Allocentric spatial performance higher in early-blind and sighted adults than in retinopathy-of-prematurity adults

The question as to whether people totally blind since infancy process allocentric or ‘external’ spatial information like the sighted has caused considerable debate within the literature. Due to the extreme rarity of the population, researchers have often included individuals with Retinopathy of Prematurity (RoP – over oxygenation at birth) within the sample. However, RoP is inextricably confounded with prematurity per se. Prematurity, without visual disability, has been associated with spatial processing difficulties. In this experiment, blindfolded sighted and two groups of functionally totally blind participants heard text descriptions from a survey (allocentric) or route (egocentric) perspective. One blind group lost their sight due to retinopathy of prematurity (RoP – over oxygenation at birth) and a second group before 24 months of age. The accuracy of participants’ mental representations derived from the text descriptions were assessed via questions and maps. The RoP participants had lower scores than the sighted and early blind, who performed similarly. In other words, it was not visual impairment alone that resulted in impaired allocentric spatial performance in this task, but visual impairment together with RoP. This finding may help explain the contradictions within the existing literature on the role of vision in allocentric spatial processing.

Task Competency in the Rights Analytic: Mental Health and the Justification for Rights and Duties

The paper concerns the moral status of persons for the purposes of rights-holding and duty-bearing. Developing from Gewirth’s argument to the Principle of Generic Consistency (PGC) and Beyleveld et al.’s Principle of Precautionary Reasoning, I argue in favour of a capacity-based assessment of the task competencies required for choice-rights and certain duties (within the Hohfeldian analytic). Unlike other, traditional, theories of rights, I claim that precautionary reasoning as to agentic status holds the base justification for rights-holding. If this is the basis for generic legal rights, then the contingent argument must be used to explain communities of rights. Much in the same way as two ‘normal’ adult agents may not have equal rights to be an aeroplane pilot, not all adults hold the same task competencies in relation to the exercise of the generic rights to freedom derived from the PGC. In this paper, I set out to consider the rights held by children, persons suffering from mental illness and generic ‘full’ agents. In mapping the developing ‘portfolio’ of rights and duties that a person carries during their life we might better understand the legal relations of those who do not ostensibly fulfil the criteria of ‘full’ agent.