Biomedical subjects

Pria M D Nippak

Publications and source records attributed to Pria M D Nippak.

4 recordsLinked to original sources

PubMed2006

Extensive spatial training does not negate age differences in response latency.

Previously, Nippak et al. [Nippak, P.M.D., Chan, A.D.F., Campbell, Z., Muggenburg, B., Head, E., Ikeda-Douglas, C., Murphy, H., Cotman, C.W., Milgram, N.W., 2003. Response latency in the canine: mental ability or mental strategy? Behav. Neurosci. 117 (5), 1066-1075] reported that young dogs respond significantly slower than aged dogs during the acquisition of a three-component delayed non-match to position (3-DNMP) task. Thus, we examined how age influences response latency (RL) when animals are trained extensively on the 3-DNMP task. Animals were separated into two groups based on their task sophistication. The first group comprised young (N=5) and aged (N=10) dogs that received extensive spatial training on a two-component delayed non-match to position task (2-DNMP) before 3-DNMP testing, while the second group of young (N=8) and aged (N=11) animals received extensive training on a variety of other non-spatial cognitive tasks between each 3-DNMP test period. RL age differences were absent following extensive 3-DNMP testing; however, other age-dependent performance differences emerged: all young animals learned the task and displayed RL slowing and superior response accuracy (RA) on the center-incorrect (CI) subtest, while several aged animals failed to learn the task and displayed no RL or RA subtest variations even when they acquired the task. Toates's [Toates, F., 1998. The interaction of cognitive and stimulus-response processes in the control of behaviour, Neurosci. Biobehav. Rev. 22 (1), 59-83] theory of RL and mental strategy was proposed to explain these age differences in response strategies: the fast-responding aged animals utilized stimulus-response strategies, while the slow-responding young animals adopted cognitive strategies, a specific requirement for solving the CI subtest.

Aging↗

PubMed2005

An investigation of the relationship between response latency across several cognitive tasks in the beagle dog.

Response latencies (RLs) extracted from simple motor tasks are a commonly used index of human intelligence. To date few human or animal studies have investigated the relationship between an individuals RL scores across a number of diverse cognitive tasks: Does RL remain consistent between individuals across several cognitive domains? Thus, the current study examined how RL measures gathered from beagle dogs (n=13) tested on three different cognitive tasks were related. RL scores were collected following both discrimination and reversal learning and a test of visuospatial memory, the 3 component delayed non-matching to position (3-DNMP) task. RL scores were recorded from the time the choice stimulus was presented until the animal selected a response. Results indicated that strong correlations emerged between 3-DNMP RLs and both the discrimination and reversal RLs, indicating that animals that responded fast on the 3-DNMP task also responded fast on the discrimination and reversal tasks. Interestingly, 3-DNMP RLs were more strongly correlated with reversal learning RLs. Finally, when mean RL performance across the three tasks was examined, strong RL differences emerged indicating that animals displayed significantly slower RLs on the 3-DNMP task than on the discrimination task, while reversal RLs remained indistinguishable from both. In conclusion, RLs show high between task correlations, indicating individual differences, and also vary between tasks, probably because of differences in task difficulty. These results further validate the use of RLs as an index of cognition, and also highlight the importance of further studies using animal models.

Animals↗

PubMed2003

Response latency in Canis familiaris: mental ability or mental strategy?

Animal studies of cognitive aging typically use measures of response accuracy (RA) to evaluate cognitive function, which declines with age. Human aging studies, by contrast, frequently measure response latency (RL), with faster responses being indicative of superior performance. To examine the influence of age on RL in an animal model, the authors assessed RA with RL in young and aged beagle dogs (Canis familiaris) tested on a 3-component delayed nonmatching-to-position task, which comprised 3 subtests. Young dogs displayed significantly slower RLs and higher RAs and showed RL slowing with greater complexity, compared with aged dogs. In addition, the slower responding young dogs made fewer errors. Thus, RL appears to reflect the learning strategy applied, rather than the level of mental ability.

Aging↗

PubMed2002

Visuospatial impairments in aged canines (Canis familiaris): the role of cognitive-behavioral flexibility.

This study used a novel delayed nonmatching-to-position task to compare visuospatial learning and memory in young and aged beagle dogs (Canis familiaris). The task used 3, rather than 2, spatial locations, which markedly increased difficulty. There were striking age differences in acquisition. Most of the aged canines did not learn the task, and those that did showed impaired learning when compared with the young canines. The aged canines also showed reduced maximal working memory capacity compared with the young canines. Analysis of the response patterns of individual canines indicated that the deficits were related to the use of ineffective strategies and inflexibility in strategy modification.

Aging↗