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R Graves

Publications and source records attributed to R Graves.

35 records · Page 2Linked to original sources
PubMed1985

On the interpretation of mouth asymmetry.

Greater right-side mouth opening during propositional speech has now been observed in at least eight studies. All current data are consistent with the interpretation that left-hemisphere control of articulation of propositional speech results in greater activity of the right-side lip opening muscles. In addition, expression of automatic speech such as singing, emotion, and possibly prosody can also influence mouth asymmetry, but in the opposite direction, suggesting a relatively greater right-hemisphere role for these types of expression. Further work is needed to confirm these interpretations and to elaborate on the exact neuro-muscular mechanisms and task dependencies responsible for mouth asymmetry.

Facial Expression↗
PubMed1985

Regulated expression of a chimeric histone gene introduced into mouse fibroblasts.

The regulated expression of a mouse histone gene was studied by DNA-mediated gene transfer. A chimeric H3 histone gene was constructed by fusing the 5' and 3' portions of two different mouse H3 histone genes. Transfection of the chimeric gene into mouse fibroblasts resulted in the production of chimeric mRNA at levels nearly equal to that of the total endogenous H3 histone mRNAs. Most chimeric RNA transcripts had correct 5' and 3' termini, and the chimeric mRNA was translated into an H3.1 protein that accumulated in the nucleus of the transfected cells. Expression of the chimeric gene was studied under several conditions in which the rate of transcription and the stability of endogenous H3 transcripts change. Chimeric mRNA levels were regulated in parallel with endogenous H3 mRNAs, suggesting that cis-acting regulatory sequences lie within or near individual histone genes. In addition to correctly initiated and terminated chimeric mRNA, we also detected a novel H3 transcript containing an additional 250 bases at the 3' end. Surprisingly, the longer transcript is polyadenylated and accumulates in the cytoplasm.

Animals↗
PubMed1983

Mouth asymmetry, dichotic ear advantage and tachistoscopic visual field advantage as measures of language lateralization.

Clinical evidence suggests that speech expression, speech comprehension and reading have distinct anatomical representations and that these functions may have differential degrees of lateralization. Experimental measures sensitive to the lateralization of these functions may be, respectively, mouth asymmetry, dichotic listening and visual field advantage. These measures, individually, showed relatively low success in estimating overall "language dominance" and had low intercorrelations. A composite measure was more successful. Language lateralization may not be unitary, and even if it is, a composite of several distinct measures may be necessary to index it.

Adolescent↗
PubMed1982

Mouth asymmetry during spontaneous speech.

A high proportion of normal subjects have speech expression controlled predominantly by the left hemisphere. Since the left hemisphere also has stronger control of the right side of the lower face, it might be expected that normal subjects would show a right-sided asymmetry in mouth opening during speech. This hypothesis was tested by measuring lip opening in 196 subjects. Of these, 150 (76%) showed greater right-side opening. This tendency was found for males, females, left- and right-handers in four experiments using two different techniques. Mouth asymmetry during speech may provide an indication of which hemisphere is dominant for expressive speech.

Adolescent↗
PubMed1982

Dissociation of ear preference in monaural word and voice recognition.

The ambiguity in the literature concerning cerebral dominance for voice recognition, has been investigated with a monaural go-no go task, using male and female voices. A left ear advantage for the male, and a right ear advantage for the female voice was found, suggesting that both hemispheres can perform voice recognition. A monaural word recognition test showed the expected left hemisphere dominance.

Adult↗
PubMed1982

Aphasic reading and writing: possible evidence for right hemisphere participation.

Aphasic patients performed two tasks, reading aloud and writing to dictation. In both tasks, success was positively correlated to the emotionality, the imageability and the frequency of the target words. In addition, the patients made more semantic Also, the relative difficulty of words was similar for aphasic patients to read and for normal male subjects to recognize in the left visual field. These results suggest that the performance of the aphasic patients on these language tasks were mediated in part by the right hemisphere.

Agraphia↗
PubMed1982

Visual recognition through kinaesthetic mediation.

A case is reported in which mercury intoxication produced visual symptoms with an unusual compensation. The similarity of this patient to Schn., a much reported neuropsychiatric case, was striking and prompted correlation of the two cases. Experimental psychological studies performed on the present case provide a basis for an understanding of both cases.

Adult↗
PubMed1981

Dissociated awareness of manual performance on two different visual associative tasks: a "split-brain" phenomenon in normal subjects?

Subjects performed two visual category matching tasks. One task, shown in previous work to exhibit a left hemisphere superiority, was to decide if two different pictures represented the same object. In this task, verbal corrections of manual responses were usually correct (93%), indicating good verbal awareness of the task. The other task, previously shown to exhibit a right hemisphere superiority, was to decide if two different pictures represented the same emotional facial expression. Here, verbal corrections were random (58%), indicating poor verbal awareness of the task. The apparent dissociation of verbal and manual responses for the emotional expression matching task resembles results obtained with "split brain" patients.

Adult↗
PubMed1980

[The role of the right hemisphere in reading (author's transl)].

Two tests were applied to demonstrate the specific role of the right hemisphere during reading of highly emotionally-charged words; recognition of words presented simultaneously to the tachistoscope in each visual half-field of normal subjects, and reading aloud by aphasic patients. The comparison of the results obtained in the two tests suggests that the right hemisphere plays a major functional role in aphasic subjects.

Aphasia↗
PubMed1978

A heavy particle comparative study. Part I: depth-dose distributions.

The results of a comparative study of heavy particles of interest in radiotherapy, with peaks spread over a depth of 10 cm, are reported in four parts. The introduction to this study and the depth-dose distributions of the particles, (n, pi-, p, He, C, Ne, and Ar ions) are reported herein. The results indicate that protons give the best localization of dose. The degree of localization of dose with heavy ions is reduced with increasing charge on the ion. For ranges less than 15cm, heavier ions such as neon and argon still have favourable dose localization; however, for ranges in excess of 15 cm, heavy ions such as argon are unfavourable but superior to fast neutrons because penetration can be controlled by modulation of energy or range.

Argon↗
PubMed1975

A basic aphasia examination: description with discussion of first results.

A new basic aphasia test (Grunntest for Afasi) constructed for use with a Norwegian patient population is briefly described. This test follows the principles established by Goodglass and Kaplan in the Boston Diagnostic Aphasia Examination. Results with the first 43 patients examined are presented. Three alternative methods for utilizing the basic results in classifying types of aphasic disorder are considered. The classical method, as formalized by Goodglass and Kaplan, which emphasizes an evaluation of patients' speech characteristics was found to employ dimensions with the lowest intercorrelations. While this method provided the better dimensions, the description of disorder in terms of classical syndromes defined by impairment along these dimensions could not classify a majority of the patients. However, the dimensions on which such classification is based (Fluency, Comprehension, Naming, Repetition) form a useable descriptive system.

Aphasia↗
PubMedDate not supplied

Effects of filters and wedges on skin sparing and gamma/neutron dose ratios in neutron teletherapy.

The effects of skin sparing and the gamma/neutron dose ratios in the clinical situations presently in use at the TAMVEC neutron teletherapy facility are not appreciably affected by the presence of filters and/or wedges. It is also shown that if skin sparing is lost due to close proximity of a hydrogenous scattering source, it can be restored by the use of thin lead filters.

Gamma Rays↗
PubMedDate not supplied

Calorimetric and ionimetric dosimetry intercomparisons I: U.S. neutron radiotherapy centers.

In the U.S. neutron radiotherapy trial centers, absorbed dose is routinely measured using commercially available A-150 tissue equivalent (TE) plastic ionization chambers. The collecting volumes of these chambers are filled with either methane-based tissue equivalent gas or air. Absorbed dose in A-150 plastic, determined with these ionization chambers, was compared to that measured by an A-150 plastic calorimeter in an A-150 plastic phantom. These comparisons have yielded the following information: (1) Agreement of the total absorbed dose measured using the ionization chambers was within 2.5% of the calorimeter at all the centers visited to date. (2) For all the neutron fields measured, the product of the stopping power ratio (sw,g)N' between the A-150 plastic chamber wall and TE gas, and the average energy expended in the gas per ion pair formed, WN/e, was computed assuming Bragg-Gray theory and found to be 31.0 +/- 0.7 J/C. (3) The displacement correction factor employed to normalize measurements at a depth in a phantom using the type IC-17 ionization chamber was verified to be approximately 0.97 +/- 0.01.

Calorimetry↗