Evidence of language-related left hypofrontality in Major Depression: An EEG Beta band study

Major depression (MDD) has been associated with an altered EEG frontal asymmetry measured in resting state; nevertheless, this association has showed a weak consistency across studies. In the present study, which starts from an evolutionistic view of psychiatric disorders, we investigated frontal asymmetry in MDD, using language as a probe to test the integrity of large inter- and intra-hemispheric networks and processes. Thirty MDD patients (22 women) and 32 matched controls (HC) were recruited for an EEG recording in resting state and during two linguistic tasks, phonological and semantic. Normalized alpha and beta EEG spectral bands were measured across all three conditions in the two groups. EEG alpha amplitude showed no hemispheric asymmetry, regardless of group, both at rest and during linguistic tasks. During resting state, analysis of EEG beta revealed a lack of hemispheric asymmetry in both groups, but during linguistic tasks, HC exhibited the typical greater left frontal beta activation, whereas MDD patients showed a lack of frontal asymmetry and a significantly lower activation of left frontal sites. In depressed patients, positive affect was negatively correlated with depression levels and positively correlated with left frontal EEG beta amplitude. Language represents the human process that requires the largest level of integration between and within the hemispheres; thus, language asymmetry was a valid probe to test the left frontal alteration encompassing highly impairing psychiatric disorders, such as schizophrenia and MDD. Indeed, these severe diseases are marked by delusions, ruminations, thought disorders, and hallucinations, all of which have a clear linguistic or metalinguistic basis.

Reduced right posterior hippocampal volume in women with recurrent familial pure depressive disorder

Volumetric changes in mood-relevant distributed limbic/paralimbic structures have been reported in the recent literature on the course of mood disorders. Patients with unipolar and bipolar disorders have been found to have smaller hippocampal and anterior cingulate volumes. We examined hippocampal, amygdalar and anterior cingulate cortex (ACC) volumes in female patients with recurrent familial pure depressive disorder (rFPDD). We used semi-automated software for magnetic resonance imaging (MRI) to measure the volumes of the hippocampus, amygdala, ACC and subgenual prefrontal cortex (SGPFC) in 15 female patients with familial recurrent major depression (MD) and 15 healthy female subjects. Analysis of covariance, with whole brain volume as covariate, was used to compare volumetric measurements in the two groups. Volumes of the right hippocampal body and tail were significantly smaller in female patients with familial depressive disorder than in healthy subjects. Our data provide evidence of structural lateralized hippocampal body and tail abnormalities in women with familial history and recurrent episodes of depression. Although global reduction of hippocampal volume has been widely reported, data on lateralized regional reductions in familial recurrent depression had not been previously reported. Reduced volume of the right posterior hippocampus could be a structural endophenotype for recurrent depressive disorders in women.

Circadian variations of sinus rate in subjects with sinus node dysfunction

Circadian variations of sinus rate (SR) are well described in subjects with normal sinus node (SN). On the other hand there are no data in literature concerning the SR daily variations in patients with SN dysfunction. In order to clarify this problem we studied the SR circadian variation in healthy subjects (12) and in patients with intermittent bradycardia (11), persistent bradycardia (9) and intermittent 2:1 sino-atrial block (7). Sr was recorded utilizing ECG Holter monitoring. By histograms obtained every 2 h, maximum, modal, and minimum SR were evaluated. Time series were analyzed with a computer program for cosinor method. In the patients with normal SN, circadian periodicity in SR was confirmed with acrophase at 16(26) (Maximum SR), 16(38) (minimum SR) and 16(31) (SR mode), respectively. In patients with intermittent bradycardia a circadian rhythm was detected only in minimum SR (Acrophase: 16(51)) and in SR mode (acrophase: 16(13)). No statistically significant circadian variations of the 3 parameters of SR were observed in patients with both persistent bradycardia and sino-atrial block. These data suggest that: 1. the disappearance of the circadian periodicity is proportional to the severity of SN dysfunction; 2. the patients with intermittent bradycardia show a more normal behavior at low rates than at high ones; 3. the disappearance of circadian rhythm in patients with marked SN dysfunction can be related to the SN intrinsic involvement and/or autonomic nervous system dysfunction.

Disorders in peripheral arterial system in asymptomatic elderly: plethysmographic semiology at rest, during postural, effort and pharmacological tests

The vascular system of 30 old asymptomatic patients (average age 62.5 years) was studied by reflection plethysmography. The plethysmogram (PTG) was recorded from the forefinger of the left hand at rest, during two postural tests (+45 degrees arm-up and -45 degrees arm-down), after physical work, and during the infusion of nitroglycerin and the beta-agonist metaproterenol. 50% of the subjects presented a normal PTG under basal conditions. However, pathological PTGs were recorded after the various tests: 23.3% with the arm-up test, 6.6% with the arm-down test, 52% with the effort test, 31% with the nitroglycerin test and 73.9% with the metaproterenol test. Clearly, the effort and metaproterenol tests are pathological in the majority of cases, both tests inducing physiologically vasodilation and increase in the peripheral pulse. The arm-down test, which usually induces vasoconstriction, is almost always normal. Since the percentage of pathological responses to the nitroglycerin test is significantly smaller than that to the effort and metaproterenol tests, it is concluded that the vascular changes induced by aging are primarily functional, at least in asymptomatic subjects. Aging more negatively influences the vasodilating than the vasoconstricting ability.