Ideas about sensory perception - an interdisciplinary project within the framework of the Didactic Reconstruction model

Theory

Physical explanations of physiological processes of sensory perception offer opportunities to overcome restrictions to individual school subjects and to embed content in contexts relevant to everyday life and science. By embedding the laws of physics in biological contexts, one of the main problems, the lack of interest in this subject among pupils (Hoffmann, L. et al.; 1998), can be countered. With this aim in mind, the Didactic Reconstruction (Duit et. al.; 2005) collects and analyses students' perceptions in the field of "sensory perception" in order to relate them to the perceptions of scientists (present and past centuries). The model is based on a moderate constructivist learning theory (Duit; 1995), in which learners link new knowledge to existing knowledge, with the consequence that teachers must orientate lessons to the level of knowledge of the students. Teaching guidelines for interdisciplinary teaching are drawn up by taking a reciprocal view of the student and subject perspectives.

Research question

What ideas do pupils and academics have about sensory perception? The term "sensory perception" is divided into: Process, organs and places of sensory perception, learning from and objectifiability of sensory perception.

Methods

20 interviews with eleventh-graders were conducted in order to ascertain students' perceptions. In the specialised field of physiology textbooks and historical sources (Boerhaave, Galvani, Volta and v. Helmholtz) are analysed. The data from both sides will be analysed using the qualitative content analysis method (Mayring; 2002) and categorised using a computer.

Results

In the section on the structure and function of the nerve, one pupil responded to the question of how he imagines a nerve: The nerve is something like a telephone line. It consists of a receiver under the skin, the cable; the brain is the telephone exchange. With regard to the speed of information transmission, the question was asked how long it takes for a tactile stimulus to reach the brain. The answer was as follows: 1) This can be measured with very fast measuring devices. If you measure the difference between tapping and twitching with a camera and how long the distance is, you can find out. 2) The speed at which information is sent through the body cannot be measured. If you touch something, you know it immediately.

Conclusions

Different conclusions can be drawn from the student interviews and specialised literature analysed so far. For example, it can be concluded from the mutual comparison that the use of analogies with regard to the "telephone line metaphor" can be fruitful in learning situations. Here, the specialised scientific concept "neuron" can be seen as analogous to the student's concept.

Conception of sensory perception - A multidisciplinary project in the framework of the Model of Educational Reconstruction

Theory

"If you press skin on nerves when you touch a desk with a finger a little yellow electric pulse will be conducted to the brain." This statement from a 16 years old German grammar school student shows that even for students the area of "neuronal science" and espe-cially "the conduction of information" includes several physic processes ("little yellow elec-tric pulse") and allows for encasing physical contents into biology lessons. If by this phys-ics is embedded in biology classrooms there is a great chance to remove one of the main problems of the subject of physics: the weak interest of students in this discipline (Hoff-mann, et al. 1998). This research aims at creating an interdisciplinary teaching unit about neuronal sciences based on students' and former/present scientist' conceptions. The investigation is embed-ded into the Model of Educational Reconstruction (Duit, et al; 2005) which helps to com-pare students' and scientists' conceptions in a reflected theoretical process. The Model is based on a constructivist theory of learning (Duit, 1995). In this theory learning is regarded as an active, multidimensional construction process that is based on prior knowledge and everyday conceptions.

Research question

Which conceptions do students and scientists (former and present) hold about sensory perception? The concept sensory perception is split up into: process, organs and locations of sensory perception, learning & experiences deriving from sensory perceptions.

Method

Several students' statements like the one stated above are investigated in an interview-study with 20 students from German grammar school. The qualitative method by P. May-ring (2003) qualitative content analysis is applied to investigate conceptions of students and scientists of sensory perception. In the case of the students' conceptions the tran-scriptions of the interviews are evaluated using computer-assisted content analysis with Atlas.ti™.

Results and Conclusion

Different concepts which have been assigned to different categories used in the interview guide have been identified: e.g. the concepts of the students in the area of the conduction of information reach very different grades of elaboration. One student describes this proc-ess only with the metaphor of a telephone wire and is not able to explain the biological structure or the physiological process any further. Another student points out that nerves are living cells, the transmitted electrical signals within the human body are encoded in an electric way, and there is a little lightning saltation between the nerves. These two students' statements are only a selection in the range of answers given about the conduction of information. The statements show that the students' hold very different conceptions but we can also recognise some metaphors which are used from several. The results of the analysis of four important scientists' ideas in the field of "conduction of information" (Boerhaave, Galvani, Volta and v. Helmholtz) and the comparison of these ideas with students conceptions are the recognition of several tools for taking these con-cepts into teaching lessons. As a main tool the analogy which is used from different scien-tists to explain the "conduction of information" should be mentioned.

• Sundermeier, S. & Rieß, F. (2007): Ideas about sensory perception. Didactic reconstruction in an interdisciplinary project. In: D. Höttecke (ed.): Naturwissen-schaftlicher Unterricht im internationalen Vergleich, GDCP Jahrestagung 2006. vol. 27.Münster [u.a.]: LIT Verlag.
• Sundermeier, S. (2006): "What pupils think about blood." Interviews and professional perceptions of a human biological term. Oldenburger Vor-Drucke 540. University of Oldenburg, Centre for Pedagogical Professional Practice.
• Sundermeier, S. (2004): Pupils' conceptions of blood in the human body - results of an empirical study of pupils' conceptions - a contribution to dia-dactic reconstruction. Seminar paper as part of the first state examination for the teaching profession at grammar schools. University of Hanover (unpublished).

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