Semiautomatic Tracking of Neuronal Processes

As the morphological sciences become more quantitative and experimental, and as more subtle phenomena are explored, the development of appropriate tools becomes important to the production of quantitative data in volume. The need for quantitative morphological data has long been recognized, and quantitative study of the nervous system was emphasized over 50 years ago by S. T. Bok, whose early work is represented in a more recent volume (Bok, 1959) and developed further by Sholl (1956) in studies of the nervous system, especially dendrites. These early efforts were, however, hampered by the lack of appropriate tools and the tedious nature of the manual data-collection procedures. As a result, many early studies dealt with relatively small numbers of measures. Some consequences of this limited data base include statistical imprecision and erroneous conclusions. As a step toward overcoming these limitations, the need for automated techniques in the morphological sciences was coupled to developing electronic technology over 20 years ago by J. Z. Young in his work with Causley on the flying-spot scanner (Causley and Young, 1955). Other early flying-spot scanners and related devices were described by Friesen (1965), Lorch (1967), Mansberg and Segarra (1962), Tolles and Mansberg (1962), Kirsch et al (1957), Ledley (1964), and others. More recent dendrite measurement equipment has been described by Wann et al. (1973), Lindsay (1971), and Garvey et al (1972,1973).