- Email: [email protected]
Brain Browser™: a Hypercard® Application for the Macintosh®
books that makes the work of the most diligent authors appear out of date compared with that of the slower authors. In this case, though, these discrepancies are a small price to pay for an otherwise superb introduction to this field. The second part of the book, although not comprehensive, is excellent. Two of the five chapters relate to the gut functions, motility and secretion, one deals with the cardiovascular system, and the remaining two attempt to give an overall perspective of how investigators should regard regulatory peptides. Both authors of these last two chapters, the first on co-existence and co-function, the second on biosynthesis of peptides, consider what evolutionary pressures might have been involved in the preservation
of so many families of peptides across the zoological scale. This is a difficult task in that the physiological roles of only few peptides, in some specific functions in some species are known. This book highlights how little is known about the specific physiological roles of diverse peptides, for different functions, in different species. The reviews concentrate on the extensive work on the identification of peptides, their localization in different animals, organs, tissues and cells, their metabolism, their effect and mechanism of action on every tissue and cell type. Also, some inappropriate extrapolations are made from the demonstration of the presence of a peptide, and the observation that it acts on a variety of tissues to the conclusion that the physiological function
has been established. However, in many cases the authors end with a more guarded conclusion about the postulated role of a particular peptide in a certain function. An even more cautious conclusion is expressed by Michael Thorndyke in chapter 9 that 'indeed the mere presence (and I would add actions) of a peptide in a neurone (or any other cell) does not prove function and clearly careful physiological experiment must be used to justify transmitter or modulatory function'. This should be seen not as an insurmountable obstacle but as an encouragement to investigate the physiological roles of regulatory peptides wherever they are found in the justified assumption, from the evolutionary perspective, that they do have a physiological role.
Brain BrowserTM: a Hypercard ® Application for the Macintosh ®
those whose everyday benchwork involves the rat brain. Brain nuclei and tracts can be rapidly searched for by word or by image and located on brain sections in a digital version of The Rat Brain in Stereotaxic Coordinates (George Paxinos and Charles Watson, Academic Press, 1986). This itself has no advantages over a quick leaf through Paxinos and Watson's book (which is more useful in many ways because of its large clear diagrams and corresponding excellent quality micrographs on the printed page) but what the Brain Browser can then offer is something that the pages of the hardcopy cannot. Once a particular brain area has been located on the simplified brain section drawings a whole array of information regarding this particular area lies only a click of the mouse away. Information on afferent and efferent circuitry, cell types, neurotransmitters, receptors, second messengers, systems, topography, collaterals, ion channels and even cell birth dates can be brought to life. Another click and bibliographic references, including an abstract, key words and comments that describe these data can be brought to the screen. Unfortunately, the amount of data that is already in the package
in this way is small and oddly enough, as the authors say, it is not fully defined. It is not inaccurate, just incomplete. The retina, for example, is not listed as an afferent source for the dorsal lateral geniculate nucleus. Therefore, this package as it is purchased is not intended to be a complete reference source but a database upon which the operator builds. In this respect Brain Browser could allow a researcher to compile a large and useful and comprehensive database of brain structures and circuits of personal interest that could be updated rapidly. Coordinates of nuclei positions can be read as they can from the atlas hardcopy but in addition there are possibilities for reproducing a printed copy of a brain section with user-added shading or neurone icons to represent axonal terminal labelling and retrogradely labelled neurones, respectively. Unfortunately, the drawings are rather poor and even on printouts the curves have a jerky course and are not smooth. In addition, measurements of length and area can be made of brain structures. Like most computer software this package requires considerable time and effort to get accustomed to and will probably be of
by Floyd E. Bloom, Warren G. Young and Yung M. Kim, Academic Press, 1990. $295.00 (six computer disks and manual of 220 pages) ISBN 0 12 107250 9
This is an impressive first attempt, as far as I know, by anyone to create computer software designed to teach and catalogue the nuts and bolts of the brain. Essentially, what the authors have produced is a way of viewing and creating a database of brain structures and circuits that can actually be fun. It sets out to be a teacher, a digital stereotaxic atlas and a comprehensive database. The teacher section, where it is perhaps weakest, is aimed primarily at beginners in the field of neuroscience and would, for example, greatly benefit those biologists about to embark on a molecular quest of the brain. For those with a greater knowledge of neuroanatomy but who want to look up quickly the constituent parts of the thalamus, for example, it is also useful. However, apart from an accurate and organised catalogue of brain structures the emphasis is on transmitters. But the package is really of most use to TINS, Vol. 13, No. 12, 1990
Greg Campbell Departmentof Anatomyand Developmental Biolo~, University CollegeLondon, WindeyerBuilding, ClevelandStreet, LondonWlP6DB,UK.
507
Karen K. De Valois
PhysiologicalOptics andPsycholog7 Department, Universityof Californiaat Berkeley, Berkeley,CA94720, USA.
508
greatest appeal to Macintosh aficionados. Even with the relatively user-friendly Macintosh computer and the very comprehensive Help stacks the software can be a bit daunting and cumbersome. However, apart from a few faults such as a rather poor dictionary, the lack of both keyboard shortcuts and a troubleshooting guide the authors and programmers have produced a
worthy database, linked to a stereotaxic atlas that can be used by students and researchers alike. The package is reasonably priced but the hardware necessary to run it, which must include a considerable amount of memory, is expensive, especially in Europe. It is likely to be a hit in neuroscience labs and departments that are already sharing a system of Macintosh computers like some
groups in the USA but elsewhere it may only find an audience among the select few who can afford the hardware. I congratulate the authors on this first attempt and encourage them, and others, to amend, simplify and update the database and to explore other areas of neuroscience where similar software and databases could be both useful and fun.
Visual Pattern Analyzers (Oxford Psychology Series, No. 16)
an enormous amount of the relevant psychophysical literature from scores of laboratories. Her focus is less on the character of the analysers themselves than on the logic of the experimentation that has been used to reveal them. The emphasis on methodology and modeling rather than on results is unusual and might make this a different book for beginners. However, the methodological emphasis may be the book's most significant contribution, because in the excitement of discovery, the pale rigors of design and logic are often ignored. Graham has carefully evaluated the evidence for multiple, selective analysers operating on nearthreshold patterns along each of 17 dimensions. The choice of dimensions is somewhat unusual, including, for example, eye-oforigin but not selectivity for color variation or depth. The author says she has restricted her consideration to studies using nearthreshold stimuli because of difficulties in interpretation and a lack of replicability of studies on suprathreshold stimuli. This restriction is a significant limitation. Suprathreshold masking experiments, for example, are eliminated, although subthreshold summation experiments- which are virtually identical in design - are discussed. Yet it is just those suprathreshold studies, which have provided interesting and significant information about visual pattern analysers, that would benefit most from the careful kind of critique provided here for other experimental paradigms. The bulk of Graham's book is organized with respect to four psychophysical paradigms (pattern adaptation experiments,
summation experiments, experiments evaluating uncertainty models, and identification experiments) and the models that have been developed to account for the resulting data. Although there are frequent references to and limited discussion of specific experiments, most of the discussion (indeed, half of the volume) concerns the logic of experimentation, the kinds of outcomes one might expect, and the conclusions and models that can reasonably be based upon them. This rigorous logical and methodological analysis will surely outlast the specific conclusions with respect to facts, which will doubtless change with time and more data; Graham's emphasis on the logic of experimentation and modeling in general, and her explicit delineation of the often unrecognized assumptions underlying those widely used psychophysical paradigms will remain a rich lode. Visual Pattern Analyzers will serve different functions for two separate audiences. For the cognoscenti of pattern vision, it provides an excellent reference source to a large and complex literature, with an organized and annotated bibliography of nearly 1200 citations, an index of assumptions, and a lucid treatment of much of the relevant mathematical background. For students of sensory systems in general (and this includes those of many years' experience as well as neophytes), it offers a careful, thorough and accessible source of information about how to design and interpret experiments and construct models without falling prey to ever-present logical pitfalls. The former is useful, but the latter is a lasting service.
by Norma Van Surdam Graham, Oxford University Press, 1989. £65.00 (xvi + 646 pages) ISBN 0 19 505154 8
It is generally argued that visual perception is based upon an initial decomposition of the visual image, followed by a resynthesis in which the ultimate product is not identical to the original scene. The past three decades have produced an explosion of information about the early analytic processes, based in large part upon the creative work of John Robson and Fergus Campbell at Cambridge University, UK, who suggested that the early visual system could be considered as a set of quasi-linear, spatial frequency-tuned filters operating in parallel on the retinal image. Knowing the characteristics of the filters should allow one to predict the detectability of any pattern and the extent to which it can be discriminated from any other. This insightful suggestion simultaneously provided a new set of questions to explore and the analytic tools with which to do so. The pursuit of the filters (or in Graham's terms, analysers) was on. Psychophysicists and physiologists worked in parallel to determine the dimensions along which visual mechanisms are selective, and the limits of such selectivity. It is this early analytic level with which Graham's book is concerned. She has made important contributions to the study of visual pattern analysers, and she here provides another signal service by compiling and reviewing
TINS, VoL 13, No. 12, 1990
of so many families of peptides across the zoological scale. This is a difficult task in that the physiological roles of only few peptides, in some specific functions in some species are known. This book highlights how little is known about the specific physiological roles of diverse peptides, for different functions, in different species. The reviews concentrate on the extensive work on the identification of peptides, their localization in different animals, organs, tissues and cells, their metabolism, their effect and mechanism of action on every tissue and cell type. Also, some inappropriate extrapolations are made from the demonstration of the presence of a peptide, and the observation that it acts on a variety of tissues to the conclusion that the physiological function
has been established. However, in many cases the authors end with a more guarded conclusion about the postulated role of a particular peptide in a certain function. An even more cautious conclusion is expressed by Michael Thorndyke in chapter 9 that 'indeed the mere presence (and I would add actions) of a peptide in a neurone (or any other cell) does not prove function and clearly careful physiological experiment must be used to justify transmitter or modulatory function'. This should be seen not as an insurmountable obstacle but as an encouragement to investigate the physiological roles of regulatory peptides wherever they are found in the justified assumption, from the evolutionary perspective, that they do have a physiological role.
Brain BrowserTM: a Hypercard ® Application for the Macintosh ®
those whose everyday benchwork involves the rat brain. Brain nuclei and tracts can be rapidly searched for by word or by image and located on brain sections in a digital version of The Rat Brain in Stereotaxic Coordinates (George Paxinos and Charles Watson, Academic Press, 1986). This itself has no advantages over a quick leaf through Paxinos and Watson's book (which is more useful in many ways because of its large clear diagrams and corresponding excellent quality micrographs on the printed page) but what the Brain Browser can then offer is something that the pages of the hardcopy cannot. Once a particular brain area has been located on the simplified brain section drawings a whole array of information regarding this particular area lies only a click of the mouse away. Information on afferent and efferent circuitry, cell types, neurotransmitters, receptors, second messengers, systems, topography, collaterals, ion channels and even cell birth dates can be brought to life. Another click and bibliographic references, including an abstract, key words and comments that describe these data can be brought to the screen. Unfortunately, the amount of data that is already in the package
in this way is small and oddly enough, as the authors say, it is not fully defined. It is not inaccurate, just incomplete. The retina, for example, is not listed as an afferent source for the dorsal lateral geniculate nucleus. Therefore, this package as it is purchased is not intended to be a complete reference source but a database upon which the operator builds. In this respect Brain Browser could allow a researcher to compile a large and useful and comprehensive database of brain structures and circuits of personal interest that could be updated rapidly. Coordinates of nuclei positions can be read as they can from the atlas hardcopy but in addition there are possibilities for reproducing a printed copy of a brain section with user-added shading or neurone icons to represent axonal terminal labelling and retrogradely labelled neurones, respectively. Unfortunately, the drawings are rather poor and even on printouts the curves have a jerky course and are not smooth. In addition, measurements of length and area can be made of brain structures. Like most computer software this package requires considerable time and effort to get accustomed to and will probably be of
by Floyd E. Bloom, Warren G. Young and Yung M. Kim, Academic Press, 1990. $295.00 (six computer disks and manual of 220 pages) ISBN 0 12 107250 9
This is an impressive first attempt, as far as I know, by anyone to create computer software designed to teach and catalogue the nuts and bolts of the brain. Essentially, what the authors have produced is a way of viewing and creating a database of brain structures and circuits that can actually be fun. It sets out to be a teacher, a digital stereotaxic atlas and a comprehensive database. The teacher section, where it is perhaps weakest, is aimed primarily at beginners in the field of neuroscience and would, for example, greatly benefit those biologists about to embark on a molecular quest of the brain. For those with a greater knowledge of neuroanatomy but who want to look up quickly the constituent parts of the thalamus, for example, it is also useful. However, apart from an accurate and organised catalogue of brain structures the emphasis is on transmitters. But the package is really of most use to TINS, Vol. 13, No. 12, 1990
Greg Campbell Departmentof Anatomyand Developmental Biolo~, University CollegeLondon, WindeyerBuilding, ClevelandStreet, LondonWlP6DB,UK.
507
Karen K. De Valois
PhysiologicalOptics andPsycholog7 Department, Universityof Californiaat Berkeley, Berkeley,CA94720, USA.
508
greatest appeal to Macintosh aficionados. Even with the relatively user-friendly Macintosh computer and the very comprehensive Help stacks the software can be a bit daunting and cumbersome. However, apart from a few faults such as a rather poor dictionary, the lack of both keyboard shortcuts and a troubleshooting guide the authors and programmers have produced a
worthy database, linked to a stereotaxic atlas that can be used by students and researchers alike. The package is reasonably priced but the hardware necessary to run it, which must include a considerable amount of memory, is expensive, especially in Europe. It is likely to be a hit in neuroscience labs and departments that are already sharing a system of Macintosh computers like some
groups in the USA but elsewhere it may only find an audience among the select few who can afford the hardware. I congratulate the authors on this first attempt and encourage them, and others, to amend, simplify and update the database and to explore other areas of neuroscience where similar software and databases could be both useful and fun.
Visual Pattern Analyzers (Oxford Psychology Series, No. 16)
an enormous amount of the relevant psychophysical literature from scores of laboratories. Her focus is less on the character of the analysers themselves than on the logic of the experimentation that has been used to reveal them. The emphasis on methodology and modeling rather than on results is unusual and might make this a different book for beginners. However, the methodological emphasis may be the book's most significant contribution, because in the excitement of discovery, the pale rigors of design and logic are often ignored. Graham has carefully evaluated the evidence for multiple, selective analysers operating on nearthreshold patterns along each of 17 dimensions. The choice of dimensions is somewhat unusual, including, for example, eye-oforigin but not selectivity for color variation or depth. The author says she has restricted her consideration to studies using nearthreshold stimuli because of difficulties in interpretation and a lack of replicability of studies on suprathreshold stimuli. This restriction is a significant limitation. Suprathreshold masking experiments, for example, are eliminated, although subthreshold summation experiments- which are virtually identical in design - are discussed. Yet it is just those suprathreshold studies, which have provided interesting and significant information about visual pattern analysers, that would benefit most from the careful kind of critique provided here for other experimental paradigms. The bulk of Graham's book is organized with respect to four psychophysical paradigms (pattern adaptation experiments,
summation experiments, experiments evaluating uncertainty models, and identification experiments) and the models that have been developed to account for the resulting data. Although there are frequent references to and limited discussion of specific experiments, most of the discussion (indeed, half of the volume) concerns the logic of experimentation, the kinds of outcomes one might expect, and the conclusions and models that can reasonably be based upon them. This rigorous logical and methodological analysis will surely outlast the specific conclusions with respect to facts, which will doubtless change with time and more data; Graham's emphasis on the logic of experimentation and modeling in general, and her explicit delineation of the often unrecognized assumptions underlying those widely used psychophysical paradigms will remain a rich lode. Visual Pattern Analyzers will serve different functions for two separate audiences. For the cognoscenti of pattern vision, it provides an excellent reference source to a large and complex literature, with an organized and annotated bibliography of nearly 1200 citations, an index of assumptions, and a lucid treatment of much of the relevant mathematical background. For students of sensory systems in general (and this includes those of many years' experience as well as neophytes), it offers a careful, thorough and accessible source of information about how to design and interpret experiments and construct models without falling prey to ever-present logical pitfalls. The former is useful, but the latter is a lasting service.
by Norma Van Surdam Graham, Oxford University Press, 1989. £65.00 (xvi + 646 pages) ISBN 0 19 505154 8
It is generally argued that visual perception is based upon an initial decomposition of the visual image, followed by a resynthesis in which the ultimate product is not identical to the original scene. The past three decades have produced an explosion of information about the early analytic processes, based in large part upon the creative work of John Robson and Fergus Campbell at Cambridge University, UK, who suggested that the early visual system could be considered as a set of quasi-linear, spatial frequency-tuned filters operating in parallel on the retinal image. Knowing the characteristics of the filters should allow one to predict the detectability of any pattern and the extent to which it can be discriminated from any other. This insightful suggestion simultaneously provided a new set of questions to explore and the analytic tools with which to do so. The pursuit of the filters (or in Graham's terms, analysers) was on. Psychophysicists and physiologists worked in parallel to determine the dimensions along which visual mechanisms are selective, and the limits of such selectivity. It is this early analytic level with which Graham's book is concerned. She has made important contributions to the study of visual pattern analysers, and she here provides another signal service by compiling and reviewing
TINS, VoL 13, No. 12, 1990