Biomedical subjects

D M Lane

Publications and source records attributed to D M Lane.

9 recordsLinked to original sources

PubMed1991

Auditory attention switching in hyperactive children.

The ability to rapidly reorient attention in the auditory modality was studied in hyperactive children. Hyperactive and nonhyperactive subjects matched on age, sex, and IQ listened to dichotically presented lists for prespecified targets. Reorientation was studied by comparing performance on trials requiring subjects to reorient their attention during a list to performance on trials requiring no switching of attention. The results indicate that although nonhyperactive children were temporarily disrupted by the switch, they eventually reoriented to the cued ear. In contrast, once hyperactive children were disrupted by the switch, they did not reorient to the cued ear. As the pattern in performance comparing hyperactive and nonhyperactive subjects resembles the pattern previously found in comparing younger and older subjects, these results are consistent with the hypothesis that the auditory reorientation skills of hyperactive children are developmentally immature.

Acoustic Stimulation↗

PubMed1991

Auditory attention switching: a developmental study.

The developmental course of the ability to rapidly allocate attention was studied using a dichotic listening task with 8-year old, 11-year old and college age subjects. In this task, subjects were instructed to listen to one ear for predescribed targets and then were later signaled (on some trials) to switch their attention to the other ear. Reorientation was assessed by comparing the pattern of subjects' omission and intrusion errors on trials following a command to switch ears with the pattern of errors on no-switch trials. Older subjects were better able to reallocate their attention in accordance with task demands, with the greatest gains in performance occurring between ages 8 and 11. This developmental change appears to be generally continuous and quantitative in nature. Since successful performance of this task requires flexibility in subjects' ability to control their focus of attention, these results support the hypothesis that the basis of the developmental improvement in the ability to ignore irrelevant information is linked to the ability to use active attentional strategies.

Adolescent↗

PubMed1991

Afibrinogenemia and hypobetalipoproteinemia in a kindred.

A 3-year-old boy with minor bleeding problems had no plasma fibrinogen measured by both clottable assay and immuno-precipitation. Low normal fibrinogen levels were present in the mother and father. Markedly decreased plasma cholesterol and apolipoprotein B levels were found in the father, proband's brother, and the paternal side of the kindred. The proband and his mother had normal plasma total cholesterol and apolipoprotein B levels. These findings are compatible with autosomal dominant transmission of hypobetalipoproteinemia and autosomal recessive transmission of afibrinogenemia. Two members of the father's family had plasma cholesterol levels below the fifth percentile but elevated levels of fibrinogen (6.0 and 4.4 g/L). Both have symptomatic coronary heart disease. Finding coronary heart disease with very low cholesterol but elevated fibrinogen levels is consistent with fibrinogen levels being an independent risk factor for coronary heart disease.

Adult↗

PubMed1990

Sex differences in the personality and cognitive correlates of spatial ability.

Ozer (1987) found that spatial visualization correlated with personality and verbal ability for girls but not for boys. To account for this finding, he hypothesized that "the causes of individual differences in spatial visualization [may be] different for the two sexes" (Ozer, 1987, p. 134). Although Ozer's conclusion is an intriguing one, it should be viewed with at least some skepticism until the discrepancies between his data and those of other researchers have been reconciled.

Adult↗

PubMed1990

Visual attention movements: a developmental study.

The pattern of attention movements underlying reorientation of visual selective attention independent of eye movements was studied developmentally in 2 experiments. In Experiment 1, 8-year-old, 11-year-old, and college-age subjects first oriented their attention to a central location and were then cued to direct their attention either to the left or the right peripheral field. Following variable intervals, the target appeared at the cued location and reaction times were recorded. The data were interpretable in terms of the attentional spotlight theory since there was an interaction between distance of the target from fixation and SOA. In terms of this theory, the data indicate that the velocity of attention movements increases throughout the age range studied. Experiment 2, in contradiction to attentional spotlight theory, failed to find evidence of an interaction between distance and SOA. This experiment suggested that young children can covertly orient their attention by including valid, neutral, and invalid cues, and that these cues can both facilitate and inhibit attentional orientation. This experiment also extended the findings to central as well as peripheral cues.

Adolescent↗

PubMed1977

Effects of continuous or discontinuous maintenance therapy on subsequent remission maintenance in childhood leukemia.

This study was designed to determine if resistance to a standard drug during the second remission of children with acute leukemia was reduced by discontinuation of therapy during the initial remission. The initial maintenance therapy was either 6-mercaptopurine (6-MP), methotrexate (MTX), or cyclophosphamide (CYC) given continuously to relapse or discontinued (at random) at 2 or 6 months. Following the initial relapse and after induction of a second complete remission, 72 evaluable patients received (continuously to relapse) either 6-MP (53 patients) or CYC (19 patients) for the second remission maintenance. Resistance of 6-MP occurred during the second maintenance, regardless of the drug used during the initial maintenance, in that the length of second remissions was significantly shorter than the length of first remissions. However, this resistance was most pronounced in patients who initially relapsed while on continuous 6-MP maintenance (medium duration of remission [MDR] of 9 weeks). Patients whose initial relapse occurred after the discontinuation of 6-MP had a MDR of 23 weeks and patients whose second remission was maintained with CYC (after relapse from initial continuous remission on 6-MP) had a MDR of 25 weeks.

Acute Disease↗

PubMed1975

Interrupted vs. continued maintenance therapy in childhood acute leukemia.

A total of 313 patients with childhood acute leukemia received a combination of vincristine (2 mg/m2/week) and prednisone (60 mg/m2/day); 86% of 276 evaluable patients achieved a complete bone marrow remission in a median of 35 days. When a complete bone marrow remission was achieved, patients were randomized to one of three oral maintenance therapies: 6-mercaptopurine (6MP) (75 mg/m2/day), methotrexate (MTX) (25 mg/m2/twice weekly), or cyclophosphamide (CYC) (100 mg/m2/day). Patients receiving maintenance therapy were further randomized at 2 and 6 months after the start of maintenance either to continue or discontinue therapy. tthe median lengths of subsequent bone marrow remission for patients randomized at 2 months to continue vs. discontinue therapy were: 37 vs. 19 weeks for 6-MP patients; 25 vs. 14 weeks for MTX patients; and 29 vs. 13 weeks for CYC patients. The median lengths of subsequent marrow remissions for patients receiving maintenance therapy for 6 months and randomized to continue vs. discontinue were: 57 vs. 17 weeks for 6-MP patients; 60 vs. 40 weeks for MTX patients; and 23 vs. 10 weeks for CYC patients. Results indicate a significant advantage for continuing maintenance therapy at 2 and 6 months after the start of complete bone marrow remission.

Acute Disease↗

PubMed1975

Long-term results of reinforcement therapy in children with acute leukemia.

A total of 180 children with acute leukemia was randomized to one of two induction regimens: vincristine plus prednisone, or 6-mercaptopurine plus prednisone. Of 170 patients evaluable for induction therapy, a hematologic remission was achieved in 83% (72/87) on vincristine plus prednisone, and in 93% (77/83) on 6-mercaptopurine plus prednisone. When hematologic remission was achieved, patients were randomized to one of three maintenance schedules: 6-mercaptopurine alone, 6-mercaptopurine plus prednisone for 4 weeks every 3 months, or 6-mercaptopurine plus prednisone plus vincristine for 4 weeks every 3 months. The durations of hematologic remission were compared from the achievement of hematologic remission to bone marrow relapse. The survival data were presented as an overview of the effect of this initial therapy on duration of survival. There was no statistical difference between the two induction regimens. The most important finding in the comparison of the three maintenance schedules was that reinforcement of 6-mercaptopurine maintenance therapy with either prednisone or prednisone plus vincristine resulted in significantly longer durations of remission. Vincristine added to prednisone for reinforcement after induction of remission by vincristine plus prednisone did not increase the duration of hematologic remission or survival over prednisone reinforcement alone.

Acute Disease↗

PubMedDate not supplied

Combined chemotherapy in childhood rhabdomyosarcoma.

Twenty-two children with rhabdomyosarcoma were treated with combination chemotherapy using vincristine, actinomycin D, and cyclophosphamide for varying time periods. Chemotherapy, usually combined with radiation therapy, was given to early stage patients after they had had a com plete or partial tumor resection. Three of nine patients who had widespread metastatic (stage III) disease at initiation of therapy had complete tumor regression and four of nine had partial tumor regression. However, the median durations of response and survival were brief (3 and 8 months respectively). Five patients with localized resectable (stage I) disease have survived without evidence of tumor recurrence from 33 to 69 months after their initial diagnosis. Of eight patients with incompletely resected regional (stage IIB) disease, one has survived without disease recurrence for 36 months, thought the median survival time of the remaining seven patients was 14 months. In stage IIB patients the duration of response was proportional to the duration of chemotherapy which suggests that chemotherapy should be given for at least 18-24 months.

Adolescent↗