Portrait of a Kleptomaniac (ca. 1820) by Géricault of which Dumas has painted her own version. This will be followed by a discussion of the history of the concept of kleptomania in psychiatry and an analysis of how that concept is reproduced by Dumas’s painting. It will be argued that, by giving the portrait of a man the title of ‘kleptomaniac’ in 2005, Dumas represents a type of criminal in a way that neither does justice to the history of the concept of kleptomania, nor to the phenomenon itself. By mobilizing a contested and obsolete psychiatric concept as a title for a painting, the subject itself is mystified and the effect on the viewer of the painting is not only disorienting, but also ethically problematic.