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Presents an obituary for Karl H. Pribram, who died on January 19, 2015. Karl had a very successful and extensive 70-year career in neuroscience research. He was a prolific researcher and writer, publishing approximately 150 data papers, almost 300 theoretical papers, and 19 books. His work is recognized through many awards and titles, including a Doctorate in Psychology from the University of Montreal in 1992, a Doctorate in Philosophy from the University of Bremen (1996), and a lifetime achievement award from the International Neural Network Society. His professional interactions extended beyond the traditional boundaries of science into the arts and humanities. His work in these integrative areas resulted in his becoming the first recipient of the Baclav Havel Prize for integrating science with the humanities and arts.

A regression-based meta-analysis examined the degree to which the effects of a family history of hypertension on cardiovascular reactivity are moderated by the magnitude of cardiovascular responses elicited in challenge/task conditions. Mean change scores for negative family history groups were regressed on mean change scores for positive family history groups. The slopes of separate regression lines obtained for systolic and diastolic blood pressure and heart rate were significantly less than 1.0 and the y-intercepts for these regression lines were significantly greater than zero. This pattern indicates that family history differences in cardiovascular reactivity to stress are greatest in situations that elicit the smallest baseline-stressor change scores in non-family-history groups.

This study examined age differences in the factor structure of EEG using a 128-electrode system. Running EEG records were obtained from healthy younger and healthy older adults before, during, and after they performed a 13-minute Continuous Performance Task. Factor analyses were conducted on each five-second segment of EEG data by treating the voltages obtained at each electrode site as variables and each measurement epoch as a case. Results showed that the EEG records of older adults yielded significantly more factors than those of younger adults in every task condition. In addition, eigenvalues for the first common factor derived from EEG data sets were significantly larger in the EEG recordings of younger adults than older adults. The results are interpreted to indicate a greater degree of complexity in the spatial distribution of EEG activity in older adults, possibly reflecting an age-related decrease in the degree of coordination among cortical areas.

This study describes the results of experiments motivated by an attempt to understand spectral processing in the cerebral cortex (DeValois and DeValois, 1988; Pribram, 1971, 1991). This level of inquiry concerns processing within a restricted cortical area rather than that by which spatially separate circuits become synchronized during certain behavioral and experiential processes. We recorded neural responses for 55 locations in the somatosensory (barrel) cortex of the rat to various combinations of spatial frequency (texture) and temporal frequency stimulation of their vibrissae. The recordings obtained from single and multi-unit bursts of spikes were mapped as surface distributions of local dendritic potentials. The distributions showed a variety of patterns that are asymmetric with respect to the spatial and temporal parameters of stimulation, and were, therefore, not simply reflecting whisker flick rate. Next, a simulation of our results showed that these surface distributions of local dendritic potentials can be described by Gabor-like functions much as in the visual system. The results provide support for a model of distributed cortical processing that imposes a physiologically derived frame (the limited extent of a dendritic patch) and an anatomically derived (axonal) sampling of the distributed process. This combination provides a complex Gabor wavelet that encodes phase, which is necessary to processing such details as edges and texture in a scene. The synchronization across cortical areas that make the Gabor wavelet processes within restricted cortical areas available to one another (the binding problem) proceed at a ''higher order'' level of integration. Both levels of distributed processing accomplish computation in the conjoint spacetime and spectral domain.

Eighteen older adults and 18 younger adults were compared on two quantitative measures describing changes over time in the spatial distribution of running EEG. EEG was collected from 128 electrodes under resting eyes-open and eyes-closed conditions and during performance of a 13 minute sustained attention task. One EEG measure, the recrudescence rate, represented the number of changes in the location of the highest squared voltage per second. A second EEG measure consisted of the algorithmic complexity of changes in the location of the highest squared voltage over time. Regardless of the task condition, older adults had significantly higher scores than younger adults on both the recrudescence rate and the measure of algorithmic complexity. The implications of the results for neurologically-based theories of performance declines in older adults are discussed.

Contents: K.H. Pribram, Foreword. K. Lorenz, Keynote: Innate Bases of Learning. Part I:The Behavioral Level: Learning. D.M. Rumbaugh, Respondents, Operants, and Emergents. W.J. McIlvane, Analysis of Behavioral Selection by Consequences and Its Potential: Contributions to Understanding Brain-Behavior Relations. P.R. Killeen, Mechanics of the Animate. P.R. Killeen, L.A. Bizo, The Response Dimension. M. Stadler, Nonlinear Phenomena in Learning Processes. L. Greeley, The Attractor of the Intentional Learning System. Part II:The Network Level: Self-Organization. S.C. Kak, The Three Languages of the Brain: Quantum, Reorganizational, and Associative. T. Kohonen, Automatic Formation of Wavelet- and Gabor-Type Filters in an Adaptive-Subspace SOM. D. Stassinopoulos, P. Bak, Democratic Reinforcement: Learning via Self-Organization. D.L. Alkon, K.T. Blackwell, G.S. Barbour, S.A. Werness, T.P. Vogl, Biological Plausibility of Synaptic Associative Memory Models. P.J. Werbos, Learning in the Brain: An Engineering Interpretation. Part III:The Neural Systems Level: Process. J.W. Brown, Morphogenesis and Mental Process. H.W. Hanlon, Topographically Different Regional Networks Impose Structural Limitations on Both Sexes in Early Postnatal Development. D.L. Schacter, E. Reiman, A. Uecker, M.R. Polster, L.S. Yun, L.A. Cooper, Brain Regions Associated With Retrieval of Structurally Coherent Visual Information. D.L. Schacter, N.M. Alpert, C.R. Savage, S.L. Rauch, M.S. Albert, Conscious Recollection and the Human Hippocampal Formation: Evidence from Positron Emmission Tomography. R.P. Kesner, An Exploration of the Neural Bases of Memory Representations of Reward and Context. D.D. de Grandpre, D.M. Tucker, Emotion and the Self-Organization of Semantic Memory. Part IV:The Social Level: The Organization of Self in Society. W.J. Freeman, Learning and Unlearning in the Formation of Social Bonds. A. Gregory, Language as an Instrument for Self Reorganization. R.T. Bradley, K.H. Pribram, Self-Organization and the Social Collective. Part V:The Transcendental Level: Self-Organization on a Grand Scale. S.C. Kak, Reflections in Clouded Mirrors: Selfhood in Animals and Machines. H.P. Stapp, Chance, Choice, and Consciousness: A Causal Quantum Theory of the Mind/Brain. B.J. Hiley, Mind and Matter: Aspects of the Implicate Order Described Through Algebra. J.S. King, K.H. Pribram, Afterword.

Contents: J. King, Foreword. Part I:The Macrolevel: Issues. J.R. Searle, The Problem of Consciousness. B.J. MacLennan, The Investigation of Consciousness Through Phenomenology and Neuroscience. Part II:The Mesolevel: Neural Systems and Consciousness. L. Weiskrantz, Blindsight: Conscious vs. Unconscious Aspects. C.L. Colby, J.-R. Duhamel, Heterogeneity of Extrastriate Visual Areas and Multiple Parietal Areas in the Macaque Monkey. M. Mishkin, Cerebral Memory Circuits. E.K. Miller, Neocortical Mechanisms for Visual Memory. M.S.A. Graziano, C.G. Gross, From Eye to Hand. Part III:Microprocessing and the Nanolevel in the Neurodynamics of Consciousness. J.K. Chapin, M.A.L. Nicolelis, Beyond Single Unit Recording: Characterizing Neural Information in Networks of Simultaneously Recorded Neurons. M. SantaMaria, J. King, M. Xie, B. Zheng, K. Pribram, D. Doherty, Responses of Somatosensory Cortical Neurons to Spatial Frequency and Orientation: A Progress Report. J. Sutherland, Application Toolset for Holographic Neural Technology: An Overview. H.H. Szu, Attempts to Unify Chaos, Fuzzy Logic and Neural Networks. S. Hameroff, R. Penrose, Orchestrated Reduction of Quantum Coherence in Brain Microtubules: A Model for Consciousness. Part IV:Quantum Physics, Quantum Neurodynamics and Consciousness. H.P. Stapp, Why Classical Mechanics Cannot Naturally Accommodate Consciousness But Quantum Mechanics Can. B.J. Hiley, Nonlocality in Microsystems. L.I. Gould, Quantum Dynamics and Neural Dynamics: Analogies Between the Formalisms of Bohm and Pribram. R.L. Amoroso, B.E. Martin, Modeling the Heisenberg Matrix: Quantum Coherence and Thought at the Holoscape Manifold and Deeper Complementarity. G. Vitiello, Dissipation and Brain. F. Frohlich, G.J. Hyland, Frohlich Coherence at the Mind-Brain Interface. K.H. Pribram, Afterword.

This paper describes methods for quantifying the spatiotemporal dynamics of EEG. Development of these methods was motivated by watching computer-generated animations of EEG voltage records. These animations contain a wealth of information about the pattern of change across time in the voltages observed across the surface of the scalp. In an effort to quantify this pattern of changing voltages, we elected to extract a single quantifiable feature from each measurement epoch, the highest squared voltage among the various electrode sites. Nineteen channels of EEG were collected from subjects using an electrode cap with standard 10-20 system placements. Two minute records were obtained. Each record was sampled at a rate of 200 per second. Thirty seconds of artifact-free data were extracted from each 2 minute record. An algorithm then determined the location of the channel with the greatest amplitude for each 5 msec sampling epoch. We quantified these spatio-temporal dynamics as scalars, vectors and cluster analytic plots of EEG activity for finger tapping, cognitive effort (counting backwards) and relaxation to illustrate the utility of the techniques.

This study examined age differences in the factor structure of EEG using a 128-electrode system. Running EEG records were obtained from healthy younger and healthy older adults before, during, and after they performed a 13-minute Continuous Performance Task. Factor analyses were conducted on each five-second segment of EEG data by treating the voltages obtained at each electrode site as variables and each measurement epoch as a case. Results showed that the EEG records of older adults yielded significantly more factors than those of younger adults in every task condition. In addition, eigenvalues for the first common factor derived from EEG data sets were significantly larger in the EEG recordings of younger adults than older adults. The results are interpreted to indicate a greater degree of complexity in the spatial distribution of EEG activity in older adults, possibly reflecting an age-related decrease in the degree of coordination among cortical areas.

SummaryOf the various factors influencing the volume transferred by the loop in the automated plate loop technique for enumerating bacteria in milk, the speed of the loop as it emerged from the milk sample was the most important. Increasing this speed from 3 to 6 cm/s resulted in a 23% increase in volume transferred by a standard loop of internal diam. 1·45 mm. The depth of dip was also important, but changes in temperature of the sample from 5 to 20 °C caused no significant change in volume transferred. The results indicate that if the transfer of 1 µl milk is required at speeds commonly used in the automated plate loop technique, the internal diam. of the loop should be reduced from the present standard 1·45 to 1·3 mm.

SUMMARYThe effects of concentrations of 10–30 mM/1 of CO2on the growth of psychrotrophic milk spoilage organisms were examined, both in untreated whole milk and in pure cultures ofPseudomonas fluorescensgrowing in skim-milk and broth. Spoilage of refrigerated untreated whole milk was found to be inhibited by the addition of CO2and the effect was enhanced with increasing concentrations of CO2and decreasing storage temperature. Experiments with pure cultures ofPs. fluorescensshowed that the inhibitory effects of CO2were not due to increased acidity or to displacement of dissolved O2, but to the presence of CO2per sewhich induced an increase in the duration of the lag phase of growth and had only a small effect on the logarithmic phase.

SUMMARYA commercial neutral proteinase was encapsulated in liposomes (multilamellar) and incorporated into cheese curd via the cheese milk. The milk proteins were protected from proteinase attack during curd manufacture. A significant proportion of the liposome-entrapped enzyme was retained in the curd and its subsequent release into the cheese matrix was inferred from an increased rate of β-casein breakdown.