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S Reilly

Publications and source records attributed to S Reilly.

At least 55 records · Page 3Linked to original sources
PubMed1996

Signaled Delay of Reinforcement: Effects of Postconditioning Manipulation of Context Associative Strength on Instrumental Performance

Two experiments examined the influence of postconditioning treatments of contextual cues on instrumental responding acquired with a signaled delay of reinforcement schedule. In Experiment 1, mere exposure to the conditioning context after instrumental training resulted in an attenuated response rate during an extinction test. In the second experiment, responding was decreased by exposure to the contextual cues or sessions in which signaled noncontingent reinforcements occurred. The greatest response decrement, however, occurred following unsignaled noncontingent food presentations. The results are discussed with respect to the different roles of contextual cues on operant responding.

Journal Article↗
PubMed1996

Prevalence of feeding problems and oral motor dysfunction in children with cerebral palsy: a community survey.

OBJECTIVE: To determine the prevalence and nature of feeding difficulties and oral motor dysfunction among a representative sample of 49 children with cerebral palsy (12 to 72 months of age). STUDY DESIGN: A population survey was undertaken by means of a combination of interview and home observational measures. RESULTS: Sucking (57%) and swallowing (38%) problems in the first 12 months of life were common, and 80% had been fed nonorally on at least one occasion. More than 90% had clinically significant oral motor dysfunction. One in three (36.2%) was severely impaired and therefore at high risk of chronic undernourishment. There was a substantial discrepancy between the lengthy duration of mealtimes reported by mothers and those actually observed in the home (mean, 19 minutes 21 seconds; range, 5 minutes 21 seconds to 41 minutes 39 seconds). In 60% of the children, severe feeding problems preceded the diagnosis of cerebral palsy. CONCLUSIONS: Using a standardized assessment of oral motor function, we found the majority of children to have clinically significant oral motor dysfunction. Contrary to maternal report, mealtimes were relatively brief, and this, combined with the severity of oral motor dysfunction, made it difficult for some children to achieve a satisfactory nutritional intake. The study illustrates the importance of observing feeding, preferably in the home.

Cerebral Palsy↗
PubMed1996

Gustatory thalamus lesions in the rat: I. Innate taste preferences and aversions.

Two experiments examined the innate taste preferences and aversions of rats with electrolytic lesions of the gustatory thalamus (GT). Contrary to previous research, GT lesions had only a minor influence on intake of the 4 basic tastes as assessed with the 24-hr, 2-bottle preference test in Experiment 1. The same lesioned rats, when tested with the same stimuli in the 15-min, single-bottle procedure in Experiment 2, showed normal consumption patterns except for sucrose intake, which was attenuated. The conflicting findings of previous and present research are considered to result from differences in lesion size. The current data suggest that the GT has a relatively minor functional role in the unconditioned acceptance or rejection of sapid stimuli.

Animals↗
PubMed1996

An exploration of feeding difficulties in children with Down syndrome.

Detailed examination of several aspects of feeding was carried out on a representative sample of a defined geographical population of children with Down syndrome. The examination included standardised assessments both of oral-motor function and of parent-child interaction. The findings suggest that the development of oral-motor function in children with Down syndrome not only lags behind intellectual development, but also follows an aberrant pathway. In particular, specific aspects of tongue and jaw function were impaired together with problems initiating and maintaining a smooth sequence of feeding actions. Also, parent-child interactions, as in studies on play, tended to be more controlling. Parents of children with Down syndrome do not spontaneously report the extent of their child's feeding problems unless specific enquiry is made, preferably accompanied by observation of feeding.

Child, Preschool↗
PubMed1996

The metamorphosis of feeding kinematics in Salamandra salamandra and the evolution of terrestrial feeding behavior

The striking similarity between aquatic feeding behaviors in fishes and tetrapods and terrestrial prey transports in tetrapods and their contrasts to terrestrial tongue projection kinematics have led to a general hypothesis that terrestrial prey capture evolved from terrestrial prey transport, which, in turn, evolved from aquatic feeding behavior. This hypothesis is examined in Salamandra salamandra by comparing the kinematics of prey capture and transport before and after metamorphosis in the same group of eight individuals. Kinematics of aquatic and terrestrial strikes and transports are used to describe the metamorphosis of feeding behavior in S. salamandra and provide the first kinematic description of both aquatic and terrestrial feeding behaviors in the family Salamandridae. On the basis of the shared characteristics among the four behaviors, the two aquatic behaviors are most similar, and these are more similar to terrestrial transports than to terrestrial strikes. Given the ontogenetic polarity of these behaviors in salamanders, I suggest, on the basis of the shared similarities and functional shifts, that terrestrial transport is an intermediate behavior between aquatic feeding and terrestrial tongue projection. These results support the hypothesis that a shift from aquatic feeding to terrestrial transport to terrestrial tongue projection represents an evolutionary transformation series in the evolution of terrestrial feeding in early tetrapods.

Journal Article↗
PubMed1996

Gustatory thalamus lesions in the rat: II. Aversive and appetitive taste conditioning.

The learning capacities of rats with electrolytic lesions of the gustatory thalamus (GT) were investigated in 3 experiments. In Experiment 1, the presence of a taste cue failed to overshadow odor aversion learning in the lesioned rats, yet these same animals acquired normal taste and odor aversions. Thalamic lesions had no discernible effect on the acquisition of a conditioned flavor preference in Experiment 2. Finally, GT lesions completely reversed the anticipatory contrast effect shown by control subjects in Experiment 3. These results suggest that damage to the GT spares taste detection and recognition and simple associative learning but interferes with learning that involves more complex gustatory information processing.

Animals↗
PubMed1995

The effect of thalamic lesions on primate taste preference.

Taste preferences and aversions were examined before and after the placement of bilateral, electrophysiologically guided electrolytic lesions of the thalamic taste area in five Old World monkeys. The only consistent changes shown by all lesioned monkeys on the 30-min, single-bottle intake test were a significantly attenuated consumption of 0.003 M quinine hydrochloride and a significantly elevated intake of 0.1 M sodium chloride. These specific taste deficits are contrary to the global hypogeusia predicted on the basis of previous research. A revised definition of the boundaries of the gustatory thalamus is suggested and the merits of the thalamic monkey preparation are compared with those of the decerebrate rat model.

Animals↗
PubMed1995

The objective rating of oral-motor functions during feeding.

The Schedule for Oral Motor Assessment (SOMA) was developed to record oral-motor skills objectively in infants between ages 8 and 24 months postnatal. Its aim is to identify areas of dysfunction that could contribute to feeding difficulties. The procedure takes approximately 20 min to administer, and is intended to be rated largely from a videorecording of a structured feeding session. A series of foodstuffs of varying textures, including liquids, is presented to the child in a standardized manner. Oral-motor skills are evaluated in terms of discrete oral-motor movements. The schedule distinguishes these from skills at more aggregated levels of functioning such as jaw, lip, and tongue control. A total of 127 children have been studied with the instrument, including normal healthy infants and samples with nonorganic failure to thrive, and cerebral palsy. Interrater and test-retest reliabilities were determined on a subset of 10 infants who each took part in three trials rated by 2 therapists. Excellent levels of interrater reliability (kappa > 0.75) were obtained for the presence/absence of 69% of discrete oral-motor behaviors. Test-retest reliability was similarly excellent for 85% of ratable behaviors. For the first time an assessment of oral-motor functioning has been shown to have adequate reliability for children aged 8-24 months. The validation of the SOMA on a large sample of normally developing infants and its application to clinical groups is presented in an accompanying paper [1].

Bottle Feeding↗
PubMed1995

Schedule for oral-motor assessment (SOMA): methods of validation.

The Schedule for Oral Motor Assessment (SOMA) was developed for the purpose of objectively rating the oral-motor skills of preverbal children, with a view to identifying areas of deficient abilities that could have clinical significance. The instrument can be administered without special equipment, by a trained observer. Oral-motor function is assessed across a range of food textures and fluids. Ratings of oral-motor skills are largely made post hoc by analysis of a videorecording of the test administration. The test-retest and interrater reliability of the instrument have been shown to be excellent. Criterion validity was investigated by means of a novel 'seeded cluster analysis' procedure in which 127 young children were assessed, most of whom were between 8 and 24 months of age. Ten percent of the sample had known abnormal oral-motor function in association with cerebral palsy (ages between 12 and 42 months). Not only was criterion validity satisfactorily established by the analysis but an abbreviated version of the SOMA--suitable for screening purposes--was developed. This has been shown to have a positive predictive validity greater than 90% and sensitivity greater than 85% for the detection of infants with clinically significant oral-motor dysfunction.

Cerebral Palsy↗
PubMed1995

Failure to thrive and the risk of child abuse: a prospective population survey.

OBJECTIVE: To identify the relative importance of failure to thrive during infancy as a risk factor for later abuse or neglect. DESIGN: Whole population birth cohort (1 January to 31 December 1986) studied prospectively over a four year period. SETTING: An inner city health district in London, England. SUBJECTS: 2609 births, of whom 47 were identified as having non-organic failure to thrive by first birthday. MAIN OUTCOME MEASURES: Registration on Child Protection Register, or subject to investigation of suspected abuse or neglect without registration. RESULTS: 2.5% (64) of birth cohort had been placed on the Child Protection Register during the period 1986-1990, and a further 1.2% (32) had been a cause for concern. The relative risk attributable to non-organic failure to thrive was 4.3 (95% CI 1.65 to 11.94) and exceeded other measured risk factors, including birth weight < 2500 g, 1.96 (95% CI 1.01 to 3.82); gestation < 35 weeks, 3.26 (95% CI 1.32 to 3.75); ordinal position > or = 4, 1.53 (95% CI 0.72 to 3.23). A multiple logistic regression confirmed the independent contribution of non-organic failure to thrive to subsequent poor parenting warranting professional intervention. CONCLUSIONS: Early postnatal non-organic failure to thrive is a risk factor for later serious parenting deficiencies, but previous research has overstated its importance. Within the community studied the nature of subsequent risk was (non-nutritional) neglect, rather than non-accidental injury. More than eight out of 10 cases do not give further cause for concern.

Age Factors↗
PubMed1995

The ontogeny of aquatic feeding behavior in Salamandra salamandra: stereotypy and isometry in feeding kinematics

To examine the extent to which aquatic prey-capture behavior in salamanders is stereotyped and how feeding kinematics scales with size, the ontogenetic variability of aquatic feeding behavior was examined in eight Salamandra salamandra. Feeding kinematics (seven duration and angular displacement variables), kinematic variance and capture performance were quantified and compared in the first several feedings after birth with a series of feedings 8 weeks later, just prior to metamorphosis. Analysis of variance revealed no statistically significant ontogenetic differences in the kinematic variables, and individual differences were found in only two variables (maximum gape angle and gape cycle time). A comparison of the relative kinematic variance within individuals revealed no significant differences in variance during ontogeny. In addition, capture success rate did not change. The strike is significantly faster than that of other salamanders. These results indicate that the initial prey-capture behavior remains unchanged throughout larval ontogeny. Thus, aquatic strike behavior in S. salamandra is developmentally fixed (innate) and does not appear to be influenced by learning or improvement in 'skill', supporting the hypothesis that aquatic salamander feeding is a highly stereotyped, unmodulated behavior. In addition, the lack of kinematic change through ontogeny indicates that feeding kinematics do not scale with body size, contrary to predictions that movements should be slower in larger animals.

Journal Article↗
PubMed1995

Discrimination training, partial reinforcement, and increases in intertrial interval all reduce response speed in a continuously reinforced key-pecking task.

Pigeons were trained in a discrete-trial task in which a response to the center key obtained illumination of a side key and a single response to the side key terminated a trial with either reinforcement or nonreinforcement. Center-key speeds (i.e., reciprocals of latencies) declined with increases in intertrial interval, and it is argued that this effect is related to a decreased likelihood as intertrial interval increases that birds will be near the key at trial onset. Side-key speeds on trials with reinforcement decreased both with increases in intertrial interval and with shifts from continuous reinforcement to either a discrimination or a partial-reinforcement condition. The effects on side-key speeds are compared with effects observed in alley-running tasks using rats, and an interpretation in terms of frustration theory is offered for the results obtained in both types of task.

Journal Article↗
PubMed1995

Impaired oral-motor function in children with Down's syndrome: a study of three twin pairs.

Three twin births occurring within 18 months in Oxfordshire, in which a girl with Down's syndrome was twin to an unaffected boy, provided an opportunity for a closely matched comparison of ratings on the Schedule for Oral Motor Assessment, which examines oral-motor function in a systematic and reliable way. A detailed description of the video-recording of one twin pair is included. This illustrates abnormalities of oral-motor function which may occur generally in Down's syndrome, as suggested further by a numerical tabulation of the differences found between the twins.

Child, Preschool↗
PubMed1994

A new gustometer for testing taste discrimination in the monkey.

A fully automated, 10-channel gustometer for use with nonhuman primates is described. The system, constructed primarily from commercially available components, includes an intelligence panel (containing sample spout, reward spout, and two operant response keys) that attaches to the door of a standard primate cage. The novel feature of the gustometer is a sample delivery spout that can be flushed, rinsed, and refilled within a specially designed rinsing chamber. All wetted surfaces of the gustometer are either Teflon, glass, or stainless steel. Flame photometric analysis confirmed the absence of cross-contamination between trials. Behavioral data collected from one rhesus monkey using a shock-suppression procedure demonstrates the detection threshold for sodium chloride. Improvements to the design, including the addition of pressurized sample delivery triggered by a lickometer circuit, are discussed.

Animals↗
PubMed1994

Taste preference of Old World monkeys: I. A single-bottle preference test.

There have been relatively few published reports of the taste preferences of nonhuman primates due, in part, to the expense and relative difficulty associated with maintaining a large group of these animals. The present report describes a version of the single-bottle preference test that can be used effectively with small groups of macaque monkeys. Experiment 1 determined the optimal durations for the pretest water deprivation period, the test trial itself, and the posttest rehydration period. Experiment 2 used this procedure to examine intake of the four prototypical gustatory stimuli. The results showed that cynomolgus monkeys, like other species, accept solutions containing sucrose and isotomic saline and reject those containing quinine hydrochloride. Unlike most other species, however, these monkeys do not find moderate concentrations of hydrochloric acid aversive.

Animals↗
PubMed1994

Postnatal growth and mental development: evidence for a "sensitive period".

For many years it has been suspected that severely impaired somatic growth during early postnatal life can be associated with the subsequent impairment of mental abilities. This study aimed to test that hypothesis on the basis of data gathered from a prospective whole population survey of infant development in south London. A year's birth cohort of 1558 full-term singletons was monitored; 47 otherwise healthy cases with serious growth faltering in the first year were recruited. Mental and psychomotor abilities were assessed at 15 months. Potentially confounding psychosocial variables, including cognitive stimulation received at home, were measured contemporaneously. A statistical model was constructed that enabled the timing, duration and severity of growth faltering to be used as predictors of mental functioning. Up to 37% of the variance in cognitive and psychomotor outcome at 15 months can be explained by the model. The first few postnatal months appear to constitute a "sensitive period" for the relationship between growth and mental development.

Anemia↗