Fractionating language: different neural subsystems with different sensitive periods.

Theoretical considerations and psycholinguistic studies have alternatively provided criticism and support for the proposal that semantic and grammatical functions are distinct subprocesses within the language domain. Neurobiological evidence concerning this hypothesis was sought by (1) comparing, in normal adults, event-related brain potentials (ERPs) elicited by words that provide primarily semantic information (open class) and grammatical information (closed class) and (2) comparing the effects of the altered early language experience of congenitally deaf subjects on ERPs to open and closed class words. In normal-hearing adults, the different word types elicited qualitatively different ERPs that were compatible with the hypothesized different roles of the word classes in language processing.

Familial inclusion body myositis: evidence for autosomal dominant inheritance.

We report a kindred manifesting clinical features and muscle biopsy findings of inclusion body myositis (IBM). In this family, multiple members were affected in two generations with direct male-to-male and female-to-male transmission. This is the first reported instance of autosomal dominant inheritance in IBM, which usually occurs sporadically or, rarely, may be transmitted as an autosomal recessive disorder.

Syntactically based sentence processing classes: evidence from event-related brain potentials.

Theoretical considerations and diverse empirical data from clinical, psycholinguistic, and developmental studies suggest that language comprehension processes are decomposable into separate subsystems, including distinct systems for semantic and grammatical processing. Here we report that event-related potentials (ERPs) to syntactically well-formed but semantically anomalous sentences produced a pattern of brain activity that is distinct in timing and distribution from the patterns elicited by syntactically deviant sentences, and further, that different types of syntactic deviance produced distinct ERP patterns. Forty right-handed young adults read sentences presented at 2 words/sec while ERPs were recorded from over several positions between and within the hemispheres.

Effects of locus coeruleus lesions on auditory, long-latency, event-related potentials in monkey.

It has previously been demonstrated that monkeys exhibit certain event-related potential (ERP) components showing latency, polarity, and contingency similarities to those observed in humans. In the present study, monkey P300-like components were studied in order to evaluate the hypothesis that the noradrenergic locus coeruleus (LC) system participates in their generation or modulation. ERPs were recorded from untrained squirrel monkeys (Saimiri sciureus) twice a week for 4 weeks before and after bilateral LC lesions and interruption of dorsal bundle (DB) fibers.

Endogenous event-related potentials in monkey: the role of task relevance, stimulus probability, and behavioral response.

Monkeys were trained in auditory discrimination tasks resembling human paradigms in which long-latency endogenous components, such as P300, are typically recorded. Morphological, topographical, and functional properties of the monkey event-related potentials (ERPs) were analyzed to determine similarities and differences with human ERPs reported in the literature. ERPs were recorded from epidural electrodes in monkeys trained to produce operant responses.

Isolated vitamin E deficiency in the absence of fat malabsorption--familial and sporadic cases: characterization and investigation of causes.

We observed four young adults, including three siblings, with a progressive neurologic disorder that developed over the first two decades. Electrophysiologic studies revealed mildly delayed nerve conduction, decreased amplitudes of sensory action potentials, and sensory delay in the posterior columns. Known causes of similar neurologic disorders were excluded.

Motor neuron disease in the Rocky Mountain region.

We saw 166 patients with motor neuron disease over a ten-year period, 116 with amyotrophic lateral sclerosis-111 sporadic and 5 familial-and 50 with progressive muscular atrophy. The age at onset varied widely, with the youngest mean onset occurring in the familial group. The most common presenting symptoms were leg or arm weakness and difficulty speaking or swallowing; fewer patients reported cramping, fasciculation, or fatigue.

Spectrum of inclusion body myositis.

The clinical, laboratory, and biopsy features are described for a large group of patients with inclusion body myositis (IBM) (15 men and four women; mean age, 63 years). A quantitative histopathologic analysis of muscle biopsy specimens revealed less fiber necrosis and endomysial and perivascular inflammation in IBM than in polymyositis (PM) and dermatomyositis, but a more frequent occurrence of dark-angular and hypertrophied fibers. Rimmed vacuoles were present in 3.

Lack of tocopherol in peripheral nerves of vitamin E-deficient patients with peripheral neuropathy.

Vitamin E deficiency is often associated with symptoms of a peripheral neuropathy. To evaluate whether vitamin E deficiency affects the vitamin E content of the peripheral nervous system, we measured the alpha-tocopherol content in biopsy specimens of sural nerve and adipose tissue from 5 patients with symptomatic vitamin E deficiency (2 with homozygous hypobetalipoproteinemia and 3 with familial isolated vitamin E deficiency) and 34 control patients with neurologic diseases without vitamin E deficiency. A significant reduction in tissue tocopherol content was present in the vitamin E-deficient patients, as compared with the controls, both in sural nerves (1.

Long-latency event-related potentials in squirrel monkeys: further characterization of wave form morphology, topography, and functional properties.

Event-related potentials (ERPs) were recorded from the brain surface of untrained monkeys exposed to sequences of auditory stimuli (2 kHz and 6 kHz tones of 40 msec duration). Stimulus probability and interstimulus interval (ISI) were systematically varied in different paradigms. In an oddball paradigm with a 1 sec ISI in which one stimulus constituted 90% of all trials and the other 10%, a 'monkey' late positive component (MLPC), characterized by two peaks (P248 and P369), was recorded prominently over lateral parietal areas in response to the unpredictable and infrequent shifts in pitch.

Attention to central and peripheral visual space in a movement detection task. III. Separate effects of auditory deprivation and acquisition of a visual language.

We employed event-related brain potentials (ERPs) and measures of signal detectability to compare attention to peripheral and central visual stimuli in normal hearing subjects who were born to deaf parents (HD Ss) and whose first language was American Sign Language (ASL). The results were compared with those obtained from normal hearing Ss and congenitally deaf Ss in the same paradigm. Task performance and ERPs during attention to the foveal region were similar in the 3 groups.

Attention to central and peripheral visual space in a movement detection task: an event-related potential and behavioral study. II. Congenitally deaf adults.

We compared the effects of focussed attention upon event-related brain potentials (ERPs) to peripherally and centrally located visual stimuli in congenitally deaf subjects (Ss). The results were compared with those obtained from a group of normal hearing Ss in the same paradigm. ERPs from deaf and hearing Ss displayed similar attention-related changes with attention to the centrally located stimuli.

Attention to central and peripheral visual space in a movement detection task: an event-related potential and behavioral study. I. Normal hearing adults.

The effects of focussed attention to peripherally and centrally located visual stimuli were compared via an analysis of event-related brain potentials (ERPs) while subjects detected the direction of motion of a white square in a specified location. While attention to both peripheral and foveal stimuli produced enhancements of the early ERP components, the distribution over the scalp of the attention-related changes varied according to stimulus location. The attention-related increase in the amplitude of the N1 wave (157 ms) to the peripheral stimuli was greater over the parietal region of the hemisphere contralateral to the attended visual field.

Friedreich's disease: V. Variant form with vitamin E deficiency and normal fat absorption.

A 30-year-old woman was thought to have Friedreich's disease because of progressive ataxia, dysarthria, and titubation from age 3 years. Her diet was normal, and there were neither symptoms nor laboratory evidence of liver disease or fat malabsorption. Serum vitamin E content and the ratio of serum vitamin E to total serum lipid were very low, but serum vitamin A, cholylglycine, and lipid levels were normal, as was an oral vitamin E tolerance test.

Tubular aggregates. Their association with neuromuscular diseases, including the syndrome of myalgias/cramps.

Tubular aggregates of muscle are distinctive structures seen in a wide variety of disorders. We reviewed 1,500 consecutive muscle biopsy specimens for the presence of tubular aggregates. Fifteen biopsy specimens (1.

Language processing in men at risk for alcoholism: an event-related potential study.

Event-related potentials (ERPs) were recorded from a group of men with (FH+) and without (FH-) a family history of alcoholism. ERPs were recorded over the left and right cerebral hemispheres and over midline locations while subjects performed a letter rhyming task. The ERPs to the letters displayed major group differences in a negative component with a latency of 430 msec (N430).

Protein degradation in cultured skeletal muscle from Duchenne muscular dystrophy patients.

The loss of contractile protein in Duchenne muscular dystrophy could result from low rates of synthesis, abnormally high rates of protein degradation, or a combination of both. We measured overall protein degradation rates in cultured human muscle cells obtained at biopsy from patients with Duchenne dystrophy or various muscle diseases and normal subjects. Measurements were performed on confluent cultures exhibiting no growth and containing a mixed cell population of myoblasts, fibroblasts, and multinucleated myotubes.

Treatment of refractory chronic demyelinating polyneuropathy with lymphoid irradiation.

Four patients with refractory or poorly responsive chronic progressive demyelinating polyneuropathy (CPDP) were treated with total lymphoid irradiation (total dose, 2000 rad) in an uncontrolled feasibility study. All patients had previously failed conventional therapy for CPDP, as well as other unconventional treatments. During a follow-up period of 7 to 12 months after total lymphoid irradiation, there was a profound and sustained suppression of the absolute lymphocyte count and in vitro lymphocyte function, as well as an increase in the ratio of Leu-2 (suppressor/cytotoxic subset) to Leu-3 (helper/inducer subset) T cells in the blood.

Naloxone increases electrophysiological measures of selective information processing in humans.

The effects of the opiate antagonist naloxone on electrophysiological measures of human selective attention were examined utilizing a paradigm which dissociates selective information processing from any concurrent processes of general arousal that may be present. Subjects were injected with naloxone (2 mg, i.v.

Auditory event-related potentials in the squirrel monkey: parallels to human late wave responses.

Event-related potentials (ERPs) were recorded from the brain surface in squirrel monkeys during the presentation of two auditory stimulus paradigms which have previously been utilized to elicit scalp-recorded ERPs in humans. In the first paradigm, inter-stimulus interval (ISI) was systematically varied during the presentation of a series of tone pips. The tones produced a negative (70 ms)-positive (130 ms) sequence of components similar in morphology to the human scalp-recorded N1-P2 'vertex' potential.

Bitemporal lesions dissociate auditory evoked potentials and perception.

We studied auditory evoked potentials (AEPs) in an 82-year-old female patient who became suddenly deaf following the second of two strokes. The patient showed markedly elevated pure tone thresholds, was unable to discriminate sounds and could not understand speech. Brain-stem auditory evoked potentials (BAEPs) were normal.