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R P Hemmingsen

Publications and source records attributed to R P Hemmingsen.

14 recordsLinked to original sources
PubMed2006

Structural brain abnormalities in early onset first-episode psychosis.

BACKGROUND: Brain morphometry in children and adolescents with first-episode psychosis offer a unique opportunity for pathogenetic investigations. METHODS: We compared high-resolution 3D T1-weighted magnetic resonance images of the brain in 29 patients (schizophrenia, schizotypal disorder, delusional disorder or other non-organic psychosis), aged 10-18 to those of 29 matched controls, using optimized voxel-based morphometry. RESULTS: Psychotic patients had frontal white matter abnormalities, but expected (regional) gray matter reductions were not observed. Post hoc analyses revealed that schizophrenia patients (n = 15) had significantly larger lateral ventricles as compared to controls. Duration and dose of antipsychotics correlated negatively with global gray matter volume in minimally medicated patients (n = 18). CONCLUSION: Findings of white matter changes and enlarged lateral ventricles already at illness onset in young schizophrenia spectrum patients, suggests aberrant neurodevelopmental processes in the pathogenesis of these disorders. Gray matter volume changes, however, appear not to be a key feature in early onset first-episode psychosis.

Adolescent↗
PubMed2001

A mixed modality paradigm for recording somatosensory and auditory P50 gating.

Significant somatosensory evoked potential (SEP) P50 gating has previously been found in young healthy men by the use of identical paired stimuli. In this study, the exploration of the gating paradigm was extended with the addition of a mixed modality paradigm where three different pairs of identical stimuli (clicks, right median nerve electric stimulations and proprioceptive stimuli of changing load on a handheld weight) were presented over a 12-s cycle. In both modalities repeated measures analyses of variance demonstrated no effect of paradigm. This mixed-modality recording paradigm could be used in further experiments to examine gating deficits across modalities.

Adult↗
PubMed2001

Gating of the vertex somatosensory and auditory evoked potential P50 and the correlation to skin conductance orienting response in healthy men.

A defect in auditory evoked potential (AEP) P50 gating supports the theory of information-processing deficits in schizophrenia. The relationship between gating of the mid-latency evoked potentials (EP) in the somatosensory and the auditory modalities has not been studied together before. In schizophrenia, we might expect the processing deficits to act on multiple modalities. We have examined the gating of median nerve somatosensory EP (SEP) following paired stimulation identical to the AEP P50 gating paradigm using interstimulus intervals (ISI) of 500, 750 and 1000 ms and the correlation of gating to the skin conductance orienting response (SCOR) in 20 healthy men. We measured mid-latency vertex components (SEP: P50, N65, P85 and N100; AEP: P30, N45, P50 and N80). The gating was most pronounced at ISI 500 ms where the SEP P50 and N100 gating were 0.59 and 0.37, respectively, as compared to a gating of 0.61 in P30, 0.33 in P50 and 0.45 in N80 in the AEP. Repetition effects in the two modalities were not correlated. AEP P50 gating was correlated to skin conductance level (SCL). The combination of recording repetition effects on the mid-latency EP in two modalities could provide a method for investigating if deficits of information processing in schizophrenia are cross-modal.

Adult↗
PubMed1999

[Transmitter dysfunction in patients with schizophrenia. Significance for cognitive functioning and treatment].

The great diversity of schizophrenic symptoms rules out one simple etiological explanation. However,impairment of information processing, including disruption of sensorimotor gating, is a consistent finding in schizophrenic patients. Dysfunction in sensorimotor gating is believed to be the result of different developmentally or environmentally caused disturbances involving the neural trajectories involved in information processing. Psychopathology and cognition will depend on the primary involvement of distinct parts of these circuits and on secondarily derived time-dependent disturbances of transmitter function. This review is focused on clinical and preclinical evidence for the impact of interactions between glutamatergic, dopaminergic, serotonergic and noradrenergic brain systems on cognitive performance. The hypothetical consequences of transmitter dysfunction for progressive development of impairment in sensorimotor gating are illustrated. Finally, the broad receptor profile of second generation antipsychotics is analysed to explain the clinical improvement in neurocognition that may occur during treatment with such drugs.

Antipsychotic Agents↗
PubMed1997

[Intrauterine growth retardation and premature delivery. The effect of smoking and psychosocial factors].

The purpose of the study is to investigate the influence of psychosocial stress, maternal schooling, social support, psychological well-being, alcohol and smoking on intrauterine growth retardation and premature delivery. At a Copenhagen university hospital 2432 consecutive Danish-speaking women in 20th week of pregnancy completed a questionnaire including the General Health Questionnaire and Severity of Psychosocial Stressor Scale and questions about social network, education, smoking and drinking habits. In 212 cases (8.7%) the women delivered before day 259 of gestation. In a multiple logistic regression model, pre-term delivery proved to be associated with psychosocial stress and poor school education. In 152 cases (6.3%) infants had a birth weight below the defined 10th percentile. In a multiple logistic regression model, IUGR was associated with smoking. In preventive programmes, such as anti-smoking campaigns, it should be kept in mind that women who smoke are also the least educated and have the poorest support from a social network.

Adult↗
PubMed1997

[Group homes for the mentally ill I. A description of access and residents].

In a cross-sectional study, we assessed social and psychiatric characteristics of 71 residents in the group home programme for the mentally ill in Copenhagen. The majority suffered from long-term functional or organic psychosis, dominated by anxiety and residual symptoms of schizophrenia. Social functioning was impaired to a moderate degree. Emotional and social support were among the main functions of the staff. More than 60% regarded the group home as a temporary residence, but the length of stay varied between a few months and 5.7 years. All residents were treated in the local outpatient psychiatric service. This type of housing support should be regarded as an important part of a comprehensive community care service.

Adult↗
PubMed1996

[The significance of psychosocial stress for pregnancy course and fetal development].

In a population-based study, 3021 women in a central Copenhagen district received a questionnaire on environmental and psychological factors during mid-gestation. Of these, 70 women were selected consecutively on the basis of moderate to severe stressful life-events (DSM-III-R categories 3 to 5), in combination with an inadequate social network. They were compared with 50 non-stressed women with an intact social network. Stress and smoking significantly affected birthweight and head circumference. When birthweight was corrected, stress remained a significant determinant of small head circumference, indicating a specific effect on brain development. Stress also led to a suboptimal Prechtl neonatal neurological score. These findings suggest the existence of a fetal stress syndrome with adverse effects on fetal development, including deficient brain development.

Birth Weight↗
PubMed1996

[Abnormal neurological findings at first admission in patients with schizophrenia or schizophreniform disorders. Results of computer tomography and measurement of regional cerebral blood flow].

Forty-five patients with schizophrenia or schizophreniform disorder admitted to hospital for the first time had a neurological examination, including integrative sensory and complex motor acts, by a trained neurologist. The patients were studied by CT and regional cerebral blood flow as well. A control group of 24 healthy volunteers was included. The patients had significantly more neurological abnormalities (NA) than the healthy volunteers. Medication did not explain the discrepancy. The NA were associated with sulcal enlargement and smaller brains as visualized by CT but not with ventricular enlargement. There was no association between the regional flow values and NA.

Adolescent↗
PubMed1993

[Structural and functional cerebral changes in patients with schizophrenia].

During the past decades the possibility of measuring regional brain structure and function by computed tomography, magnetic resonance, single photon emission computed tomography and positron emission tomography has brought the biological research on schizophrenia into focus. Structural changes with enlargement of the lateral and third ventricle and broader sulci on the brain surface compared to those of healthy volunteers have been reproducible findings. Functionally, the reduced activity in the prefrontal cortex especially during activation tests has been the most reliable finding. However, the etiology and specific meaning of the brain changes remains unsolved. Furthermore, in all the studies performed there is a considerable overlap in the measurements in the schizophrenic patients and in the controls.

Brain↗
PubMedDate not supplied

Apolipoprotein D is associated with long-term outcome in patients with schizophrenia.

Accumulating evidence implicates deficiencies in apolipoprotein D (ApoD) function and arachidonic acid signaling in schizophrenic disorders. We addressed two hypotheses in relation to ApoD: first, polymorphisms in the ApoD gene confer susceptibility to or are markers of disease, and, second, genetic variation in the ApoD is associated with long-term clinical outcome to antipsychotic treatment. We genotyped two single-nucleotide polymorphisms in the ApoD gene in 343 chronic patients with schizophrenia spectrum disorders (ICD-10) and 346 control subjects of Danish origin. We did not find ApoD alleles, genotypes or haplotypes to be associated with disease. However, we did find that long-term clinical outcome was associated with the ApoD polymorphism rs7659 (P = 0.041) following adjustment for lifetime clinical global impression, age at first admission and gender.

Adult↗