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Biomedical subjects

S Reilly

Publications and source records attributed to S Reilly.

At least 91 records · Page 5Linked to original sources
PubMed1989

Medial versus lateral hyperstriatal lesions in pigeons: effects on autoshaping, non-matching-to-sample and spatial discrimination learning at short and long intertrial intervals.

Three experiments contrasted the effects of medial and lateral hyperstriatal lesions in pigeons. Expt. 1 found that both types of lesion obtained slower acquisition of autoshaping, compared to unoperated controls. No group differences in maintained rate of autoshaped responding were found. Expt. 2 found that lateral but not medial lesions disrupted choice performance in a non-matching-to-sample (NMTS) task, in which initial preference was for the correct stimulus; birds with lateral lesions responded more slowly to the sample stimulus than did birds with medial lesions. Expt. 3 found that medial but not lateral lesions disrupted both acquisition and reversal of a spatial discrimination at a long, but not at a short intertrial interval (ITI). Medial lesions damage primarily the hyperstriatum accessorium and lateral lesions, the hyperstriatum ventrale; but no significant correlations between the extent of damage to either of these structures and severity of behavioural disruption were obtained. Implications of these findings for theoretical accounts of hyperstriatal involvement in learning processes are discussed.

Animals↗
PubMed1989

Attenuation of conditioned taste aversions by external stressors.

Conditioned taste aversions (CTAs) were produced by low doses of toxins injected 30 or 60 min after rats finished drinking saccharin solution. Attempts were made to attenuate these CTAs by subjecting the rats to stress or to injections of glucocorticoids (primarily dexamethasone) during the interval between saccharin consumption and injection of the toxin. The stressors used were statistically indistinguishable in their effects: swimming, constant footshock (for 2 min), or intermittent footshock (for 10 min). The extent to which different agents attenuated CTAs depended on which toxin was used to produce the CTA as follows. The stressors produced marked CTA attenuation when lithium was the toxin, but none when cisplatin was the toxin. The glucocorticoids exhibited an opposite pattern of marginal CTA attenuation with lithium and marked CTA attenuation with cisplatin. CTAs produced by morphine were more like those produced by cisplatin than like those produced by lithium. Our belief that the CTA attenuation demonstrated here indicates alleviation of the distress produced by the toxin was supported by the results of the final two experiments as follows: 1) The stress does not raise saccharin preference independently of interference with the aversiveness of the toxin since, in similar experiments in which toxins were not administered, footshock administered in conjunction with exposure to saccharin solution reduced later saccharin preference. 2) Probably CTA attenuation does not occur because stress interferes with the taste-toxin association since footshock administered before the saccharin drinking session (instead of after it) also produced CTA attenuation.

Animals↗
PubMed1989

Hippocampal lesions and associative learning in the pigeon.

The performance of pigeons with hippocampal lesions was compared with that of unoperated and neostriatal-lesioned control Ss in 3 experiments. In Experiment 1, hippocampal-lesioned birds were retarded in the acquisition and the maintenance levels of autoshaped responding. However, the deficit was attenuated following the addition of a response contingency to the autoshaping schedule. In Experiment 2, the hippocampal-lesioned birds showed impaired performance on a differential reinforcement of low rates of responding schedule. From the high levels of responding in Experiment 2, underresponding was observed in hippocampal-lesioned birds relative to control Ss on return to the autoshaping schedule in Experiment 3. Results are interpreted in terms of impaired classical conditioning in hippocampal-lesioned birds.

Animals↗
PubMed1989

Oral-motor dysfunction and failure to thrive among inner-city infants.

Non-organic failure to thrive among socio-economically deprived inner-city infants may be associated with abnormal oral-motor functioning and aspects of social adversity, such as disorganised meal-times. A Feeding Assessment Schedule was devised to rate oral-motor behaviour objectively and was used to test nine pairs of case and comparison children while they were being fed at home. Video-recordings were made for later analysis. The case infants had immature and abnormal oral-motor development that made them less able to be fed successfully. Temperamentally they were more 'difficult' than the comparison infants, and they were less adept at signalling their needs during meal-times. The case infants also were fed in inappropriate positions for their age, with more distractions and less suitable utensils.

Child↗
PubMed1988

Hyperstriatal lesions and classical conditioning in the pigeon.

In two experiments, pigeons with bilateral lesions of the hyperstriatum were compared with unoperated control birds and operated control subjects having bilateral lesions of the neostriatum on tasks designed to test two hypotheses of hyperstriatal function. In Experiment 1, hyperstriatal lesions impaired both the acquisition and maintenance of autoshaped responding as well as maintenance responding in response-omission training. In Experiment 2, hyperstriatal birds displayed depressed levels of responding relative to control birds on a classical go-no-go alternation schedule. These results support the view that hyperstriatal selectively disrupt classical conditioning and go against the view that hyperstriatal lesions exaggerate perseverative responding. A surprising aspect of the results was the performance of the operated control subjects that showed better performance in the acquisition of autoshaping and superior differentiation on the go-no-go schedule compared with the unoperated control birds.

Animals↗
PubMed1988

Assessment of the outcome of low back surgery.

We aimed to develop a better understanding and method of rating the success or failure of low back surgery by studying 185 patients prospectively. Identical pre-operative and postoperative assessment by an independent observer included pain, disability, physical impairment, psychological distress and illness behaviour. Outcome was assessed by the patient, by the observer and by return to work. There was 96% follow-up at two years. Correlation co-efficients varied considerably between the various measures of outcome, both patient and observer appearing to base their assessment mainly on postoperative status rather than on any change produced by surgery. The observer was influenced most by postoperative pain, disability and physical impairment. Patients were influenced most by residual physical impairment, type of surgery and proportional change in disability. Return to work was moderately influenced by postoperative disability and to a larger extent by social and work-related factors. We developed a simple formula to judge overall success or failure which accurately reproduced the combined assessment of patient and observer. If surgical audit is to be meaningful it must be based on an improved understanding of how the outcome of surgery should be assessed.

Activities of Daily Living↗
PubMed1987

Hyperstriatal lesions and attention in the pigeon.

In two experiments, pigeons with bilateral lesions of the hyperstriatum were compared with unoperated control birds on tasks designed to test an attentional account of hyperstriatal function. In both experiments, hyperstriatal lesions disrupted reversal learning but did not influence the retardation of learning associated with either nonreinforced preexposure to the to-be-conditioned stimulus (Experiment 1) or prior nondifferential reinforcement to the to-be-discriminated stimuli (Experiment 2). There was, however, evidence of an impairment in both the acquisition and maintenance of autoshaped responding in lesioned birds, an impairment which may reflect a disruption of classical associations in hyperstriatal pigeons.

Animals↗
PubMed1987

Double dissociation of effects on learning of medial versus lateral hyperstriatal lesions in pigeons.

Three experiments examined the effects of medial and lateral hyperstriatal lesions in two groups of pigeons. In Experiment 1, both hyperstriatal groups were impaired, relative to unoperated and operated control groups, in postoperative performance of preoperatively acquired serial reversal of both spatial and visual discriminations. The deficits of the two hyperstriatal groups appeared both quantitatively and qualitatively similar. Experiment 2 found that performance of spatial reversals was disrupted in the medial, but not in the lateral, hyperstriatal group by a long intertrial interval. Experiment 3 found that acquisition of simultaneous matching-to-sample was disrupted by lateral, but not by medial, hyperstriatal lesions; the lateral group also showed a lower rate of response to the sample stimulus than any of the other groups. Implications of these findings for current theories of hyperstriatal function are discussed.

Animals↗
PubMed1986

Adenovirus type 8 keratoconjunctivitis--an outbreak and its treatment with topical human fibroblast interferon.

An outbreak of keratoconjunctivitis is described which involved at least 186 people; adenovirus type 8 was identified in 50 of the cases. Topical human fibroblast interferon was assessed in a double-blind, placebo-controlled study in which 34 patients participated. Seventeen of the 34 trial patients yielded adenovirus type 8; three were infected with adenovirus type 7. The outbreak was curtailed by control of infection measures: principally careful hand-washing by medical personnel between cases and by discouraging attendance of new cases at the Eye Infirmary. Consequently the trial numbers are small. In addition there was a wide interpatient variation in the severity of infection. Therefore it was not possible to make any statistically valid conclusions concerning the recovery rate of patients receiving interferon or placebo.

Adenoviridae Infections↗
PubMed1985

Human papillomavirus infection of the esophagus. A clinicopathologic study with demonstration of papillomavirus antigen by the immunoperoxidase technique.

Papillomaviruses are known to be oncogenic in animals. In humans they are associated with benign squamous tumors (verruca, condylomata acuminata, and papillomas) in a variety of body sites. Human papillomavirus (HPV) infection of the esophagus, however, has not previously been documented. Recent reports of condylomatous changes in esophageal epithelium adjacent to esophageal carcinoma and the sporadic descriptions of esophageal papillomas in the literature for many years, lend credence to the assumption that HPV may affect the squamous mucous membrane of the esophagus. In the current study 75 cases, including 2 papillomas and 73 focal epithelial hyperplasia of the esophagus, were examined for histologic evidence of HPV infection as characterized by the presence of koilocytosis, giant and multinucleated cells, dyskeratosis, hyperkeratosis, acanthosis, papillomatosis, and anisonucleosis. Thirteen of the cases--the 2 papillomas and 11 of the focal epithelial hyperplasias--contained distinctive histologic evidence of HPV infection. The presence of HPV antigens was demonstrated by immunoperoxidase (IMPO) in the 4 of the 13 cases (31%). In the remaining cases the IMPO was equivocal in two and negative in seven.

Adult↗
PubMed1983

Probability learning in pigeons (Columba livia) is not impaired by hyperstriatal lesions.

Three experiments investigated the effects of hyperstriatal lesions on spatial and visual probability learning in pigeons. The lesions did not affect choice accuracy although they did reduce positional responding on error trials in the visual task. The results gave support to a perseverative, as opposed to an attentional, interpretation of the lesion effects. Increasing intertrial interval in the visual task resulted in decreased accuracy in both lesion and control groups, and the absence of a differential effect on the lesioned birds ran counter to an earlier suggestion that increased perseveration might be due to increased frustration. A fourth experiment confirmed that the lesions disrupted both acquisition and reversal of a conventional orientation discrimination; the deficits again appeared to be due to increased perseveration rather than to shifts in attention.

Analysis of Variance↗
PubMed1981

Possible role of the anaerobe in tonsillitis.

Anaerobic bacteria were isolated from all tonsils removed from children at routine tonsillectomy; 75.6% of specimens yielded moderate to heavy growth and 80% of tonsils contained more than one anaerobic species. This recovery rate fell to 56% after a 10-day course of metronidazole before tonsillectomy--in only 14.6% of cases were anaerobes isolated in significant numbers. Surface swabbing of the tonsils permitted recovery of a similar spectrum of anaerobic bacteria but resulted in an overall loss of both aerobic and anaerobic pathogens. A comparison was made between the flora of acutely inflamed tonsils and "healthy' tonsils: over 90% of both groups yielded anaerobic bacteria, but they were present in significant numbers in 56.2% of swabs taken from acutely inflamed tonsils compared with 24% of swabs from "healthy' children. The isolation rate for anerobic pathogens was 37.5% and 16% respectively.

Acute Disease↗