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Göran Hajak

Publications and source records attributed to Göran Hajak.

At least 19 recordsLinked to original sources
PubMed2006

Transcranial magnetic stimulation for the treatment of tinnitus: a new coil positioning method and first results.

Auditory phantom perceptions are associated with hyperactivity of the central auditory system. Neuronavigation guided repetitive transcranial magnetic stimulation (rTMS) of the area of increased activity was demonstrated to reduce tinnitus perception. The study aimed at developing an easy applicable standard procedure for transcranial magnetic stimulation of the primary auditory cortex and to investigate this coil positioning strategy for the treatment of chronic tinnitus in clinical practice. The left gyrus of Heschl was targeted in 25 healthy subjects using a frameless stereotactical system. Based on individual scalp coordinates of the coil, a positioning strategy with reference to the 10--20-EEG system was developed. Using this coil positioning approach we started an open treatment trial. 28 patients with chronic tinnitus received 10 sessions of rTMS (intensity 110% of motor threshold, 1 Hz, 2000 Stimuli/day). Being within a range of about 20 mm diameter, the scalp coordinates for stimulating the primary auditory cortex allowed to determine a standard procedure for coil positioning. Clinical validation of this coil positioning method resulted in a significant improvement of tinnitus complaints (p<0.001). The newly developed coil positioning strategy may have the potential to offer a more easy-to-use stimulation approach for treating chronic tinnitus as compared with highly sophisticated, imaging guided treatment methods.

Adult↗
PubMed2006

Panic disorder during pregnancy and postpartum period.

BACKGROUND: Earlier studies on the influence of pregnancy and postpartum period on the course of panic disorder have been inconsistent. The present study aims to quantify panic manifestations in these periods in large sample of women. METHOD: Panic manifestations, including exacerbations and new manifestations of panic disorder, were assessed retrospectively in a sample of 128 women with panic disorder with or without agoraphobia, 93 of whom had had 195 pregnancies. RESULTS: Panic manifestations were fewer during pregnancy and more frequent in the postpartum period when compared with the control period. Women who had never been pregnant had significantly more panic manifestations than women with prior pregnancies. Breastfeeding and miscarriages did not have a significant effect. Women with postpartum panic reported more psychosocial stress events during this period. CONCLUSIONS: Possible reasons for postpartum panic and the protective effects of pregnancy are discussed, including psychosocial or hormonal factors and other neurobiological changes. Postpartum panic coincides with a sudden drop of hormones after delivery.

Adult↗
PubMed2006

Integration of emotion and cognition in patients with psychopathy.

Psychopathy is a personality disorder associated with emotional characteristics like impulsivity, manipulativeness, affective shallowness, and absence of remorse or empathy. The impaired emotional responsiveness is considered to be the hallmark of the disorder. There are two theories that attempt to explain the emotional dysfunction and the poor socialization in psychopathy: (1) the low-fear model and (2) the inhibition of violence model. Both approaches are supported by several studies. Studies using aversive conditioning or the startle modulation underline the severe difficulties in processing negative stimuli in psychopaths. Studies that explore the processing of emotional expressions show a deficit of psychopathic individuals for processing sad or fearful facial expressions or vocal affect. In the cognitive domain, psychopaths show performance deficits in the interpretation of the motivational significance of stimuli. Studies investigating the impact of emotions on cognitive processes show that in psychopaths in contrast to healthy controls negative emotions drain no resources from a cognitive task. It is suggested that dysfunctions in the frontal cortex, especially the orbitofrontal cortex, the cingulate cortex and the amygdala are associated with the emotional and cognitive impairments.

Antisocial Personality Disorder↗
PubMed2006

The impact of auditory cortex activity on characterizing and treating patients with chronic tinnitus--first results from a PET study.

CONCLUSION: Unilaterally increased metabolic activity within the primary auditory cortex (PAC) represents a robust finding in tinnitus patients. Targeting these hyperactive areas with image-guided low frequency repetitive transcranial magnetic stimulation (rTMS) results in subjective tinnitus reduction. More pronounced activation of the PAC predicted higher resistance to rTMS. OBJECTIVES: [18F]deoxyglucose (FDG)-positron emission tomography (PET) was used to assess metabolic activity within the central auditory system in tinnitus. The study investigated whether patterns of neuronal activity correlate with clinical features or may be used for the prediction of treatment outcome. PATIENTS AND METHODS: Twenty patients with chronic tinnitus underwent PET imaging followed by low frequency rTMS treatment. Neuroimaging data were compared with clinical parameters and treatment outcome. RESULTS: PET data demonstrated an asymmetric activation of the central auditory system. Seventeen patients revealed increased activity of the primary auditory cortex on the left side, three on the right side. The extent of hypermetabolic activity prior to treatment correlated significantly with tinnitus reduction after rTMS, but not with clinical characteristics such as tinnitus severity, tinnitus laterality or tinnitus duration.

Adult↗
PubMed2006

Repetitive transcranial magnetic stimulation and chronic tinnitus.

CONCLUSION: There is a good theoretical basis and early research evidence suggesting that transcranial magnetic stimulation (TMS) may have treatment potential in tinnitus. Further studies with larger sample sizes and additional assessment of neurobiological effects are necessary. OBJECTIVES: Tinnitus is a common and often severely disabling disorder for which there is no satisfactory treatment. TMS is a new, non-invasive method of modifying the excitability of the cerebral cortex, which has proven effective in auditory hallucinations and other disorders. Some early studies have been published in which TMS has been used in the treatment of tinnitus. The objective of this paper is to examine the literature and consider the potential for TMS as a therapy in tinnitus. METHODS: A thorough search of the tinnitus and TMS literature was conducted, and all available relevant material was examined. RESULTS: Tinnitus is common, with a prevalence of 8.2% in subjects aged 50 years and over, and may be associated with great distress (tinnitus sufferers). There are no effective treatments. Tinnitus is frequently associated with deafness, and may be the result of a pathological plasticity process. Neuroimaging studies demonstrate increased activity within the central auditory system. TMS is a non-invasive method of modulating excitability in cerebral cortex. It uses electromagnetic principles and has been successfully employed in the treatment of other conditions associated with increased activity of the cerebral cortex. Meanwhile, a growing number of studies suggest that repetitive TMS may be effective in the treatment of chronic tinnitus.

Auditory Cortex↗
PubMed2006

The influence of age and sex on sleep latency in the MSLT-30--a normative study.

STUDY OBJECTIVES: The Multiple Sleep Latency Test-30 (MSLT-30) is a variation of the Multiple Sleep Latency Test with a fixed duration of 30 minutes for each of 5 test sessions. It requires less effort for reliable recording and is not susceptible to on-line scoring errors. The aim of the study was to provide normative data for the clinical use of the MSLT-30 and to evaluate the influence of age, sex, and other sociodemographic variables. DESIGN: An MSLT-30, along with measures of mood, objective, and subjective sleepiness was performed in a sample of healthy subjects in a balanced quota design. SETTING: Sleep laboratory in a sleep disorders center. PARTICIPANTS: One hundred subjects with no complaint of sleep disturbance or daytime sleepiness, 10 men and 10 women each from 5 age decades from 20 to 69 years. INTERVENTIONS: None. RESULTS: Mean latency to sleep stage 1 or any other sleep stage was 13.9 +/- 6.9 minutes. The SL-30 showed a clear quadratic association with age, with the shortest latencies in the middle age groups. No correlation was found between the mean latency to sleep stage 1 or any other sleep stage and sociodemographic variables or other measures of daytime sleepiness (Epworth Sleepiness Scale, vigilance test), mood scales, sleep quality (Pittsburgh Sleep Quality Index), and amount of prior sleep. CONCLUSIONS: Sleep latencies in normal subjects are age dependent in a quadratic fashion, with a minimum in middle-aged subjects. This reconciles the findings of a long mean sleep latency in the MSLT of adolescents and of an increase on the mean sleep latency with age in adults.

Adult↗
PubMed2006

Cerebellar and thalamic metabolic changes visualized by [18]-FDG-PET in olanzapine-induced acute akathisia.

OBJECTIVES: Akathisia is a clinical important symptom, frequently induced by neuroleptic treatment. Despite its clinical importance, less is known about its pathophysiology. METHODS: Using [18]-FDG-PET, imaging patterns of cortical metabolic activity were obtained in a patient during olanzapine-induced akathisia and after recovery. RESULTS: Akathisia was characterized by a reduced metabolic activity in thalamus and cerebellum. After discontinuing medication akathisia disappeared, reflected by a recovery of metabolic activity in these brain areas. CONCLUSION: [18]-FDG-PET may be useful to identify cortical regions mediating clinical aspects of drug-induced akathisia, thereby offering a deeper insight into the pathophysiology of this serious side effect.

Acute Disease↗
PubMed2005

Early traumatic life events, parental attitudes, family history, and birth risk factors in patients with borderline personality disorder and healthy controls.

Patients with borderline personality disorder (BPD) were compared with a healthy control group with regard to traumatic life events during childhood. The patients (n=66) and controls (n=109) were investigated using a comprehensive retrospective interview with 203 questions about childhood traumatic life events, parental attitudes, family history of psychiatric disorders and birth risk factors. The frequency of reports of traumatic childhood experiences was significantly higher in patients than in controls, including sexual abuse, violence, separation from parents, childhood illness, and other factors. On a 0- to 10-point "severe trauma scale," patients had significantly more severe traumatic events (mean score=3.86, SD=1.77) than control subjects (0.61, SD=0.93). Only four (6.1%) of the BPD patients, but 67 (61.5%) of the controls did not report any severe traumatic events at all. Compared with controls, patients described the attitude of their parents as significantly more unfavorable in all aspects. Patients reported significantly higher rates of psychiatric disorders in their families in general, especially anxiety disorders, depression, and suicidality. Among birth risk factors, premature birth was reported more often in BPD subjects. In a logistic regression model of all possible etiological factors examined, the following factors showed a significant influence: familial neurotic spectrum disorders, childhood sexual abuse, separation from parents and unfavorable parental rearing styles. The present data support the hypothesis that the etiology of BPD is multifactorial and that familial psychiatric disorders and sexual abuse are contributing factors.

Adolescent↗
PubMed2005

Altered motor cortex excitability in tinnitus patients: a hint at crossmodal plasticity.

Idiopathic tinnitus is a frequent and often debilitating auditory phantom perception of largely unknown pathological conditions. In electrophysiological and functional neuroimaging studies, affected subjects have shown excessive spontaneous activity in the central auditory system. To further investigate the underlying central nervous component, we assessed motor cortex excitability in 19 patients with chronic tinnitus by means of transcranial magnetic stimulation (TMS). When results were compared with data from 19 healthy controls matched for age and sex, we found significantly enhanced intracortical facilitation in tinnitus patients. These findings parallel excitability changes after limb amputation and experimental deafferentation. Our results give further support to crossmodal interactions involving neuroplastic changes in some forms of tinnitus and may help to better understand mechanisms of maladaptive cortical reorganisation involved in phantom perceptions.

Adult↗
PubMed2005

[The neuronal level of motor activity: determination of motor cortex excitability by TMS].

Transcranial magnetic stimulation as mapping method offers the possibility to measure aspects of motor cortex excitability painlessly and non-invasively. Using this neurophysiological tool, new insights into the effects of central-acting drugs are possible. Particularly striking seems to be the potential of this approach to gain new insights into neurobiological processes associated with neuropsychiatric diseases like schizophrenia or major depression. In combination with genetic aspects, TMS is able to bridge the gap between molecular research and clinical approach.

Antipsychotic Agents↗
PubMed2005

[Functional magnetic resonance tomography of central motor areas in schizophrenic patients].

Functional Magnetic Resonance Tomography (FMRT) is a safe and noninvasive method to study human brain function by measuring task induced changes of the regional cerebral blood flow. Recent fMRT studies showed that stimulation method, psychiatric disorders and neuroleptic agents influence motor induced brain activation patterns specifically. Since these factors have been insufficiently controlled in most of the recent fMRT studies in particular on psychiatric disorders, results are often controversial. Using an intrapersonal study design and a standardized stimulation apparatus, we explored differential effects of typical and atypical neuroleptic treatment in schizophrenia. In addition to fMRT, 3D ultrasonic assisted motor analysis was used to investigate gait and hand movements. FMRT method, fMRT studies on human motor system, fMRT data on schizophrenia as well as on the influence of neuroleptic treatment are given. In particular, the own study design is presented and preliminary data are given.

Amisulpride↗
PubMed2005

Gait disturbances in patients with schizophrenia and adaptation to treadmill walking.

This study evaluated the gait patterns of schizophrenic patients at free gait and at three fixed velocities on a treadmill. The effects of illness and antipsychotic treatment on gait parameters and on adaptation to treadmill walking were compared. Gait parameters of 14 drug-naive schizophrenic patients, 14 patients treated with conventional antipsychotics, 14 patients treated with olanzapine, as well as 14 matched controls were assessed on a walkway and on a treadmill at three different velocities (very slow, intermediately slow, and comfortable) using an ultrasonic movement analysis system. At free gait, all patients showed a significantly decreased gait velocity, predominantly due to a shorter stride length, when compared to the controls, with the most striking difference observed between the patients treated with conventional neuroleptics and the controls (ANOVA, P < or = 0.001). Cadence (steps per second) did not differ between the investigated groups. When gait was evaluated on the treadmill, differences in stride length and cadence were significant only at the very slow treadmill velocity (ANOVA, P < or = 0.05). In all patient groups, mean stride length was decreased and cadence compensationally increased. Significant differences between the patient groups were no longer detectable. With increasing treadmill velocities, gait parameters of all patient groups normalized. The results show that, like in patients with Parkinson's Disease, impaired gait parameters can also be normalized in schizophrenic patients by external stimulation via treadmill walking.

Adaptation, Physiological↗
PubMed2005

Oxidative stress during treatment with first- and second-generation antipsychotics.

Neurotoxicity of first-generation antipsychotics (FGAs) may be involved in lipid peroxidation, which is the pathogenesis of extrapyramidal symptoms, including tardive dyskinesia (TD). Blood samples at day 0, 7, and 21 drawn from patients taking antipsychotics were analyzed for malondialdehyde (MDA) in plasma, a marker of lipid peroxidation, by high-performance liquid chromatography. Of 115 patients enrolled, 92 patients completed the study. Most MDA levels were within normal ranges (<1.0 micromol/liter). Malondialdehyde levels in patients receiving clozapine (p = 0.002), quetiapine (p = 0.003), amisulpride (p = 0.008), and risperidone (p = 0.008) were significantly lower than within the first generation antipsychotic group. The authors conclude that lipid peroxidation is significantly higher in treatment with FGAs.

Adolescent↗