Abstract:

This paper reports on the results from a series of experiments in the field of spatial coding in terms of different conceptual reference systems. The users of these experiments were individuals with visual impairments. Based on relevant literature review, there are two frames of conceptual reference systems pertinent to spatial recognition and coding: a. the allo-centric which is referred to the nearby space of the individual, and b. the ego-centric which is based on the person. Although there is limited research on the reference system that is used by individuals with visual impairment, nevertheless, it is considered one of the important factors that should be taken into account by educators and trainers of mobility and orientation during their teaching instruction.

The research objectives of the present study are the following: a. to describe the type of the conceptual reference system that individuals with visual impairments use when they actively manipulate geometric shapes, and b. to explore relationships between type of geometric shape (two and three dimensional, simple or complex) and conceptual reference system.

Twelve individuals with total loss of vision (eight congenitally blind and four adventitiously blind) participated in the present study. All participants were asked to explore haptically by both hands two- and three dimensional shapes. The stimulus material was a wide range of simple and complex shapes (42 in total). The participants were informed that the whole process would be video-recorded and that the camera shot would focus only on their hands. The research design of the study had a structure similar to that of experiments.

The analysis of the data revealed that the participants who were blind from birth (congenitally blind) had the tendency to use both type of reference systems to explore the geometrical shapes in contrast to the adventitiously blind who primarily based their active exploration on the allo-centric frame of reference (1st research objective).

In addition, the participants who were congenitally blind seemed to have a preference to ego-centric conceptual reference frameworks when the shapes were complex, whereas participants who were adventitiously blind adopted allo-centric conceptual reference frameworks for all kinds of shapes (two- or three dimensional, simple or complex) (2nd research objective).

Finally, the discussion of the paper is focused: a. on the influence that previous visual experience of individuals with visual impairments may result in choosing the type of conceptual reference system, and b. on the educational implications of the results.

Keywords:

Conceptual reference systems, visual impairment, active exploration, shapes.