Maturation Of Reflexes Research Articles

The maturation of cutaneous reflexes studied in man : H.C. Issler and J.A. Stephens (London, GB)

The maturation of cutaneous reflexes studied in man : H.C. Issler and J.A. Stephens (London, GB)

Maturation of reflexes influencing inspiratory duration in human infants.

Maturation of reflexes influencing inspiratory duration in human infants.

The maturation of the E.E.G. and sleep; genetic and environmental factors (author's transl)

Whilst studying the post-natal maturation of reflexes, EEG activity, rhythmic activity in Slonaker's wheels and the learning of adult mice, strains showing less pronounced rhythmic activity and more immature EEG and reflexes at birth were discovered. On the other hand some strains having a shorter post-natal period manifest an early maturation of their central nervous system. The results indicate that complex interactions exist between genotype and environment when the different post-natal maturation appearances are considered and that EEG activity may be useful in assessing development.

Postnatal development of laryngeal reflexes in the dog.

An investigation of laryngeal reflex maturation was undertaken in the dog to identify its period of most rapid postnatal differentiation. The canine model was selected because of its laryngeal reflex similarity to that of the human being. Observations in the dog indicate maximum differentiation to occur 1 to 1 1/2 months postnatally, based on measurements of recurrent laryngeal nerve myelination and conduction velocity. Latency and threshold analyses of evoked laryngeal responses additionally confirm this viewpoint. The importance of these observations rests in an understanding of developmental upper respiratory tract mechanisms that may be chronologically related to causes of fatal ventilatory events producing unexplained infant death. Such a correlation, requiring further confirmation, is based on the assumption that a critical period of most rapid development allows a transient susceptibility to noxious influences that can cause a disruption in organ function and even death of that organism itself.

Aversive prenatal stimulation: effects on behavioral, biochemical, and somatic ontogeny in the rat.

Electric foot shock administered to pregnant rats altered the ontogeny of spontaneous motor activity in their pups. Prenatally stimulated (PMS) offspring were more active than controls on Days 1-10 but less active during the 3rd postpartum week. The age of peak activity, a major developmental landmark, occurred in PMS pups around 10 days of age; in controls maximum activity was not seen until the 3rd week. This effect was independent of the gender of the offspring and the timing of the gestational stimulation. Its appearance in both cross-fostered and fostered pups indicated the prenatal origin of the effect. The maturation of spontaneous alternation behavior and several reflexes and the appearance of physical features were not affected by prenatal stimulation. Moreover, both PMS and control groups exhibited an age-related increase in brain concentrations of norepinephrine, serotonin, and 5-hydroxyindoleacetic acid. These findings indicate that spontaneous motor activity is uniquely sensitive to PMS, and as far as can be determined here, PMS produces no generalized alteration in behavioral and physical ontogeny.

Influence of lung inflation on respiratory control in neonates.

Influence of lung inflation on respiratory control in neonates.