Self-organisation can generate the discontinuities in the somatosensory map
نویسندگان
چکیده
The primary somatosensory cortex contains a topographic map of the body surface, with two notable discontinuities—the representation of the face is next to that of the hands, and that of the feet is next to the genitals. Farah [Why does the somatosensory homunculus have hands next to face and feet next to genitals? a hypothesis. Neural Computation 10(8) (1998) 1983–1985] has suggested that these discontinuities are due to the mechanisms of self-organisation which underlie cortical map development. The typical position of the foetus in the womb means that these two pairs of body parts will often touch and hence their representations will be simultaneously co-active, even though they are distal in terms of the body surface. We use the Kohonen self-organising map algorithm to provide an existence proof of the plausibility of Farah’s hypotheses. We then use the model to test the viability of other possible causes of the known map structure and to explore the limitations of self-organisation for explaining the features of the somatosensory map. The model shows that (a) the Kohonen algorithm requires high frequencies of co-activation to introduce a selective discontinuity into the map, and (b) that higher frequency of separate activation of the critical patterns alone is not sufficient to generate the selective discontinuity and (c) the consistency of near-optimal map formation, and in particular the medial–lateral ordering, cannot be reliably generated by a simple Kohonen algorithm. r 2006 Elsevier B.V. All rights reserved.
منابع مشابه
Submission to neurocomputing 1 Self - organisation can generate the discontinuities in the somatosensory map
The primary somatosensory cortex contains a topographic map of the body surface, with two notable discontinuities — the representation of the face is next to that of the hands, and that of the feet is next to the genitals. Farah (1998) has suggested that these discontinuities are due to the mechanisms of self-organisation which underlie cortical map development. The typical position of the foet...
متن کاملClassification of Streaming Fuzzy DEA Using Self-Organizing Map
The classification of fuzzy data is considered as the most challenging areas of data analysis and the complexity of the procedures has been obstacle to the development of new methods for fuzzy data analysis. However, there are significant advances in modeling systems in which fuzzy data are available in the field of mathematical programming. In order to exploit the results of the researches on ...
متن کاملTHE APPLICATION OF DATA ENVELOPMENT ANALYSIS METHODOLOGY TO IMPROVE THE BENCHMARKING PROCESS IN THE EFQM BUSINESS MODEL (CASE STUDY: AUTOMOTIVE INDUSTRY OF IRAN)
This paper reports a survey and case study research outcomes on the application of Data Envelopment Analysis (DEA) to the ranking method of European Foundation for Quality Management (EFQM) Business Excellence Model in Iran’s Automotive Industry and improving benchmarking process after assessment. Following the global trend, the Iranian industry leaders have introduced the EFQM practice to thei...
متن کاملGait Based Vertical Ground Reaction Force Analysis for Parkinson’s Disease Diagnosis Using Self Organizing Map
The aim of this work is to use Self Organizing Map (SOM) for clustering of locomotion kinetic characteristics in normal and Parkinson’s disease. The classification and analysis of the kinematic characteristics of human locomotion has been greatly increased by the use of artificial neural networks in recent years. The proposed methodology aims at overcoming the constraints of traditional analysi...
متن کاملVestibular contribution to self - awareness
Information from the vestibular peripheral organs in the inner ear is integrated with several other classes of signals about the body, generated by eyes, muscles and joints. The resulting signals provide a coherent sense of body posture and orientation in surrounding space. In this project, the vestibular organs of healthy volunteers were stimulated noninvasively. Participants made judgements a...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Neurocomputing
دوره 70 شماره
صفحات -
تاریخ انتشار 2007