PubMed Health⌕ Search

Biomedical subjects

J Posthuma

Publications and source records attributed to J Posthuma.

7 recordsLinked to original sources
PubMed1990

Reliability, validity and follow-up of the EEG in senile dementia: sequelae of sequential measurement.

In a longitudinal study, slowing of the EEG in SDAT patients and elderly controls is investigated using both visual and power spectral analyses. For this a reliability study in 20 SDAT patients is performed and results for intra-rater, inter-rater and test-retest reliability (in 24 h) are used in the selection of parameters. Next, the diagnostic efficacy of the chosen parameters for SDAT is confirmed in a validity study in 43 SDAT patients, 41 elderly non-organic psychiatric patients and 51 elderly normals. In the longitudinal study 78 of these subjects could be retested after 20 months. The parameter for visual analysis appeared to be superior in actually showing a progress of slowing of the EEG in 20/21 SDAT patients over time. The parameter for power spectral analysis was superior in measuring the more subtle processes in the normal elderly. Results of these studies are used to discuss some problems in the measurement of EEG in SDAT over time.

Aged↗
PubMed1987

The influence of attention on visual evoked potentials in normal adults and dementias.

In normal subjects (n = 58, 22-71 y) the influence of the attention level on the VEP latency is studied, as is done in an additional small group of dementias (n = 14). The motor reaction time test (MRT) was selected to measure the attention level. The MRT was administered simultaneously with the VEP (checkerboard pattern reversal). By comparing VEP in test and non-test situations it proved that administration of MRT during VEP examination does not influence the VEP latencies. In dementias the motor reaction time is delayed but the degree of MRT delay did not correlate with the VEP latencies. This holds true for healthy volunteers as well as for demented patients. It is thus concluded that the latency increase of the late peaks of the VEP in dementias cannot be attributed to attentional deficits.

Adult↗
PubMed1985

Somatosensory evoked potentials in healthy volunteers and in patients with dementia.

In 56 healthy volunteers short, middle and long latency somatosensory evoked potentials were recorded bilaterally. The median nerve was electrically stimulated at the wrist. The impact of arm length and age on the peak latencies of the identified SEP components was investigated. Arm length relates to shoulder and neck SEP and to the N20, the primary cortical response. Age relates to all components of the SEP. A pilot study was performed in a small number of patients with senile dementia. A significant delay of the middle and long latency potentials compared to healthy volunteers was shown.

Adult↗
PubMed1983

Peripheral nerve conduction, visual evoked potentials and vitamin B1 serum level in chronic alcoholics.

70 chronic alcoholics were tested. In all patients VEP (pattern reversal) and MMCV (of the peroneal nerve) was examined. Moreover 47 of the patients underwent Hoffman reflex testing as well. In 16 (23%) of the patients the VEP P100 latency was delayed, in 21 (30%) the MMCV was decreased and in 16 (34%) the H-M interval was increased. A positive correlation was found between VEP latency and peroneal MMCV. VEP P100 delay is possibly caused by a subclinical optic neuropathy.

Alcoholism↗