Man/machine interaction in adaptively controlled experimental conditions

Systems in which a human subject interacts with an adaptive control mechanism through display and response facilities are examined. A cybernetic model is discussed, together with supporting experimental data. The research reported in this paper has been supported by the Air Force Office of Scientific Research, under Contract AF. 61.052.640. (for Cybernetic models for learning) and by the Aerospace Medical Research Laboratories A.F.C.S., under contract AF. 61.052.402. (for adaptive teaching systems), through the European Office for Aerospace Research.     

Electroencephalographic evidence of “Gestalt” in the perception of movement by the frog

Summary Some records, obtained from the surface of the optic tectum of the frog with moving visual stimuli are presented as evidence of a global oscillation of the tectal activity whose time course is specific for different patterns of stimulation.The research reported in this document has been sponsored by the 6570th Aerospace Medical Research Laboratory under grant AF EOAR 65-44 through the European Office of Aerospace Research (OAR), United States Air Force.     

Spectral absorption by screening pigment granules in the compound eyes of a moth and a wasp

Summary The spectral absorption by single ommin containing pigment granules or clusters of granules from compound eyes was measured spectrophotometrically between 300 and 700 nm. The measurements were made on fresh and fixed slices from compound eyes of Celerio euphorbiae and Vespa spec. In the visible part of the spectrum there is an absorption maximum between 540 and 550 nm, situated nearly 30 nm more towards the red than that of pure ommin in solution. A frequently found side maximum of variable height at about 450 nm is probably caused by oxidized xanthommatin occurring additionally within the granules. The absorption increases from 350 nm towards shorter wavelengths, and gradually declines between 550 and 700 nm.This work was supported partly by the Swedish Medical Research Council, Stiftelsen Gustaf och Tyra Svenssons Minne, Reservationsanslaget, and partly by the Air Force Office of Scientific Research through the European Office of Aerospace Research, OAR, United States Air Force under grant number EOOAR-68-0036.     

Decision equation for binary systems. Application to neuronal behavior

Summary The exact mathematical treatment is given for a non linear equation describing the delayed yes-or-no response to a binary system to external stimulations, in some typical cases of interest. Comparison is made with neurophysiological data on the frequency rate of firings of stimulated neurons; the same equation, however, can be conceivably applied to a vast variety of phenomena. The procedures followed to solve the problems that arise in connection with this equation could be extended to more general types of non linear equations.The research reported in this document has been sponsored in part by the Air Force Office of Scientific Research under Contract no. AF EOAR 65-44 through the European Office of Aerospace Research, OAR, United States Air Force.     

On the interpretation of the effect of area on the critical flicker frequency

The effects of area and intensity on the critical flicker frequency, threshold, and reaction time are considered in terms of neural net theory. An attempt is made to develop a mechanism which can account for the phenomena associated with the empirically observed laws of Ricco, Granit, Talbot, and Ferry-Porter as well as observations on reaction time and threshold. A simple model gives results which are substantially in agreement with observation except for a few apparent discrepancies. Experimental procedures are suggested which can determine whether these are apparent or real. This research was supported by the United States Air Force through the Air Force Office of Scientific Research of the Air Research and Development Command under contract No. AF 18(600)-1454. Reproduction in whole or in part is permitted for any purpose of the United States Government.     

Human eye tracking as a sequential input adaptive process

Sequential input adaptive system theory is applied to human eye tracking of targets with one-dimensional dimensional motion defined by sine functions, sums of sine functions and triangle functions. The sequential theory describes the mean eye tracking movements of two subjects for these inputs. The theory is predictive for irregular inputs in that when its parameters for a subject are identified and adjusted for a reference input, it then predicts mean eye tracking behavior for that subject for inputs of comparable complexity.This research was initiated while D. E. Greene was at the Biodynamics and Bioengineering Division, Aerospace Medical Research Laboratory, Wright-Patterson Air Force Base, Dayton, Ohio     

A model for conditioning and the effect of spaced trials in learning

A mechanism is suggested in which a postulated substance can enter a synaptic region only during the simultaneous action of a conditioned and an unconditioned stimulus. If this substance remains and produces a physico-chemical change, then a consequence is that the degree of learning will depend on the spacing of conditioning trials and the time constant of the process will be related to the rate of diffusion or transport of the substance along the axon. This research was supported by the United States Air Force through the Air Force Office of Scientific Research of the Air Research Development Command under Contract No. AF 49(638)-414.     

Growth responses of barley seedling to simulated weightlessness induced by two-axis rotation

Summary A device used for simulated weightless studies is described and is called the Nogravatron. The Nogravatron apparatus produces simulated weight-lessness by rotating seedlings simultaneously at the rate of 0.25 rpm and 1.0 rpm in two axes perpendicular to each other. Atlas barley seedlings grown on the apparatus grew at rates different from that of stationary controls. Coleoptile elongation in rotated barley was not inhibited by light during the first 55 hours of rotation treatment whereas stationary controls were photoinhibited. After 55 hours the growth of rotated coleoptiles was inhibited by light. The coleoptiles did not show movements and were oriented along the longitudinal axis of the seed. Roots also did not show geotropic movements but the growth direction was affected by the proximity of other roots. Coleoptiles rotated in dark were significantly longer than stationary controls on the third and fourth day but not so on the fifth day and later. Coleoptiles rotated in light were about 35 percent longer than the stationary coleoptiles by the third day and maintained this significant difference to the end of the experiment.Supported in part by NASA Grant NsG 538-63 and by Air Force Office of Scientific Research Office of Aerospace Research, United States Air Force, Contract No. AF 49 (638)-1387.     

Representation of modality in cutaneous sensibility

Morphologically identical nerve endings subserve more than one sensory modality. Two possible explanations are: such endings are functionally different, responding to one type of physical excitation only, or such endings are capable of responding to more than one type of physical stimulus, but central mechanisms discriminate between different stimuli. A simple network is described to illustrate how thermal receptors could discriminate between thermal and mechanical stimuli. This research was supported in part by the United States Air Force Office of Scientific Research of the Air Research and Development Command under contract No. AF 18(600)-1454. Reproduction in whole or in part is permitted for any purpose of the United States Government.     

A stereologic electron microscope study of “tubular myelin figures” in alveolar fluids of rat lungs

Summary The three-dimensional structure of a composite material found in alveolar exudate of oxygen poisoned lungs but also present in normal lungs is stereologically analysed. It is composed of tubules of 450 Å diameter which are tightly packed in a quadratic lattice. The wall of the tub vile is formed by four-winged osmiophilic filaments which are located in the corners of the quadratic lattice; their interior is made up of a hydrophilic substance which contains either a tubule or a filament of moderate electron density. The osmiophilic substance of the walls is continuous with associated myelin figures which can be resolved into lamellae with a periodicity of 42 Å and can thus be considered to be water crystals of phospholipids. The nature of the content of the tubules, which presumably exerts the formative force on the phospholipid lamellae to form tubules, remains undetermined.Dedicated to Prof. W. Bargmann in honor of his 60th birthday.The research reported here has been sponsored by the Schweizerischer Nationalfonds zur Förderung der wissenschaftlichen Forschung (Nr. 2569); by the Stiftung für wissenschaftliche Forschung an der Universität Zürich; by the National Institutes of Health, USPHS, through grant RF-57; and the 6570th Aerospace Medical Research Laboratories under contract AF 61(052)-784 through the European Office of Aerospace Research (OAR), United States Air Force.     

A program for the study of long-term adaptation to a weightless environment providing three-dimensional freedom of movement

The mechanical details of a working model of a proposed small-animal space station which is currently undergoing bench tests are briefly described together with supporting evidence pointing to the feasibility of the program. The one-third cubic meter canister weighs less than 250 kg when loaded for a 9-month period. It would transmit by slow-scan television data concerning mice which it is proposed would be born in the weightless state. Observation of their silhouettes would indicate their growth rates and study of the picture sequence their activity patterns. For example, their use and defense of the feeding and nesting areas and their care of their young.The device would also be used to determine whether the weightless state affected the development of a circadian rhythm or the periodicity of any rhythm that was observed. Recovery of the animals' special living compartment by rendezvous in orbit would permit testing of those born in the device in the earth's gravity field by familiar methods such as those that have been used for the assessment of negative geotactic responses and for the evaluation of rodents living in vertical, as opposed to horizontal mazes.This work was jointly supported by the National Aeronautics and Space Administration, Office of Advanced Research and Technology, and the United States Air Force's Aerospace Medical Division through United States Air Force Contract F29600-67-C-0010.     

Electron microscopic observations on the reactional changes occurring in insect nerve fibers after transection

Summary An electron microscopic study of the interganglionic connectives of an orthopteran (Laplatacris dispar) demonstrated that a reaction starts in the sectioned fibers very soon after transection (30 minutes). This reaction is closely similar to that observed in sectioned nerves of vertebrates and consists in the appearance of microvesicles and the proliferation of mitochondria. Sectioned connectives were studied from 30 minutes to 88 hours after section. The reaction mentioned increases progressively during the indicated lapse of time.This research was supported by the United States Air Force under Contract No AF 49 (638) 585 and Grant Af 61-64, monitored by the Air Force Office of Scientific Research, Air Force Research Division of the Air Research and Development Command.     

Stability and looping in connectionist models with asymmetric weights

Recently, researchers in artificial intelligence have been actively investigating various connectionist models of computation. The model that is often studied is that of an asynchronous symmetric network, in which a global energy measure can be established and used to prove that the network totally stabilizes. In this paper, we discuss asymmetric networks that might admit infinite activated computations. Within this framework, we define an operational semantics under a synchronous activation rule and similarly under a fair asynchronous rule. Using this semantics, we analyze flow properties of a circle-network with respect to a specification that characterizes oscillation. We further explore the complexity of the decidable question of whether or not a given asymmetric network totally stabilizes. It is shown that this problem is NP-hard, and is in PSPACE.We thank the Xerox Corporation University Grants Program for providing equipment used in the preparation of this paper. This work was supported by the Air Force Systems Command, Rome Air Development Center, Griffiss Air Force Base, New York 13441-5700, and the Air Force Office of Scientific Research, Boiling AFB, DC 20332 under Contract No. F30602-85-C-0008. This contract supports the Northeast Artificial Intelligence Consortium (NAIC). A preliminary version of this paper was presented at the Ninth European Meeting on Cybernetics and Systems Research, Vienna, Austria, April, 1988     

Contributions to the theory of active transport: II. The gate type non-carrier mechanism and generalizations concerning tracer flow,efficiency, and measurement of energy expenditure

The gate type non-carrier mechanism, an active transport model, is discussed. In this mechanism, the actively transported particle passes through the gate itself by means of a series of reorganizations of the active transport mechanism. The net rate of transport, the rate of transport in either direction, and the efficiency of this model are analyzed. It is shown that on the basis of these analyses alone, this mechanism cannot be distinguished from a carrier mechanism. Three generalizations which apply to many individual type active transport models are then discussed. These pertain to (1) the dependency of the flow in one direction on the cencentration of the particles on the opposite side of the membrane, (2) the possibility of very high efficiencies for these models independent of the rate of the active transport, and (3) the methods whereby the energy expended in the active transport may be experimentally found. This research was supported by the United States Air Force through the Air Force Office of Scientific Research of the Air Research and Development Command under contract No. AF 18(600)-1454. Reproduction in whole or in part is permitted for any purpose of the United States Government.     

Remarkable adrenergic nerves in the exocrine pancreas

Summary The adrenergic nerves in the pancreas of mice, rats, guinea-pigs, rabbits, and cats were investigated with the fluorescence method of Falck and Hillarp. The relations between the adrenergic fibres and the vessels were studied by the injection of india ink into the vessels.Besides the normal manifestation of adrenergic fibres at the large vessels, some vessels of capillary size were also accompanied by adrenergic fibres. These fibres had a very weak fluorescence, and showed up regularly only when the animal had been treated with Nialamide and L-DOPA or dopamine to increase the catecholamine content of the adrenergic fibres. The weakness of the fluorescence is perhaps due to low transmitter concentration or to small size of the nerve fibres, or to both. A rough estimate indicated that either the transmitter concentration of the nerve fibre is at least approximately 100 times below that seen in adrenergic nerves in other tissues, or that the radius of the varicosities of the nerve fibres is less than 0.2 . Neither alternative has previously been recognized.The secretory acini of the pancreas seem to lack a direct adrenergic supply. In the intrapancreatic ganglia, non-fluorescent nerve cells were reached by adrenergic terminals. No adrenergic nerve cells were detected in the pancreas of rats and cats. Small intensely fluorescent catecholamine-containing cells were observed in connexion with the intrapancreatic ganglia of rats.The research reported in this document has been sponsored by the Air Force Office of Scientific Research under grant AF EOAR 67-15 through the European Office of Aerospace Research (OAR), United States Air Force, by the United States Public Health Service (grant NB 06701-01) by the Swedish Medical Research Council (project B 67-12X-712-02A), and by the Faculty of Medicine, University of Lund, Sweden.     

Neuronal localization of dopamine and 5-Hydroxytryptamine in some mollusca

Summary The localization of biogenic monoamines in ganglionic tissues from Anodonta piscinalis, Helix pomatia, and Buccinum undatum has been studied by means of the histochemical fluorescence method of Falck and Hillarp.In cerebral, visceral, and pedal ganglia (besides nonfluorescent nerve cells) neurons emitting a green or yellow fluorescence were found. No other cell systems exhibiting a specific fluorescence were observed. An abundance of monoaminergic terminals were found in the central parts of these ganglia. Spectrophotofluorimetric determinations showed that there are large quantities of dopamine and 5-hydroxytryptamine in the tissues investigated. The amounts of dopamine and 5-hydroxytryptamine agree well with the distribution of green and yellow fluorescence, respectively, in the ganglia.There are many similarities between the vertebrate and the molluscan monoaminergic neurons. The morphology of the neurons is the same, the intraneuronal distribution of the monoamines is identical, depletion experiments with reserpine and denervation experiments give the same results, and the synaptic arrangement of monoaminergic fibres on non-adrenergic neurons has the same appearance. Apparently, however, dopamine and 5-hydroxytryptamine are the only monoamines acting as neuronal transmitters in the species investigated.The research reported in this document has been sponsored by the Air Force Office of Scientific Research under Grant AF EOAR 64-5 through the European Office of Aerospace Research (OAR), United States Air Force and by the Swedish Natural Science Research Council.     

An avoidance learning situation. A neural net model

A simple avoidance situation is considered in terms of a neural net learning model. Data for the control situation can be represented by an expression having three parameters which determine the initial and the steady state activities together with the transient aspects. The introduction of a learning parameter then allows one to calculate satisfactorily the results obtained in the experimental situation in which shock is applied. This research was supported in part by the United States Air Force through the Air Force Office of Scientific Research of the Air Research Development Command under Grant No. AF AFOSR 370-63 and in part by the United States Public Health Service Grant RCA GM K6 18,420.     

Body weight decreases in some proton exposed primates

ImmatureMacaca mulatta were exposed to varying doses of whole body irradiations utilizing 2 MeV X-rays; 55, 138 and 400 MeV protons; and 2.3 GeV protons. Over 200 primates remain in a life-long study of space type irradiation effects. Mean body weight decreases as a function of age, sex, dose and irradiation type have been found in the 55 MeV proton exposed group but not in the other groups. The cause of the decreased weights is unknown at iresent, as is the reason for the lack of this effect in the more penetrating irradiations.The animals involved in this study were maintained in accordance with theGuide for Laboratory Animal Facilities and Care as published by the National Academy of Sciences — National Research Council.The research reported in this paper was conducted by personnel of the Radiobiology Division, USAF School of Aerospace Medicine, Aerospace Medical Division, AFSC, United States Air Force, Brooks AFB, Texas. Further reproduction is authorized to satisfy the needs of the U.S. Government.     

Pigment migration and spectral sensitivity in the compound eye of moths

Summary The spectral sensitivity of dark adapted eyes of the moth Manduca sexta (Lepidoptera: Sphingidae) was measured between 350 and 650 nm by determining the relative number of photons necessary to elicit a retinal potential of 50 V. The spectral sensitivity was determined in eyes with the screening pigment: a) in the extreme distal position, b) in a proximal position, and c) with the pigment removed. Sensitivity maxima were found at about 350 to 370, 450 and 530 nm, irrespective of pigment position.Pigment movement is associated with a change in light attenuation of 2 to 3 log units at all wavelengths between 350 and 650 nm. Only small variations, about 0.6 log units, in screening effect were observed throughout the measured spectrum, and therefore the effect of pigment movement on spectral sensitivity is small.There is a slightly larger decline in sensitivity of eyes with the pigment removed compared to eyes with the pigment in the distal position at wavelengths above 530 nm. This result suggests that the distally located pigments have a slight screening effect.We are grateful to Dr. Bo Lindström for advice regarding the statistical treatment of the experimental data.This work was supported partly by the Swedish Medical Research Council, Stifteisen Gustaf och Tyra Svenssons Minne, Reservationsanslaget,and partly by the Air Force Office of Scientific Research through the European Office of Aerospace Research, OAR, United States Air Force under grant number EOOAR-68-0036.     

On visual adaptation: I. Photochemistry

Quantitative aspects of the photochemistry of visual adaptation are considered. A simplied model is given that fits data on changes of rhodopsin concentration during and following strong illumination. A variation on Wald’s compartment hypothesis is shown to fit the quasilinear dependence of log threshold upon pigment concentration. Finally, there is a brief review of pertinent data on cone pigments. This research was supported in part by the United States Air Force through the Air Force Office of Scientific Research of the Air Research Development Command under Contract No. AF(638)-414, and in part by the United States Public Health Service Training Grant 2G-833.