R Henchey | PubMed Health

PubMed1995

Electroencephalographic findings in Hashimoto's encephalopathy.

Hashimoto's encephalopathy (HE) is a steroid-responsive relapsing disorder that frequently presents with seizures and diffuse EEG abnormalities. We report the EEG findings in seven patients with encephalopathy, seizures, or both, associated with elevated antithyroid antibodies. There were several combinations of findings within the same patient and between patients. The EEGs of five patients had generalized slowing or frontal rhythmic slowing; two also had triphasic waves and one had periodic sharp waves. Three had focal left temporal slowing. HE is heterogeneous clinically and electrographically. A high level of suspicion is necessary to establish the diagnosis.

Adult↗

PubMed1995

Apraxia during Wada testing.

Apraxia is the loss of the ability to perform learned skilled movements correctly. In right-handers, apraxia and aphasia are most frequently associated with left-hemisphere lesions. When they are dissociated, however, aphasia is more common in the absence of apraxia than vice versa. There are two hypotheses that can account for this discrepancy: (1) in right-handers, praxis is more likely than language to be mediated by the right hemisphere, or (2) the left-hemisphere network that mediates language is either more widely distributed than the network that mediates praxis or is more likely to be in the middle cerebral artery distribution. We studied apraxia in a group of right-handers undergoing selective hemispheric anesthesia, or Wada testing. All nine subjects had language lateralized to the left hemisphere, and seven of the nine had praxis lateralized to the left hemisphere. Two of the subjects had praxis bilaterally represented. Although our data suggest that speech and praxis functions tend to be lateralized to the left hemisphere in most right-handers, praxis appears to be more distributed between the hemispheres than speech-language functions. Furthermore, an analysis of the types of errors made during praxis testing suggests differential roles of the hemispheres in praxis functions.

Adolescent↗