RESUMEN
BACKGROUND: Due to newborn screening and early treatment, patients with phenylketonuria (PKU) and mild hyperphenylalaninemia (mHPA) develop largely normal, in terms of IQ testing and academic attainment. However, the impact of metabolic control in various stages of development on more complex cognitive abilities, i.e. executive functions (EF), is still unclear. METHODS: EFs were tested in 28 patients with PKU/mHPA, aged 8-17 years, identified by newborn screening and continuously treated. The relation to current (testing day & past 10 phenylalanine (Phe) values) and long-term metabolic control (age periods: childhood <6, 6-10, adolescence >10 years, lifetime Phe) was analyzed. RESULTS: EFs were in the lower normative range (IQR of T-values: 47.35-51.00). Patients reaction time was significantly slower than the population mean (divided attention/TAP: median 40, p < 0.01). Both, long-term and current metabolic control correlated with performance in EF tests: Higher current Phe impaired reaction times (Go/No-Go, r = -0.387; working memory, r = -0.425; p < 0.05) and performance in planning ability (ToL r = -0.465, p < 0.01). Higher long-term Phe values both in childhood and adolescence mainly affected attention (omissions/TAP r = -0.357 and - 0.490, respectively, both p < 0.05) as well as planning ability (ToL r = -0.422 and - 0.387, adolescence and lifetime, p < 0.05). CONCLUSION: Current and long-term metabolic control in PKU/mHPA, including the adolescent period, influence EFs, especially affecting reaction time and planning abilities. This should be taken into account in patient counselling.
RESUMEN
Access to and control of resources is a major source of costly conflicts. Animals, under some conditions, respect what others control and use (i.e. possession). Humans not only respect possession of resources, they also respect ownership. Ownership can be viewed as a cooperative arrangement, where individuals inhibit their tendency to take others' property on the condition that those others will do the same. We investigated to what degree great apes follow this principle, as compared to human children. We conducted two experiments, in which dyads of individuals could access the same food resources. The main test of respect for ownership was whether individuals would refrain from taking their partner's resources even when the partner could not immediately access and control them. Captive apes (N = 14 dyads) failed to respect their partner's claim on food resources and frequently monopolized the resources when given the opportunity. Human children (N = 14 dyads), tested with a similar apparatus and procedure, respected their partner's claim and made spontaneous verbal references to ownership. Such respect for the property of others highlights the uniquely cooperative nature of human ownership arrangements.