Biomedical subjects

R Kennison

Publications and source records attributed to R Kennison.

9 recordsLinked to original sources

PubMed1996

One-trial associative priming of nonwords in young and older adults.

In this article, three experiments in which single-trial associative priming for nonwords was investigated in young and older adults in a pronunciation task are reported. During an encoding task, associative priming was observed for young and older adults, although cued recall was near zero for both groups. Associative priming for young and older adults was found under full attention conditions, but when attention was divided at study, associative priming was observed in Experiment 3, but not in Experiment 2. Divided attention also disrupted recognition memory for new associations in young and older adults. The results limit the generality of findings of age-related decrements in associative priming by showing an absence of such decrements in tasks that do not require elaborative processing during encoding. They also argue against G. Musen and L. Squire's (1993) suggestion that formation of new connections in implicit memory requires multiple study opportunities, whereas declarative memory is specialized for rapid acquisition of new associations.

Adult↗

PubMed1995

Repetition priming of nonwords in young and older adults.

In 3 experiments, a pronunciation task was used to examine repetition priming of novel nonwords in young and older adults. The contributions of item and associative priming to the total repetition priming effect were assessed. In Experiment 1, age consistency was found in both components of repetition priming after 9 repetitions of nonwords. Experiment 2 established that young and older adults were similar in item and associative priming after as few as 2 repetitions of nonwords. Finally, Experiment 3 demonstrated that associative priming persists for at least 3 min and that it is dissociable from cued recall. The overall pattern of results strongly argues that elaborative processing is not necessary to obtain associative priming in indirect memory tasks and that young and older adults show similar magnitudes of associative priming.

Adolescent↗

PubMed1991

A rapid visual test for predicting fetal lung maturity.

A rapid bedside test has been devised that enables an untrained observer to predict (p less than 0.001) when amniotic fluid will be greater than or equal to 0.15 at an optical density of 650 nm, lecithin/sphingomyelin ratio will be greater than or equal to 2.0, or when phosphatidylglycerol will be present. By a visual comparison of the turbidity of unspun amniotic fluid against positive (mature) or negative (immature) controls, technicians and resident physicians who had had no special training were able to classify correctly 87.2% (82/94) of unknown amniotic fluid samples. The sensitivity of the new test is 90.8% (58/65); the specificity is 70.3% (23/29). Thus, when more sophisticated methods are not readily available, we believe that this easily performed and accurate test can provide supplemental or preliminary data for patient management. In remote geographic areas our method could serve as the primary source of information about fetal lung maturity.

Amniotic Fluid↗

PubMed1989

Asymmetry in the relationship between finger temperature changes and emotional state in males.

Eighty male college students each listened to monaural music that was intended to cause either positive-valence emotions (e.g., happiness) or negative-valence emotions (e.g., unhappiness). When the music was to the left ear, subjects' finger temperature changes during the music correlated significantly with the subjects' ratings of the valence of the emotions they experienced during the music. When the music was to the right ear, finger temperature changes were not different during positive- versus during negative-valence music, and the subjective reports did not correlate significantly with the finger temperature changes. The results are interpreted as indicating that the extent to which males' autonomic responses, such as finger temperature changes, reflect the emotional state of the subject depends upon which cerebral hemisphere is more involved in the processing of the emotion-generating stimulus. Theoretical and practical aspects of this finding are discussed.

Adult↗

PubMed1989

Handedness affects emotional valence asymmetry.

Music was played monaurally to 80 right-handed and 80 left-handed subjects. Right-handers reported more positive and less negative effect if the music was to the right ear. Left-handers reported experiencing more positive and less negative effect during music to the left ear. The hand x ear interaction was significant. The valence of emotional responses to the music seems influenced by a combination of at least two factors, (1) differences between left- and right-handers in the cerebral processing of emotional valence and (2) differences in the processing of emotional valence within each handedness group depending upon which hemisphere was initially most strongly engaged by the music. These results partially corroborate and extend stimuli were presented tachistoscopically or dichotically. It is concluded that, while there is hemispheric asymmetry in the processing of emotional valence, the direction of the asymmetry may be associated with the handedness of the subjects.

Acoustic Stimulation↗

PubMed1985

Cesarean delivery and severe idiopathic thrombocytopenic purpura. A case report.

A postsplenectomy patient had idiopathic thrombocytopenic purpura (ITP) that was exacerbated with both her pregnancies. She failed to have sustained platelet counts in her previous pregnancy in spite of receiving steroids and chemotherapy. She underwent elective cesarean section with a platelet count of 7,000 but did not receive platelet transfusions. No unusual bleeding occurred, and an improvement in the ITP was noted postpartum.

Adult↗

PubMed1984

Correlation of amniotic fluid optical density at 650 nm and lecithin/sphingomyelin ratios with phosphatidylglycerol.

In this study we have attempted to correlate amniotic fluid optical density measurements and lecithin/sphingomyelin (L/S) ratios with the presence of phosphatidylglycerol. An 85% correlation (126 of 148) of all three parameters was noted. When the assumption was made that phosphatidylglycerol is indicative of fetal pulmonary maturity, 93 of 94 fluid samples having an optical density at 650 nm greater than or equal to 0.15 had demonstrable phosphatidylglycerol for a 1% false positive rate. In 53 fluid samples having an optical density at 650 nm less than 0.15, phosphatidylglycerol was present in 11 and absent in 42, a 21% false negative rate. The same analyses with lecithin/sphingomyelin ratios showed a 5% false positive rate and a 31% false negative rate.

Amniotic Fluid↗

PubMed1983

Phagocytosis and onset of human labor.

An in vitro experimental model has been developed which allows the study of amnion lysosomal enzyme release under controlled conditions. Briefly, a layer of human amnion membrane mounted on a specially designed reaction vessel serves as the reaction surface. We have noted that the addition of particulate material to these membranes incubating in pseudoamniotic fluid results in an increased release of the lysosomal marker enzyme N-acetylglucosaminidase when compared to the release in the absence of particles. This release is completely inhibited by iodoacetate and slightly by azide. A similar increased release is also noted with the use of term amniotic fluid as incubation medium when compared to centrifuged (30,000 g/20 min) amniotic fluid. Lecithin and lysolecithin were effective in releasing increasing amounts of enzyme. This increased release was noted only from membranes of placentas collected from subjects who had undergone cesarean section prior to labor. Membranes collected from vaginal deliveries after labor showed a baseline increased release but no further stimulation upon the addition of any of the substances. These results suggest that the release of lysosomal enzymes from amnion membranes is brought about by substance(s) present in amniotic fluid. Very probably, these are surfactants. The interaction of these substances with amnion cells would eventually result in an exponential burst of prostaglandin synthesis, which would result in labor.

Acetylglucosaminidase↗

PubMed1981

Triplet pregnancies.

Fifteen triplet gestations delivered over 23 years beginning with 1954 are reviewed. The mortality rate was 7.1% in the gestation period of 28 weeks or more. This mortality rate compares favorably with the 15% to 50% rate reported in the literature. Among the third babies of each set, there was a mortality rate of 14.3%, again confirming the high mortality rate reported in the literature. Morbidity in triplet gestations was equally elevated. Although the data do not suggest what the best method of delivery is, the increased morbidity and mortality for the third baby of the set delivered vaginally implies that a more liberal use of cesarean section may reduce the potential risks for that baby. Also, among the eight cesarean sections performed in pregnancies at 28 weeks of gestation or more that have been reported in the literature, none of the babies died during the neonatal period.

Apgar Score↗