EEG-vigilance differences between patients with borderline personality disorder,patients with obsessive-compulsive disorder and healthy controls

The regulation of brain activation, as assessed with the EEG, is a state modulated trait. A decline to lowered EEG-vigilance states has been found to be associated with emotional instability in older studies, but has not been systematically studied in patients with borderline personality disorder (BPD). Twenty unmedicated BPD patients were compared to 20 unmedicated patients with obsessive-compulsive disorder (OCD) as well as 20 healthy controls concerning their EEG-vigilance regulation over a 5-min period assessed with an algorithm classifying every artefact-free 2-s EEG segment into the EEG-vigilance state (A1–A3, B (=non-A)). If the alpha power was posterior more than 55% of the whole alpha power (anterior + posterior) in the artefact-free EEG-segments, that segment was marked as A1, if it was anterior more than 55% of the whole alpha power, as A3. For A2 the following rule was defined: Posterior or anterior alpha between 50 and 55% of the whole alpha power. BPD patients showed significantly lower rates of EEG-vigilance state A compared to OCD patients, indicating a lowered EEG-vigilance. All three groups showed a decrease in the rate of EEG-vigilance state A over the 5 min recording period in line with a lowering of vigilance. The study provides evidence for a less stable regulation of EEG-vigilance in BPD compared to OCD patients and is in line with concepts postulating that the behavioural pattern with sensation seeking and impulsivity in BPD has a compensatory and autoregulatory function to stabilize activation of the CNS.     

Caloric vestibular stimulation and postural control in patients with spatial neglect following stroke

The impact of spatial neglect remains a substantial challenge to patients undergoing rehabilitation following stroke. Beyond the relatively well-described implications for visuospatial function, neglect is increasingly shown to have a negative impact on the wider aspects of sensori-motor performance with corresponding implications for activities including gait and balance. Caloric vestibular stimulation (CVS) administered to the contralesional ear has previously been shown to improve performance in patients with spatial neglect. Here, in Experiment One, we investigated the effect of CVS on clinical measures of spatial neglect and postural control in three groups of patients following stroke; left brain damaged patients (LBD, n?=?6), right brain damaged patients without neglect (RBD–, n?=?6), and right brain damaged patients with neglect (RBD+?, n?=?6). While post-stimulation scores demonstrated an improvement for participants with spatial neglect, further analysis of postural scores indicated that improvement was selective for asymmetrical activities, with symmetrical activities remaining unchanged. We interpret these results with reference to the related problem of extinction which predicts that activities demanding synchronous bilateral activity (symmetrical activities) would cause greater difficulties for patients with neglect. In Experiment Two, we tested a further six RBD+ patients on the same measures following CVS to the ipsilesional (right) ear. There was no significant improvement in perceptual or postural scores. Our findings are supportive of previous studies that demonstrate improvement in perception and movement for patients with spatial neglect following contralesional CVS and suggest that these improvements may have clinical benefits.     

Correlation between vestibular habituation and postural recovery in cerebellar patients

Vestibular habituation was studied in normal subjects and in patients with cerebellar disease using a stimulation paradigm proposed in this paper. Six caloric stimuli were repeated daily in the same ear during six days and electronystagmographic responses at the beginning and the end of that period were compared. The normal behaviour was a clear reduction of the response across time. Two groups of cerebellar patients were identified by their ability to recover from positional imbalance after treatment. Compensated patients responded to repeated caloric stimulation in the same way as normal subjects. Conversely, uncompensated patients increased their response after the stimulation paradigm. The role played by the cerebellum in vestibular plasticity is discussed together with the observed correlation between vestibular habituation and the ability for postural recovery to occur.     

Relationship between postural control and motion sickness in healthy subjects

This study examined the relationship between reported susceptibility to motion sickness, anxious personality and postural control. Postural stability was assessed in 34 healthy subjects standing with eyes open, eyes closed and viewing a disorienting virtual reality display. These measures were repeated with vibration of the calf muscles to distort the somatosensory feedback from the legs. Susceptibility to motion sickness and anxious personality were evaluated by questionnaire. Greater postural instability was correlated with susceptibility to motion sickness. Motion sickness susceptibility correlated most strongly with increased sway when the visual and somatosensory feedback was absent or distorted. Anxiety was correlated with reported susceptibility to motion sickness but not with postural stability. These findings suggest that deficient perceptual-motor responses to disorienting conditions may contribute to motion sickness susceptibility.     

Dexamethasone suppression test in patients with primary obsessive-compulsive disorder and in healthy controls

The dexamethasone suppression test (DST) was performed in 18 patients (11 women and 7 men) who met the DSM III-R criteria for obsessive-compulsive disorders (OCD), and in 20 healthy volunteers (12 women and 8 men). At 4.00 p.m., following dexamethasone administration, 5 patients (27.7%) and 1 healthy subject (5%) displayed plasma cortisol values well above the cut-off value of 50 ng/dl. A significantly different sex ratio was observed between suppressor and nonsuppressor patients with OCD (chi 2 = 4.40, p less than 0.03), because all nonsuppressor patients were male. Compared to the suppressors, nonsuppressor patients with OCD did not differ in any of the clinical and demographic variables investigated. Moreover, in our patient sample, the mean +/- SD total Hamilton Depression Rating Score (HDRS) was 14.8 +/- 2.5, and none of the nonsuppressors with OCD had a total HDRS greater than 17. These data suggest that a subgroup of OCD patients, particularly males, may escape the DST independently from the coexistence of depressive features.     

Reduced postural differences between phobic postural vertigo patients and healthy subjects during a postural threat

Phobic postural vertigo is characterized by subjective imbalance and dizziness while standing or walking, despite normal values for clinical balance tests. Patients with phobic postural vertigo exhibit an increased high-frequency sway in posturographic tests. Their postural sway, however, becomes similar to the sway of healthy subjects during difficult balance tasks. Posturographic recordings of 30 s of quiet stance was compared to recordings of 30 s of quiet stance during a postural threat, which consisted of the knowledge of forthcoming vibratory calf muscle stimulation, in 37 consecutive patients with phobic postural vertigo and 24 healthy subjects. During quiet stance without the threat of forthcoming vibratory stimulation, patients with phobic postural vertigo exhibited a postural sway containing significantly more high-frequency sway than the healthy subjects. During the quiet stance with forthcoming vibratory stimulation, i.e., anticipation of a postural threat, the significant differences between groups disappeared for all variables except sagittal high-frequency sway. During postural threat, healthy subjects seemed to adopt a postural strategy that was similar to that exhibited by phobic postural vertigo patients. The lack of additional effects facing a postural threat among phobic postural vertigo patients may be due to an already maximized postural adaptation. Deviant postural reactions among patients with phobic postural vertigo may be considered as an avoidant postural response due to a constant fear of losing postural control.     

Interference control commonalities in patients with schizophrenia,bipolar disorder,and borderline personality disorder

Background: Whereas deficits in executive functioning have been widely reported in schizophrenia and, somewhat less, in bipolar disorder, few studies have addressed this issue in people diagnosed with borderline personality disorder. Importantly, no studies to date have compared the ability to cope with interfering information in all three groups of patients. Impairment in executive control has been associated with reduced daily functioning. Method: The sample included 20 patients diagnosed with schizophrenia, 19 with bipolar disorder, 20 with borderline personality disorder, and 19 demographically matched healthy volunteers. Participants were administered two different experimental tasks to assess the ability to exert control over interference arisen from semantic memory or from distracting perceptual information. Results: The three groups of patients showed similar impairment in solving interference from semantic memory compared to controls. However, no psychiatric group showed impairment in controlling interference from distracting perceptual information relative to controls. Conclusions: Our study shows, for the first time, that schizophrenia, bipolar disorder, and borderline personality disorder entail a common impairment in exerting control over interference arisen from memory but intact control over perceptual interference. These findings reinforce the idea that similar cognitive functioning may underlie severe mental disorders sharing poor global functioning but with different patterns of symptomatology.     

CSF-hypocretin-1 levels in patients with major depressive disorder compared to healthy controls

Depressive patients exhibit symptoms of impaired regulation of wakefulness with hyperarousal and agitation as well as difficulties to falling asleep and preserving sleep continuity. Changes in hypocretin (hcrt) levels as polypeptides with impact on arousal and sleep-wake-regulation have been discussed in affective disorders but have not been investigated in patients with solely unipolar depression in comparison to healthy controls. In the present study, cerebrospinal fluid (CSF) levels of hcrt-1 for the first time were analyzed in patients with major depressive disorder (MDD) without psychiatric comorbidities and compared with levels in healthy controls. In 17 inpatients with MDD (mean Hamilton Depression Rating Scale 13.9 ± 7.4) and 10 healthy controls, CSF-hcrt-1 levels were measured using a fluorescence immunoassay (FIA). The mean hcrt-1 CSF levels in patients with MDD (74.3 ± 17.8pg/ml) did not differ compared to that of healthy controls (82.8 ± 22.1pg/ml). Hcrt-1 levels did not correlate with the severity of depressive episode, the symptoms of depression or the number of episodes. Although autonomic and neurohumoral signs of hyperarousal are common in MDD, hcrt-1 levels in CSF were not found to be altered in MDD compared to healthy controls. Whether hcrt-1 levels are altered in depressive patients exhibiting impaired vigilance regulation has to be investigated in further studies combining measures of CSF-hcrt-1 with electroencephalography.     

The association between antisaccade task and working memory task performance in schizophrenia and bipolar disorder

To date, the research literature has yielded conflicting reports regarding the specificity of antisaccade deficits to schizophrenia. We sought to examine antisaccade and working memory task performance in schizophrenia patients and bipolar patients, as well as to examine the relationship between the two tasks in both patient populations. Thirty-four schizophrenia patients, 20 bipolar patients, and 30 nonpatient controls were administered saccadic inhibition (antisaccade), working memory, and sensorimotor tasks. Compared with the controls, the schizophrenia patients displayed both antisaccade deficits and working memory deficits. In contrast, the bipolar patients produced significantly more errors on the antisaccade task than the controls, though the bipolar group performed similarly to the control group on the working memory task. Mediational analyses demonstrated that working memory partially mediates the relationship between patients' diagnostic group status and antisaccade task performance; working memory performance contributed uniquely to the prediction of antisaccade task performance in the two patient groups. Antisaccade deficits do not appear specific to schizophrenia. The results suggest that in schizophrenia, working memory and antisaccade tasks are tapping similar cognitive processes, whereas in bipolar patients the processes underlying antisaccade and working memory performance are disparate.     

Serotonergic responsivity in obsessive-compulsive disorder. Comparison of patients and healthy controls

To examine the "serotonin hypothesis" of obsessive-compulsive disorder (OCD), we studied the behavioral and neuroendocrine effects of metachlorophenylpiperazine (mCPP), a serotonergic agonist, in patients with OCD and healthy controls. Twelve patients and 20 controls were given a single dose of 0.5 mg/kg of mCPP, administered orally under double-blind, placebo-controlled, random-assignment conditions. Following mCPP, but not following placebo, patients with OCD experienced a transient but marked exacerbation of obsessive-compulsive symptoms. Moreover, compared with healthy controls, patients exhibited greater other behavioral (but not endocrinologic or thermal) changes after mCPP. These findings are consistent with a special role for the neurotransmitter serotonin in OCD psychopathology.     

EEG coherence in a mental arithmetic task performance in first episode schizophrenia and schizoaffective disorder

Objectives

To evaluate the coherence values of the cortical bands in patients with first episode schizophrenia and schizoaffective disorder during the performance of a mental arithmetic task.

Grip force control in patients with neck and upper extremity pain and healthy controls

OBJECTIVE: To investigate whether sensory and motor problems in patients with non-specific neck and upper extremity pain can be ascribed to a deficit of sensory-motor integration. METHODS: Grip force control and adaptation were measured in 81 cases, 32 former cases and 39 healthy controls, during repetitive lifting and holding of an object. The object (300 g) was lifted vertically over 20 cm and held for 5s, using the dominant arm (the affected arm in all cases). The object was novel to the subjects when lifted for the first time, and was lifted five times consecutively. Grip forces orthogonal to the object's surface and its vertical acceleration were measured. RESULTS: Cases used significantly higher grip forces than both other groups, while vertical acceleration was not different. After the initial lift, all groups significantly reduced the maximum grip force. CONCLUSIONS: Subjects with neck and upper extremity pain consistently use higher grip forces than controls, but adjust grip forces by a similar amount after the first lift. Compensation of impaired sensory information rather than a general deficit in sensory-motor integration seems to account for these findings. SIGNIFICANCE: Non-specific neck and upper extremity pain coincides with objectifiable changes in control of grip force.     

Self-report and laboratory measures of impulsivity in patients with schizophrenia or schizoaffective disorder and healthy controls

This study examined self-reported impulsivity and aggression and performance on the stop-signal task in patients with schizophrenia or schizoaffective disorder and healthy volunteers. Compared to controls, patients had higher scores on interview and questionnaire measures of impulsivity and aggression and showed increased stop-signal reaction time and greater response variability. These findings are consistent with a specific impairment in response inhibition in schizophrenia.     

Visuomotor performance of schizophrenic patients and normal controls in a picture viewing task

The eye movements of 20 partially remitted schizophrenic outpatients (ICD-9) under neuroleptic maintenance medication and those of 20 normal controls were recorded using corneal reflection pupil-center measurement. The visuomotor performance during a 1-min picture viewing task was studied on the basis of several eye movement parameters. Clinical evaluation comprised self-ratings (Frankfort Complaint Questionnaire) and observer ratings (BPRS, CGI, GAS), as well as recording of current daily neuroleptic dosage (mg CPZ). The main results are that schizophrenics differ from normals in their correlational pattern of fixation- and movement-related parameters, reflecting two opposite viewing styles in schizophrenics: staring and extensive scanning. Both styles are differently related to clinical symptomatology. There was no strongly marked relationship with neuroleptic dosage.     

Effects of perceptible and imperceptible galvanic vestibular stimulation on the postural control of patients with bilateral vestibulopathy

Journal of Neurology - Galvanic vestibular stimulation (GVS) has increasingly been used to stimulate the vestibular system in health and disease. While perceptible supra-threshold GVS destabilizes...     

Mood regulation in seasonal affective disorder patients and healthy controls studied in forced desynchrony

In healthy subjects, both the duration of wakefulness and the circadian pacemaker have been demonstrated to be involved in the regulation of mood. Some features of affective disorders suggest that these two factors also play a role in the dysregulation of mood. In particular, disturbances of the circadian pacemaker have been proposed to be a pathogenetic factor in Seasonal Affective Disorder, winter type (SAD). This report presents a test of this proposition. To this end seven SAD patients and matched controls were subjected to a 120-h forced desynchrony protocol, in which they were exposed to six 20-h days. This protocol enables us to discriminate the extent to which the course of mood is determined by the imposed 20-h sleep-wake cycle from the influence of the circadian pacemaker on that course. Patients participated during a depressive episode, after recovery upon light therapy and in summer. Controls were studied in winter and in summer. Between SAD patients and controls no significant differences were observed in the period length nor in the timing of the endogenous circadian temperature minimum. In both groups, sleep-wake cycle- and pacemaker-related components were observed in the variations of mood, which were not significantly different between conditions.     

A caffeine challenge test in panic disorder patients, their healthy first-degree relatives, and healthy controls

Our aim was to observe the induction of anxiety symptoms and panic attacks by a caffeine challenge test in panic disorder (PD) patients (DSM-IV) and their healthy first-degree relatives. We randomly selected 25 PD patients, 27 healthy first-degree relatives of probands with PD, and 22 healthy volunteers with no family history of PD. In a randomized double-blind experiment performed over two occasions 7 days apart, 480 mg caffeine and a caffeine-free solution were administered in a coffee form. Using specific panic attack criteria, 52.0% (n=13) PD patients, 40.7% (n=11) first-degree relatives (chi2=1.81, df=1, P=0.179), and none of the control subjects had a panic attack after the test (chi2=51.7, df=2, P<0.001). In this caffeine challenge test, PD patients and their first-degree relatives were more sensitive than healthy volunteers to the panic attack symptoms but less sensitive to headache, increase in blood pressure, and insomnia. Our data suggest that there is an association between panic attacks after the intake of 480 mg of caffeine in PD patients and their first-degree relatives. There is a clear differentiation of PD patients and their first-degree relatives by a caffeine test from the healthy group.     

Cognitive deficits in patients with chronic fatigue syndrome compared to those with major depressive disorder and healthy controls

Object

Chronic fatigue syndrome (CFS) patients report usually cognitive complaints. They also have frequently comorbid depression that can be considered a possible explanation for their cognitive dysfunction. We evaluated the cognitive performance of patients with CFS in comparison with a control group of healthy volunteers and a group of patients with MDD.

Patients and methods

Twenty-five patients with CFS, 25 patients with major depressive disorder (MDD), and 25 healthy control subjects were given standardized tests of attention, working memory, and verbal and visual episodic memory, and were also tested for effects related to lack of effort/simulation, suggestibility, and fatigue.

Results

Patients with CFS had slower phasic alertness, and also had impaired working, visual and verbal episodic memory compared to controls. They were, however, no more sensitive than the other groups to suggestibility or to fatigue induced during the cognitive session. Cognitive impairments in MDD patients were strongly associated with depression and subjective fatigue; in patients with CFS, there was a weaker correlation between cognition and depression (and no correlation with fatigue).

Conclusions

This study confirms the presence of an objective impairment in attention and memory in patients with CFS but with good mobilization of effort and without exaggerated suggestibility.