[Can psychopathy be detected psychophysiologically?]. / Ist Psychopathie psychophysiologisch fassbar?

The aim of the present study was to determine whether pupillometry was able to identify and differentiate psychopathic personality traits in criminally responsible mentally disordered offenders (§ 21/2 StGB). Psychopathic disorder has not only behavioral, but also psychophysiological correlates, which may be evaluated by pupillometry. This might make it possible to diagnose psychopathy by means of a non-invasive method and in a further step to adapt therapeutic measures accordingly. Psychopathic behavior and personality traits were identified by means of the Hare Psychopathy Checklist-Revised (PCL-R) and offenders were divided into 4 groups with PCL-R scores of 0-10, 11-20, 21-30 and 31-40, respectively. Pupillometry makes it possible to objectively measure amplitudes of pupillary oscillations, which may serve as an indicator of central nervous activation/deactivation. The study at hand showed that the higher the PCL-R values, the smaller the amplitudes. Thus, it can be concluded that central nervous activation decreases with higher PCL-R values and psychopathy is associated with central nervous deactivation.

[Does the duration of confinement of criminally responsible mentally disordered offenders (§ 21/2 StGB) play a role in the development of a functional psychosyndrome? - A pupillometric investigation]. / Spielt die Haftdauer von Untergebrachten gemäß § 21/2 StGB eine Rolle in Bezug auf die Entstehung eines funktionellen Psychosyndroms? - Eine Untersuchung mittels der Methode der Pupillometrie.

BACKGROUND: Pupillometry is a non-invasive investigation based on the concept that pupillary reagibility depends on a number of specific sensory, mental and emotional variables. By means of the receptor test based on the topical application of the cholinergic antagonist tropicamide cognitive deficits can be evaluated. The present study focuses on the question whether the receptor test is able to differentiate criminally responsible mentally disordered offenders (§ 21/2 StGB) with different durations of confinement concerning the presence of a functional psychosyndrome, as defined by Grünberger. METHODS: Four groups of offenders with different durations of confinement (group A: confinement 0-2 years, n = 26, X = 33; group B: 2-5 years, n = 29, X = 34; group C: 5-10 years, n = 6, X = 36; group D: >10 years, n = 10, X = 43) were investigated by means of a computer-assisted TV pupillometer. After a baseline measurement 0.01% tropicamide was instilled into the eye. The second measurement was conducted 20 min after the first, the 3rd and 4th measurements in intervals of 20 min. RESULTS: The groups with a longer duration of confinement showed a reduced activation and vigilance and increased fatigability as compared with the groups of shorter confinement. In the receptor test the group that had been imprisoned for 0-2 years showed more cognitive deficits than those imprisoned for ≥5 years. CONCLUSIONS: Evaluation of activation, fatigability and vigilance indicates that the duration of confinement plays a role in the development of a functional psychosyndrome. The results of the receptor test, in which the group with a longer duration of confinement showed less pronounced cognitive deficits and no significant changes of the tropicamide effect over time, suggest that in this group a dose change might be required to make the cognitive deficits evident.

[The pupillary response test as a method to differentiate various types of dementia]. / Der Rezeptortest bei der Pupillometrie als Methode zur Differenzierung des dementiellen Syndroms.

AIM: Pupillometry is a non-invasive measurement technique based on the pupillary response to specific sensoric, mental and emotional variables. After topical application of a cholinergic antagonist (tropicamide) an increased pupillary dilatation response in Alzheimers s disease patients was described ("receptor test"). The aim of the present study was to evaluate the usefulness of the 0.01% tropicamide receptor test in differentiating types of dementia. METHOD: 425 patients (159 men, 266 women, mean age 75 years) of the Memory Clinic of the SMZ Ost Vienna, Austria were included in the study. 195 patients suffered from a dementia in Alzheimer's disease with late onset (ICD-10: F00.1), 42 from dementia in Alzheimer's disease with early onset (F00.0), 71 from vascular dementia (F01), 34 from Lewy-Body dementia (F03) and 83 from mixed dementia (F00.2). All patients were investigated by means of a computer-assisted pupillometer. The pupillary diameter of the left eye was measured 4 times (baseline=0 minutes, after 20, 40 and 60 minutes). 4 minutes after baseline one drop of 0.01% tropicamide solution was installed onto the left eye of the patients. RESULTS: At baseline the pupillary diameter was largest in Lewy-Body dementia, smallest in vascular dementia. Significant differences were observed between vascular dementia and early-onset dementia in Alzheimer's disease as well as between Lewy-Body dementia and all other dementia syndromes (except dementia in Alzheimer's disease with early onset). The 0.01% tropicamide receptor test made it possible to differentiate early-onset dementia in Alzheimer's disease from vascular and mixed dementia. CONCLUSION: Utilizing pupillometry in combination with the 0.01% tropicamide receptor test allows to discriminate between different dementia types of, as demonstrated in our study.

Rotational thromboelastography for monitoring of fibrinogen concentrate therapy in fibrinogen deficiency.

To characterize a functional assay for circulating fibrinogen based on rotational thrombelastography. Maximum clot firmness was determined by rotational thrombelastography in normal human plasma pool, fibrinogen-deficient plasma pool, normal whole blood, and individual plasma samples from 17 patients with fibrinogen deficiency. Plasma samples spiked with varying concentrations of exogenous fibrinogen were also measured. Results were compared with enzyme-linked immunosorbent assay and Clauss assay. The impact of sample freezing and filtration and use of cytochalasin D were also investigated. Over the tested range of 0-3 mg/ml added exogenous fibrinogen, the maximum clot firmness standard curve for determination of fibrinogen in plasma pools (n = 7) was linear (r2 = 0.97). Maximum clot firmness was highly linearly correlated both with Clauss assay (r2 = 0.93) and enzyme-linked immunosorbent assay (r2 = 0.95). In unspiked plasma samples from individual patients with fibrinogen deficiency, fibrinogen was undetectable by rotational thromboelastography. By all evaluated methods, the response to spiking with fibrinogen in such samples coincided closely in patients with afibrinogenemia and hypofibrinogenemia. In dysfibrinogenemia, smaller Clauss assay responses to spiking were observed, whereas the enzyme-linked immunosorbent assay response was variable. Maximum clot firmness was the only evaluated method of fibrinogen assessment to yield consistent results across all categories of fibrinogen deficiency. These in-vitro results suggest the potential clinical utility of rotational thromboelastography as a versatile method for monitoring the response to fibrinogen concentrate among patients with fibrinogen deficiency. Clinical investigations using rotational thromboelastography after in-vivo fibrinogen administration to patients with congenital fibrinogen deficiency are warranted.

Reaction to pain stimulus before and during hypnosis measured by pupillary reaction.

The aim of this study was to investigate the analgesic effects of hypnotic pain control on experimental pain by measuring pupil reactions as an objective psycho-physiologic parameter. Twenty-two healthy volunteers (11 female and 11 male) aged between 22 and 35 years participated in the study. Pupil diameter was measured as baseline measurement (i.e., static measurement) in the non-hypnotic and in the hypnotic state. Pupil diameter changes to a standardized pain stimulus were measured in the non-hypnotic and hypnotic state and compared. Additionally, a Fourier analysis of pupil oscillations reflecting central nervous activation during the static measurement (25.6 sec) was calculated. During the hypnotic state the pain related pupil dilation was significantly smaller than during the non-hypnotic state. Pupil oscillations were significantly reduced during hypnosis.

Denervated muscles in humans: limitations and problems of currently used functional electrical stimulation training protocols.

Prior clinical work showed that electrical stimulation therapy with exponential current is able to slow down atrophy and maintain the muscle during nonpermanent flaccid paralysis. However, exponential currents are not sufficient for long-term therapy of denervated degenerated muscles (DDMs). We initiated a European research project investigating the rehabilitation strategies in humans, but also studying the underlying basic scientific knowledge of muscle regeneration from satellite cells or myoblast activity in animal experiments. In our prior study, we were able to show that high-intensity stimulation of DDMs is possible. At the beginning of training, only single muscle twitches can be elicited by biphasic pulses with durations of 120-150 ms. Later, tetanic contraction of the muscle with special stimulation parameters (pulse duration of 30-50 ms, stimulation frequency of 16-25 Hz, pulse amplitudes of up to 250 mA) can improve the structural and metabolic state of the DDMs. Because there are no nerve endings for conduction of stimuli, large-size, anatomically shaped electrodes are used. This ensures an even contraction of the whole muscle. Contrary to the current clinical knowledge, we were able to stimulate and train denervated muscle 15-20 years after denervation. The estimated amount of muscle fibers that have to be restored is about 2-4 million fibers in each m. quadriceps. To rebuild such a large number of muscle fibers takes up to 3-4 years. Despite constant stimulation parameters and training protocols, there is a high variation in the developed contraction force and fatigue resistance of the muscle during the first years of functional electrical stimulation.

A stimulator for functional activation of denervated muscles.

In recent years various studies proved that electrical stimulation can improve contractile capability and restore muscle function in long-term denervated degenerated muscles. The low excitability of the muscle cells at the initial stage of training and surrounding connective tissue, acting as an electrical shunt, require special stimulation parameters. Until now, no appropriate devices (stimulators) are commercially available. Therefore, we were forced to design our own stimulators. The control unit of the stimulators is based on a microprocessor for maximum flexibility regarding the generation of the parameters such as pulse amplitudes, pulse width, frequency, stimulation times, ramps, and so on. In addition, the microprocessor design allows recording of compliance data such as stimulation date, time, duration, and used programs. The constant voltage output stage of the stimulator is able to generate biphasic charge balanced stimulation impulses with a pulse width of 1 to 300 ms, voltage amplitudes up to +/-80 V (160 VPP), and stimulation currents up to 250 mA. To prevent direct current due to inexact charge compensation, the electrode outputs are decoupled capacitively. Simultaneous 2 channel stimulation with independent intensity levels is possible. The stimulators are programmed using a notebook or a personal digital assistant via infrared serial interface. This concept guarantees the application of correct stimulation parameters because the patient has only access to parameters that are preprogrammed for him in the outpatient clinic. For the home based training, access is limited to variation of intensity within preprogrammed limits. For safety reasons, the portable unit is powered by an internal rechargeable battery. High efficiency switched voltage regulators are used to provide the different required voltage levels while ensuring an acceptable operating time of the stimulator.