Biomedical subjects

Christopher E Lalonde

Publications and source records attributed to Christopher E Lalonde.

3 recordsLinked to original sources

PubMed2006

Cognitive control in children: stroop interference and suppression of word reading.

The development of cognitive control and its relation to overcoming Stroop interference was assessed in a sample (N= 65) of elementary-school children. Subjects alternately performed Stroop color-naming trials and word-reading trials. In separate blocks, the colored Stroop items were non-color words (incongruent condition) or rows of asterisks (neutral condition). Younger children showed both larger Stroop interference in error rates and a greater slowing of word reading in the incongruent condition compared with older children. We conducted analyses of response time distributions that assessed the degree of word-reading suppression applied by younger and older children. Surprisingly, these analyses indicated that younger children engaged in stronger suppression than older children. We propose that greater Stroop interference among younger children is not due to lack of ability to suppress word reading, but instead is the result of a failure to consistently maintain the task set of color naming.

Child↗

PubMed2004

Children's persistence with methylphenidate therapy: a population-based study.

OBJECTIVE: To examine persistence with methylphenidate (MPH) therapy among children and youth in the general population. METHOD: We conducted a retrospective analysis of longitudinally organized, individual-specific anonymous data from linked prescription and health databases covering the population of British Columbia for 1990 through 1996. No prescriptions being filled for 4 months indicated cessation of one bout of therapy. RESULTS: Among 16,945 identified MPH patients aged 19 years or under, overall duration of therapy was 584 days, and the average number of prescriptions received was 6.6. One-third of patients received 2 or fewer prescriptions, while 18% followed a chronic, continuous course. Among patients receiving more than 2 prescriptions, 50% of discrete therapy bouts lasted 4 months or less, and one-third of cases had multiple bouts of therapy (range 2 to 6 bouts). Younger age (that is, children aged 0 to 8 years, vs those aged 10 to 19 years), male sex, and receipt of initial prescription from a psychiatrist were associated with greater persistence. CONCLUSIONS: Enormous variability in persistence with MPH therapy and often-occurring low rates of persistence raises questions about the diligence with which MPH patients are selected, prepared, and followed in the general population. Special attention to the needs of older children and to the needs of girls is required, and discontinuities during children's therapy courses require explication.

Adolescent↗

PubMed2003

Personal persistence, identity development, and suicide: a study of Native and Non-native North American adolescents.

The cross-cultural program of research presented here is about matters of temporal persistence--personal persistence and cultural persistence--and about solution strategies for solving the paradox of "sameness-in-change." The crux of this paradox resides in the fact that, on threat of otherwise ceasing to be recognizable as a self, all of us must satisfy at least two constitutive conditions. The first of these is that selves are obliged to keep moving or die, and, so, must continually change. The second is that selves must also somehow remain the same, lest all notions of moral responsibility and any commitment to an as yet unrealized future become nonsensical. Although long understood as a problem demanding the attention of philosophers, we argue that this same paradox arises in the ordinary course of identity development and dictates the different developmental routes taken by culturally mainstream and Aboriginal youth in coming to the identity-preserving conclusion that they and others are somehow continuous through time. Findings from a set of five studies are presented. The first and second studies document the development and refinement of a method for parsing and coding what young people say on the topic of personal persistence or self-continuity. Both studies demonstrate that it is not only possible to seriously engage children as young as age 9 or 10 years in detailed and codable discussions about personal persistence, but that their reasoning concerning such matters typically proceeds in an orderly and increasingly sophisticated manner over the course of their early identity development. Our third study underscores the high personal costs of failing to sustain a workable sense of personal persistence by showing that failures to warrant self-continuity are strongly associated with increased suicide risk in adolescence. Study four documents this same relation between continuity and suicide, this time at the macrolevel of whole cultures, and shows that efforts by Aboriginal groups to preserve and promote their culture are associated with dramatic reductions in rates of youth suicide. In the final study we show that different default strategies for resolving the paradox of personal persistence and change--Narrative and Essentialist strategies--distinctly characterize Aboriginal and non-Aboriginal youth.

Adolescent↗