[ { "id": "authors:wf66q-pp560", "collection": "authors", "collection_id": "wf66q-pp560", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20191223-134154849", "type": "article", "title": "Quantifying olfactory perception: mapping olfactory perception space by using multidimensional scaling and self-organizing maps", "author": [ { "family_name": "Mamlouk", "given_name": "Amir Madany", "clpid": "Mamlouk-A-M" }, { "family_name": "Chee-Ruiter", "given_name": "Christine", "clpid": "Chee-Ruiter-C" }, { "family_name": "Hofmann", "given_name": "Ulrich G.", "clpid": "Hofmann-U-G" }, { "family_name": "Bower", "given_name": "James M.", "clpid": "Bower-J-M" } ], "abstract": "In this paper we describe an effort to project an olfactory perception database onto the nearest high dimensional Euclidean space using multidimensional scaling. This yields an independent Euclidean interpretation of odor perception, whether this space is metric or not. Self-organizing maps were then applied to produce two-dimensional maps of the Euclidean approximation of olfactory perception space. These maps provide new knowledge about complexity and potentially the functionality of the sense of smell from the point of view of human odor perception. This report is based on a recent thesis by Madany Mamlouk, Quantifying olfactory perception, at the University of L\u00fcbeck, Germany.", "doi": "10.1016/s0925-2312(02)00805-6", "issn": "0925-2312", "publisher": "Elsevier", "publication": "Neurocomputing", "publication_date": "2003-06", "volume": "52-54", "pages": "591-597" }, { "id": "authors:6xyge-nbj60", "collection": "authors", "collection_id": "6xyge-nbj60", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220223-918599000", "type": "article", "title": "The Influence of Somatosensory Cortex on Climbing Fiber Responses in the Lateral Hemispheres of the Rat Cerebellum after Peripheral Tactile Stimulation", "author": [ { "family_name": "Brown", "given_name": "Ian E.", "clpid": "Brown-Ian-E" }, { "family_name": "Bower", "given_name": "James M.", "clpid": "Bower-J-M" } ], "abstract": "This report describes the temporal relationship between the latency of responses to peripheral stimulation in primary somatosensory (SI) cerebral cortex and the timing of climbing fiber inputs to the lateral hemispheres of the rat cerebellum. Examined in the tactilely responsive regions of crus IIa in the rat, the results show that SI influences the timing of both evoked and spontaneous climbing fiber activity in these cerebellar regions without affecting the rate or probability of complex spike discharge. By reversibly blocking SI activity, we demonstrate that the absence of cortical input results in a lengthening of climbing fiber response latency to peripheral stimuli. Similarly, enhancing the cortical input by subthreshold electrical stimulation of SI results in a shortening of climbing fiber response latency. These results provide a new explanation for the tendency of the inferior olive to oscillate at 7\u201312 Hz and is consistent with the hypothesis that the inferior olive provides the cerebellum information about the timing of cortical computational cycles. Results are discussed in the context of previous and current hypotheses concerning the physiology and function of the inferior olive/climbing fiber system and are interpreted to provide additional evidence of a role for the cerebellum in the tactile somatosensory system.", "doi": "10.1523/jneurosci.22-15-06819.2002", "pmcid": "PMC6758178", "issn": "0270-6474", "publisher": "Society for Neuroscience", "publication": "Journal of Neuroscience", "publication_date": "2002-08-01", "series_number": "15", "volume": "22", "issue": "15", "pages": "6819-6829" }, { "id": "authors:wxgrw-yne72", "collection": "authors", "collection_id": "wxgrw-yne72", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20191112-103201813", "type": "article", "title": "Transient Versus Asymptotic Dynamics of CaM Kinase II: Possible Roles of Phosphatase", "author": [ { "family_name": "Kubota", "given_name": "Yoshihisa", "clpid": "Kubota-Yoshihisa" }, { "family_name": "Bower", "given_name": "James M.", "clpid": "Bower-J-M" } ], "abstract": "Calmodulin-dependent protein kinase II (CaMKII) is known to play a key role during induction of long-term potentiation (LTP). Given the dependence of LTP on the frequency of synaptic activation, several previous modeling efforts have proposed that biochemical properties of CaMKII itself might be in part responsible for this dependence. Recently, De Koninck and Schulman (1998) have provided direct experimental evidence that the enzyme itself is sensitive to the frequency of Ca\u00b2\u207a activation. Here we demonstrate the ability of a detailed biophysical model constructed solely on enzyme kinetics of purified proteins to generate the frequency sensitivity demonstrated by De Koninck and Schulman. Quantitative analysis of the model reveals that this frequency sensitivity is provided by a mechanism different from those previously postulated. This analysis leads to specific predictions concerning the effects of mutations on this process. We further employ the model to examine the asymptotic behavior of CaMKII-phosphatase system during longer simulated periods of stimulation. The analyses of the model suggest that the transient and asymptotic frequency sensitivity of this enzyme are dependent on different biochemical mechanisms. These results may be applicable to Ca\u00b2\u207a/calmodulin signaling pathways in general.", "doi": "10.1023/a:1013727331979", "issn": "0929-5313", "publisher": "Springer", "publication": "Journal of Computational Neuroscience", "publication_date": "2001-11", "series_number": "3", "volume": "11", "issue": "3", "pages": "263-279" }, { "id": "authors:n2y79-tg817", "collection": "authors", "collection_id": "n2y79-tg817", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20191009-081040948", "type": "article", "title": "Tactile Responses in the Granule Cell Layer of Cerebellar Folium Crus IIa of Freely Behaving Rats", "author": [ { "family_name": "Hartmann", "given_name": "Mitra J.", "clpid": "Hartmann-M-J" }, { "family_name": "Bower", "given_name": "James M.", "clpid": "Bower-J-M" } ], "abstract": "We recorded activity from the granule cell layer (GCL) of cerebellar folium Crus IIa as freely moving rats engaged in a variety of natural behaviors, including grooming, eating, and free tactile exploration. Multiunit responses in the 1000\u20134500 Hz range were found to be strongly correlated with tactile stimulation of lip and whisker (perioral) regions. These responses occurred regardless of whether the stimulus was externally or self-generated and during both active and passive touch. In contrast, perioral movements that did not tactually stimulate this region of the face (e.g., chewing) produced no detectable increases in GCL activity. In addition, GCL responses were not correlated with movement extremes. When rats used their lips actively for palpation and exploration, the tactile responses in the GCL were not detectably modulated by ongoing jaw movements. However, active palpation and exploratory behaviors did result in the largest and most continuous bursts of GCL activity: responses were on average 10% larger and 50% longer during palpation and exploration than during grooming or passive stimulation. Although activity levels differed between behaviors, the position and spatial extent of the peripheral receptive field was similar over all behaviors that resulted in tactile input. Overall, our data suggest that the 1000\u20134500 Hz multiunit responses in the Crus IIa GCL of awake rats are correlated with tactile input rather than with movement or any movement parameter and that these responses are likely to be of particular importance during the acquisition of sensory information by perioral structures.", "doi": "10.1523/jneurosci.21-10-03549.2001", "pmcid": "PMC6762470", "issn": "0270-6474", "publisher": "Society for Neuroscience", "publication": "Journal of Neuroscience", "publication_date": "2001-05-15", "series_number": "10", "volume": "21", "issue": "10", "pages": "3549-3563" }, { "id": "authors:2g2pn-8z781", "collection": "authors", "collection_id": "2g2pn-8z781", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141124-133435273", "type": "article", "title": "An impairment in sniffing contributes to the olfactory impairment in Parkinson's disease", "author": [ { "family_name": "Sobel", "given_name": "Noam", "clpid": "Sobel-N" }, { "family_name": "Thomason", "given_name": "Moriah E.", "clpid": "Thomason-M-E" }, { "family_name": "Tanner", "given_name": "Caroline M.", "clpid": "Tanner-C-M" }, { "family_name": "Tetrud", "given_name": "James W.", "clpid": "Tetrud-J-W" }, { "family_name": "Bower", "given_name": "James M.", "clpid": "Bower-J-M" }, { "family_name": "Sullivan", "given_name": "Edith V.", "clpid": "Sullivan-E-V" }, { "family_name": "Gabrieli", "given_name": "John D. E.", "clpid": "Gabrieli-J-D-E" } ], "abstract": "Although the presence of an olfactory impairment in Parkinson's disease (PD) has been recognized for 25 years, its cause remains unclear. Here we suggest a contributing factor to this impairment, namely, that PD impairs active sniffing of odorants. We tested 10 men and 10 women with clinically typical PD, and 20 age- and gender-matched healthy controls, in four olfactory tasks: (i) the University of Pennsylvania smell identification test; (ii and iii) detection threshold tests for the odorants vanillin and propionic acid; and (iv) a two-alternative forced-choice detection paradigm during which sniff parameters (airflow peak rate, mean rate, volume, and duration) were recorded with a pneomatotachograph-coupled spirometer. An additional experiment tested the effect of intentionally increasing sniff vigor on olfactory performance in 20 additional patients. PD patients were significantly impaired in olfactory identification (P < 0.0001) and detection (P < 0.007). As predicted, PD patients were also significantly impaired at sniffing, demonstrating significantly reduced sniff airflow rate (P < 0.01) and volume (P < 0.002). Furthermore, a patient's ability to sniff predicted his or her performance on olfactory tasks, i.e., the more poorly patients sniffed, the worse their performance on olfaction tests (P < 0.009). Finally, increasing sniff vigor improved olfactory performance in those patients whose baseline performance had been poorest (P < 0.05). These findings implicate a sniffing impairment as a component of the olfactory impairment in PD and further depict sniffing as an important component of human olfaction.", "doi": "10.1073/pnas.071061598", "pmcid": "PMC31195", "issn": "0027-8424", "publisher": "National Academy of Sciences", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "publication_date": "2001-03-27", "series_number": "7", "volume": "98", "issue": "7", "pages": "4154-4159" }, { "id": "authors:gvvxf-0kz75", "collection": "authors", "collection_id": "gvvxf-0kz75", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200615-085157732", "type": "article", "title": "The human red nucleus and lateral cerebellum in supporting roles for sensory information processing", "author": [ { "family_name": "Liu", "given_name": "Yijun", "clpid": "Liu-Yijun" }, { "family_name": "Pu", "given_name": "Yonglin", "clpid": "Pu-Yonglin" }, { "family_name": "Gao", "given_name": "Jia-Hong", "clpid": "Gao-Jia-Hong" }, { "family_name": "Parsons", "given_name": "Lawrence M.", "clpid": "Parsons-L-M" }, { "family_name": "Xiong", "given_name": "Jinhu", "clpid": "Xiong-Jinhu" }, { "family_name": "Liotti", "given_name": "Mario", "clpid": "Liotti-M" }, { "family_name": "Bower", "given_name": "James M.", "clpid": "Bower-J-M" }, { "family_name": "Fox", "given_name": "Peter T.", "clpid": "Fox-P-T" } ], "abstract": "A functional MRI study compared activation in the red nucleus to that in the lateral cerebellar dentate nucleus during passive and active tactile discrimination tasks. The study pursued recent neuroimaging results suggesting that the cerebellum may be more associated with sensory processing than with the control of movement for its own sake. Because the red nucleus interacts closely with the cerebellum, the possibility was examined that activity in red nucleus might also be driven by the requirement for tactile sensory processing with the fingers rather than by finger movement alone. The red and dentate nuclei were about 300% more active (a combination of activation areas and intensities) during passive (non\u2010motor) tactile stimulation when discrimination was required than when it was not. Thus, the red nucleus was activated by purely sensory stimuli even in the absence of the opportunity to coordinate finger movements or to use the sensory cues to guide movement. The red and dentate nuclei were about 70% more active during active tactile tasks when discrimination was required than when it was not (i.e., for simple finger movements alone). Thus, the red nucleus was most active when the fingers were being used for tactile sensory discrimination. In both the passive and active tactile tasks, the observed activation had a contralateralized pattern, with stronger activation in the left red nucleus and right dentate nucleus. Significant covariation was observed between activity in the red nucleus and the contralateral dentate during the discrimination tasks and no significant correlation between the red nucleus and the contralateral dentate activity was detected during the two non\u2010discrimination tasks. The observed interregional covariance and contralateralized activation patterns suggest strong functional connectivity during tactile discrimination tasks. Overall, the pattern of findings suggests that the activity in the red nucleus, as in the lateral cerebellum, is more driven by the requirements for sensory processing than by motor coordination per se.", "doi": "10.1002/1097-0193(200008)10:4<147::aid-hbm10>3.0.co;2-u", "pmcid": "PMC6872052", "issn": "1065-9471", "publisher": "Wiley", "publication": "Human Brain Mapping", "publication_date": "2000-08", "series_number": "4", "volume": "10", "issue": "4", "pages": "147-159" }, { "id": "authors:bs554-81h94", "collection": "authors", "collection_id": "bs554-81h94", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20191028-114852403", "type": "article", "title": "Synaptic Control of Spiking in Cerebellar Purkinje Cells: Dynamic Current Clamp Based on Model Conductances", "author": [ { "family_name": "Jaeger", "given_name": "Dieter", "clpid": "Jaeger-D" }, { "family_name": "Bower", "given_name": "James M.", "clpid": "Bower-J-M" } ], "abstract": "Previous simulations using a realistic model of a cerebellar Purkinje cell suggested that synaptic control of somatic spiking in this cell type is mediated by voltage-gated intrinsic conductances and that inhibitory rather than excitatory synaptic inputs are more influential in controlling spike timing. In this paper, we have tested these predictions physiologically using dynamic current clamping to apply model-derived synaptic conductances to Purkinje cells in vitro. As predicted by the model, this input transformed thein vitro pattern of spiking into a different spike pattern typically observed in vivo. A net inhibitory synaptic current was required to achieve such spiking, indicating the presence of strong intrinsic depolarizing currents. Spike-triggered averaging confirmed that the length of individual intervals between spikes was correlated to the amplitude of the inhibitory conductance but was not influenced by excitatory inputs. Through repeated presentation of identical stimuli, we determined that the output spike rate was very sensitive to the relative balance of excitation and inhibition in the input conductances. In contrast, the accuracy of spike timing was dependent on input amplitude and was independent of spike rate. Thus, information could be encoded in Purkinje cell spiking in a precise spike time code and a rate code at the same time. We conclude that Purkinje cell responses to synaptic input are strongly dependent on active somatic and dendritic properties and that theories of cerebellar function likely need to incorporate single-cell dynamics to a greater degree than is customary.", "doi": "10.1523/jneurosci.19-14-06090.1999", "pmcid": "PMC6783079", "issn": "0270-6474", "publisher": "Society for Neuroscience", "publication": "Journal of Neuroscience", "publication_date": "1999-07-15", "series_number": "14", "volume": "19", "issue": "14", "pages": "6090-6101" }, { "id": "authors:74jny-2k396", "collection": "authors", "collection_id": "74jny-2k396", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:CROnc98", "type": "article", "title": "Spike frequency adaptation affects the synchronization properties of networks of cortical oscillators", "author": [ { "family_name": "Crook", "given_name": "Sharon M.", "clpid": "Crook-S-M" }, { "family_name": "Ermentrout", "given_name": "G. Bard", "clpid": "Ermentrout-G-B" }, { "family_name": "Bower", "given_name": "James M.", "clpid": "Bower-J-M" } ], "abstract": "Oscillations in many regions of the cortex have common temporal characteristics with dominant frequencies centered around the 40 Hz (gamma) frequency range and the 5\u201310 Hz (theta) frequency range. Experimental results also reveal spatially synchronous oscillations, which are stimulus dependent (Gray&Singer, 1987;Gray, K\u00f6nig, Engel, & Singer, 1989; Engel, K\u00f6nig, Kreiter, Schillen, & Singer, 1992). This rhythmic activity suggests that the coherence of neural populations is a crucial feature of cortical dynamics (Gray, 1994). Using both simulations and a theoretical coupled oscillator approach, we demonstrate that the spike frequency adaptation seen in many pyramidal cells plays a subtle but important role in the dynamics of cortical networks. Without adaptation, excitatory connections among model pyramidal cells are desynchronizing. However, the slow processes associated with adaptation encourage stable synchronous behavior.", "doi": "10.1162/089976698300017511", "issn": "0899-7667", "publisher": "MIT Press", "publication": "Neural Computation", "publication_date": "1998-05-15", "series_number": "4", "volume": "10", "issue": "4", "pages": "837-854" }, { "id": "authors:vffv9-raf36", "collection": "authors", "collection_id": "vffv9-raf36", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20191030-150138163", "type": "article", "title": "The Role of Synaptic and Voltage-Gated Currents in the Control of Purkinje Cell Spiking: A Modeling Study", "author": [ { "family_name": "Jaeger", "given_name": "Dieter", "clpid": "Jaeger-Dieter" }, { "family_name": "De Schutter", "given_name": "Erik", "clpid": "De-Schutter-Erik" }, { "family_name": "Bower", "given_name": "James M.", "clpid": "Bower-J-M" } ], "abstract": "We have used a realistic computer model to examine interactions between synaptic and intrinsic voltage-gated currents during somatic spiking in cerebellar Purkinje cells. We have shown previously that this model generates realistic in vivo patterns of somatic spiking in the presence of continuous background excitatory and inhibitory input (De Schutter and Bower, 1994b). In the present study, we analyzed the flow of synaptic and intrinsic currents across the dendritic membrane and the interaction between the soma and dendrite underlying this spiking behavior. This analysis revealed that: (1) dendritic inward current flow was dominated by a noninactivating P-type calcium current, resulting in a continuous level of depolarization; (2) the mean level of this depolarization was controlled by the mean rate of excitatory and inhibitory synaptic input; (3) the synaptic control involved a voltage-clamping mechanism exerted by changes of synaptic driving force at different membrane potentials; (4) the resulting total current through excitatory and inhibitory synapses was near-zero, with a small outward bias opposing the P-type calcium current; (5) overall, the dendrite acted as a variable current sink with respect to the soma, slowing down intrinsic inward currents in the soma; (6) the somato-dendritic current showed important phasic changes during each spike cycle; and (7) the precise timing of somatic spikes was the result of complex interactions between somatic and dendritic currents that did not directly reflect the timing of synaptic input. These modeling results suggest that Purkinje cells act quite differently from simple summation devices, as has been assumed previously in most models of cerebellar function. Specific physiologically testable predictions are discussed.", "doi": "10.1523/jneurosci.17-01-00091.1997", "pmcid": "PMC6793698", "issn": "0270-6474", "publisher": "Society for Neuroscience", "publication": "Journal of Neuroscience", "publication_date": "1997-01-01", "series_number": "1", "volume": "17", "issue": "1", "pages": "91-106" }, { "id": "authors:vs1rr-8m339", "collection": "authors", "collection_id": "vs1rr-8m339", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141208-105813783", "type": "article", "title": "Cerebellum implicated in sensory acquisition and discrimination rather than motor control", "author": [ { "family_name": "Gao", "given_name": "Jia-Hong", "clpid": "Gao-J-H" }, { "family_name": "Parsons", "given_name": "Lawrence M.", "clpid": "Parsons-L-M" }, { "family_name": "Bower", "given_name": "James M.", "clpid": "Bower-J-M" }, { "family_name": "Xiong", "given_name": "Jinhu", "clpid": "Xiong-J" }, { "family_name": "Li", "given_name": "Jinqi", "clpid": "Li-J" }, { "family_name": "Fox", "given_name": "Peter T.", "clpid": "Fox-P-T" } ], "abstract": "Recent evidence that the cerebellum is involved in perception and cognition challenges the prevailing view that its primary function is fine motor control. A new alternative hypothesis is that the lateral cerebellum is not activated by the control of movement per se, but is strongly engaged during the acquisition and discrimination of sensory information. Magnetic resonance imaging of the lateral cerebellar output (dentate) nucleus during passive and active sensory tasks confirmed this hypothesis. These findings suggest that the lateral cerebellum may be active during motor, perceptual, and cognitive performances specifically because of the requirement to process sensory data.", "doi": "10.1126/science.272.5261.545", "issn": "0036-8075", "publisher": "American Association for the Advancement of Science", "publication": "Science", "publication_date": "1996-04-26", "series_number": "5261", "volume": "272", "issue": "5261", "pages": "545-547" }, { "id": "authors:4ptpg-wq371", "collection": "authors", "collection_id": "4ptpg-wq371", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141208-105205093", "type": "article", "title": "Simulated responses of cerebellar Purkinje cells are independent of the dendritic location of granule cell synaptic inputs", "author": [ { "family_name": "De Schutter", "given_name": "Erik", "clpid": "De-Schutter-E" }, { "family_name": "Bower", "given_name": "James M.", "clpid": "Bower-J-M" } ], "abstract": "Cerebellar Purkinje cell responses to granule cell synaptic inputs were examined with a computer model including active dendritic conductances. Dendritic P-type Ca^2+ channels amplified postsynaptic responses when the model was firing at a physiological rate. Small synchronous excitatory inputs applied distally on the large dendritic tree resulted in somatic responses of similar size to those generated by more proximal inputs. In contrast, in a passive model the somatic postsynaptic potentials to distal inputs were 76% smaller. The model predicts that the somatic firing response of Purkinje cells is relatively insensitive to the exact dendritic location of synaptic inputs. We describe a mechanism of Ca^2+-mediated synaptic amplification, based on the subspiking threshold recruitment of P-type Ca^2+ channels in the dendritic branches surrounding the input site.", "doi": "10.1073/pnas.91.11.4736", "pmcid": "PMC43863", "issn": "0027-8424", "publisher": "National Academy of Sciences", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "publication_date": "1994-05-24", "series_number": "11", "volume": "91", "issue": "11", "pages": "4736-4740" }, { "id": "authors:0t3st-7tw20", "collection": "authors", "collection_id": "0t3st-7tw20", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:SCHUnc93", "type": "article", "title": "Sensitivity of synaptic plasticity to the Ca^(2+) permeability\n of NMDA channels : a model of long-term potentiation\n in hippocampal neurons", "author": [ { "family_name": "De Schutter", "given_name": "Erik", "clpid": "De-Schutter-E" }, { "family_name": "Bower", "given_name": "James M.", "clpid": "Bower-J-M" } ], "abstract": "We have examined a model by Holmes and Levy (1990) of the induction of associative long-term potentiation (LTP) by a rise in the free Ca^(2+) concentration ([Ca^(2+)]) after synaptic activation of dendritic spines. The previously reported amplification of the change in [Ca^(2+)] caused by coactivation of several synapses was found to be quite sensitive to changes in the permeability of the N-methyl-D-aspartate (NMDA) receptor channels to Ca^(2+). Varying this parameter indicated that maximum amplification is obtained at values that are close to Ca^(2+) permeabilities reported in the literature. However, amplification failed if permeability is reduced by more than 50%. We also found that the maximum free [Ca^(2+)] reached in an individual spine during synaptic coactivation of several spines depended on the location of that spine on the dendritic tree. Distal spines attained a higher [Ca^(2+)] than proximal ones, with differences of up to 80%. The implications of this result for the uniformity of induction of associative LTP in spines in different regions of the dendrite are discussed.", "doi": "10.1162/neco.1993.5.5.681", "issn": "0899-7667", "publisher": "MIT Press", "publication": "Neural Computation", "publication_date": "1993-09", "series_number": "5", "volume": "5", "issue": "5", "pages": "681-694" }, { "id": "authors:7xcvr-fjf54", "collection": "authors", "collection_id": "7xcvr-fjf54", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130816-103134921", "type": "article", "title": "Experimentalists and modelers: can we all just get along?", "author": [ { "family_name": "Bower", "given_name": "James M.", "clpid": "Bower-J-M" }, { "family_name": "Koch", "given_name": "Christof", "orcid": "0000-0001-6482-8067", "clpid": "Koch-C" } ], "abstract": "How can the interaction between theoretical neuro-scientists and their experimental counterparts be improved? This article discusses a number of suggestions relating to the presentation of data in experimental studies. In particular, published data should account for the diversity of response properties encountered, rather than concentrating on the 'representative' response, as well as emphasizing the stochastic nature of neurons by routinely including raw, unprocessed data from individual trials, which show the degree of variability prior to averaging.", "doi": "10.1016/0166-2236(92)90010-6", "issn": "0166-2236", "publisher": "Elsevier", "publication": "Trends in Neurosciences", "publication_date": "1992", "series_number": "11", "volume": "15", "issue": "11", "pages": "458-61" }, { "id": "authors:ne177-wv489", "collection": "authors", "collection_id": "ne177-wv489", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:WILnc91", "type": "article", "title": "A computer simulation of oscillatory behavior in primary visual cortex", "author": [ { "family_name": "Wilson", "given_name": "Matthew A.", "clpid": "Wilson-M-A" }, { "family_name": "Bower", "given_name": "James M.", "clpid": "Bower-J-M" } ], "abstract": "Periodic variations in correlated cellular activity have been observed in many regions of the cerebral cortex. The recent discovery of stimulus-dependent, spatially-coherent oscillations in primary visual cortex of the cat has led to suggestions of neural information encoding schemes based on phase and/or frequency variation. To explore the mechanisms underlying this behavior and their possible functional consequences, we have developed a realistic neural model, based on structural features of visual cortex, which replicates observed oscillatory phenomena. In the model, this oscillatory behavior emerges directly from the structure of the cortical network and the properties of its intrinsic neurons; however, phase coherence is shown to be an average phenomenon seen only when measurements are made over multiple trials. Because average coherence does not ensure synchrony of firing over the course of single stimuli, oscillatory phase may not be a robust strategy for directly encoding stimulus-specific information. Instead, the phase and frequency of cortical oscillations may reflect the coordination of general computational processes within and between cortical areas. Under this interpretation, coherence emerges as a result of horizontal interactions that could be involved in the formation of receptive field properties.", "doi": "10.1162/neco.1991.3.4.498", "issn": "0899-7667", "publisher": "MIT Press", "publication": "Neural Computation", "publication_date": "1991-12", "series_number": "4", "volume": "3", "issue": "4", "pages": "498-509" }, { "id": "authors:y9c3y-brk20", "collection": "authors", "collection_id": "y9c3y-brk20", "cite_using_url": "https://resolver.caltech.edu/CaltechAUTHORS:BOWpnas86", "type": "article", "title": "Facilitating and nonfacilitating synapses on pyramidal cells: a correlation between physiology and morphology", "author": [ { "family_name": "Bower", "given_name": "James M.", "clpid": "Bower-J-M" }, { "family_name": "Haberly", "given_name": "Lewis B.", "clpid": "Haberly-L-B" } ], "abstract": "Pyramidal cells in piriform cortex receive excitatory inputs from two different sources that are segregated onto adjacent segments of their apical dendrites. The present studies show that excitatory postsynaptic potentials (EPSPs) evoked by primary olfactory tract afferents that terminate on distal apical segments display paired shock facilitation whereas ESPSs evoked by intrinsic association fibers that terminate on proximal apical segments do not. An ultrastructural comparison of the presynaptic elements of these two fiber systems has revealed that the facilitating olfactory tract afferent synapses have a much lower packing density of synaptic vesicles than do the nonfacilitating association fiber synapses. Further, a search of the literature has revealed that where both morphological and physiological data are available for the same synapses, this same correlation appears to apply. We propose a hypothesis to account for this correlation based on synaptic vesicles to buffer internal calcium and the biochemical characteristics of preterminal calcium-dependent mechanisms affecting the number of vesicles available for release.", "doi": "10.1073/pnas.83.4.1115", "pmcid": "PMC323022", "issn": "0027-8424", "publisher": "National Academy of Sciences", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "publication_date": "1986-02-01", "series_number": "4", "volume": "83", "issue": "4", "pages": "1115-1119" } ]