self-organising map
... •Only the winning neuron and neurons inside its neighbourhood have their weights adapted. All the other neurons have no change in their weights. •A method for deriving the weight update equations for the SOM model is based on a modified form of Hebbian learning. There is a forgetting term in the sta ...
... •Only the winning neuron and neurons inside its neighbourhood have their weights adapted. All the other neurons have no change in their weights. •A method for deriving the weight update equations for the SOM model is based on a modified form of Hebbian learning. There is a forgetting term in the sta ...
Mirror neurons responding to the observation of ingestive and
... a three-dimensional (3-D) system. This system is constituted of two video-cameras (xc-999p, SONY), a 3-D to 2-D switching box (vrmux2p, VREX), a card and a 3-D projector (VR2100, VREX). Several different hand and mouth actions performed by the experimenter or by the monkey were recorded. Most of the ...
... a three-dimensional (3-D) system. This system is constituted of two video-cameras (xc-999p, SONY), a 3-D to 2-D switching box (vrmux2p, VREX), a card and a 3-D projector (VR2100, VREX). Several different hand and mouth actions performed by the experimenter or by the monkey were recorded. Most of the ...
Neural Encoding I: Firing Rates and Spike Statistics
... synaptic connections with other neurons per mm of length while the dendritic tree receives, on average, 2 synaptic inputs per µm. The cell body or soma of a typical cortical neurons ranges in diameter from about 10 to 50 µm. Along with these morphological features, neurons have physiological special ...
... synaptic connections with other neurons per mm of length while the dendritic tree receives, on average, 2 synaptic inputs per µm. The cell body or soma of a typical cortical neurons ranges in diameter from about 10 to 50 µm. Along with these morphological features, neurons have physiological special ...
Basal Forebrain Cholinergic System Is Involved in Rapid Nerve
... icits in both area and projection density of BF cells to the cortex. It is clear that NGF plays a role in maintaining the BF cholinergic projections to the cortex. Two key findings have also suggested the possibility that NGF can also induce immediate release of ACh. Knipper and collaborators obtain ...
... icits in both area and projection density of BF cells to the cortex. It is clear that NGF plays a role in maintaining the BF cholinergic projections to the cortex. Two key findings have also suggested the possibility that NGF can also induce immediate release of ACh. Knipper and collaborators obtain ...
Contribution of Pedunculopontine Tegmental Nucleus Neurons to
... only for the tests pertaining to reward responses. To evaluate the relationship between neuronal discharge and specific events, we produced rasters and continuously varying spike density functions (Richmond et al. 1987) aligned on the events. To generate the spike density function, a Gaussian pulse ...
... only for the tests pertaining to reward responses. To evaluate the relationship between neuronal discharge and specific events, we produced rasters and continuously varying spike density functions (Richmond et al. 1987) aligned on the events. To generate the spike density function, a Gaussian pulse ...
elaboration, remodeling and spatial organization of
... distribution patterns was performed in the MBs where clones of mCD8-GFP-postive dendrites happened to alternate with clones of rCD2-labeled dendrites (e.g. Fig. 2C). When the MBs were photo-sectioned from the cell body region to the lobes (Fig. 2B), we noticed that two front clones (AM and AL) flank ...
... distribution patterns was performed in the MBs where clones of mCD8-GFP-postive dendrites happened to alternate with clones of rCD2-labeled dendrites (e.g. Fig. 2C). When the MBs were photo-sectioned from the cell body region to the lobes (Fig. 2B), we noticed that two front clones (AM and AL) flank ...
Chemosensory pathways in the brainstem controlling
... spinal motor neurons controlling respiratory muscles. Cardiovascular sympathetic and vagal activities have characteristic discharges that are patterned by respiratory activity. This patterning ensures ventilation– perfusion matching for optimal respiratory gas exchange within the lungs. Peripheral a ...
... spinal motor neurons controlling respiratory muscles. Cardiovascular sympathetic and vagal activities have characteristic discharges that are patterned by respiratory activity. This patterning ensures ventilation– perfusion matching for optimal respiratory gas exchange within the lungs. Peripheral a ...
SOM
... • Neural networks for unsupervised learning attempt to discover special patterns from available data without using external help (i.e. RISK FUNCTION). – There is no information about the desired class (or output ) d of an example x. So only x is given. – Self Organising Maps (SOM) are neural network ...
... • Neural networks for unsupervised learning attempt to discover special patterns from available data without using external help (i.e. RISK FUNCTION). – There is no information about the desired class (or output ) d of an example x. So only x is given. – Self Organising Maps (SOM) are neural network ...
Laminar Selectivity of the Cholinergic Suppression of Synaptic
... in both layers during the same perfusion in each slice. Carbachol produced a significantly stronger suppression of stimulus-evoked EPSPs in s. rad than in s. I-m at all concentrations greater than 1 FM. At 100 PM, EPSP initial slopes were suppressed by 89.1 * 3.0% in s. rad, but only by 40.1 + 4.1% ...
... in both layers during the same perfusion in each slice. Carbachol produced a significantly stronger suppression of stimulus-evoked EPSPs in s. rad than in s. I-m at all concentrations greater than 1 FM. At 100 PM, EPSP initial slopes were suppressed by 89.1 * 3.0% in s. rad, but only by 40.1 + 4.1% ...
Simulating Populations of Neurons - Leeds VLE
... Understanding the brain is a recent fascination in modern computing. We have come to realise that the brain is the most advanced computational tool that we know of, to be able to replicate neuronal processes could vastly improve current computational techniques. However, the more we understand the m ...
... Understanding the brain is a recent fascination in modern computing. We have come to realise that the brain is the most advanced computational tool that we know of, to be able to replicate neuronal processes could vastly improve current computational techniques. However, the more we understand the m ...
Neurons in red nucleus and primary motor cortex exhibit similar
... 2012, 2014; Omrani et al., 2013). The fact that these context dependent responses occur during long, but not short latency responses is significant because it suggests that they are generated supraspinally. Supraspinal involvement in feedback control of volitional movement is also supported by elect ...
... 2012, 2014; Omrani et al., 2013). The fact that these context dependent responses occur during long, but not short latency responses is significant because it suggests that they are generated supraspinally. Supraspinal involvement in feedback control of volitional movement is also supported by elect ...
Where do mirror neurons come from?
... A characteristic of an organism, C, is an adaptation for a particular function, F, if C evolved because it helped organisms to do F (Sober, 2008; Williams, 1966). Therefore, the hypothesis that mirror neurons (C) are an adaptation for action understanding (F) concerns the origins, rather than the cu ...
... A characteristic of an organism, C, is an adaptation for a particular function, F, if C evolved because it helped organisms to do F (Sober, 2008; Williams, 1966). Therefore, the hypothesis that mirror neurons (C) are an adaptation for action understanding (F) concerns the origins, rather than the cu ...
Axon Initiation and Growth Cone Turning on Bound Protein Gradients Cellular/Molecular Junyu Mai,
... Berkeley, and 3Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 ...
... Berkeley, and 3Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 ...
Rostral Fastigial Nucleus Activity in the Alert Monkey During Three
... movements from rostral FN. Seated monkeys were rotated sinusoidally around a horizontal earth-fixed axis (vertical stimulation) at different orientations 157 apart (including roll, pitch, vertical canal plane and intermediate planes). In addition, sinusoidal rotations around an earth-vertical axis ( ...
... movements from rostral FN. Seated monkeys were rotated sinusoidally around a horizontal earth-fixed axis (vertical stimulation) at different orientations 157 apart (including roll, pitch, vertical canal plane and intermediate planes). In addition, sinusoidal rotations around an earth-vertical axis ( ...
nervous system physiology 4
... interaction of the cross-bridges from the myosin filaments with the actin filaments), causing them to slide alongside each other, which is the contractile process. Energy (ATP) is needed for the contractile process to proceed. After a fraction of a second, Ca2+ are pumped back into SR by a Ca2+-memb ...
... interaction of the cross-bridges from the myosin filaments with the actin filaments), causing them to slide alongside each other, which is the contractile process. Energy (ATP) is needed for the contractile process to proceed. After a fraction of a second, Ca2+ are pumped back into SR by a Ca2+-memb ...
Biophysical Properties and Responses to Neurotransmitters of
... Downloaded from http://jn.physiology.org/ by 10.220.32.246 on April 28, 2017 ...
... Downloaded from http://jn.physiology.org/ by 10.220.32.246 on April 28, 2017 ...
The role of spiking nonlinearity in contrast gain control
... The obtained ropt increases with saturation g (see Fig. 2e). It also increases slightly with an increase in threshold h (Fig. 2f). This might provide a mechanism and rules for a neuron to adjust its transfer function and gain tuning curve according to the statistical context of the input signals. Ho ...
... The obtained ropt increases with saturation g (see Fig. 2e). It also increases slightly with an increase in threshold h (Fig. 2f). This might provide a mechanism and rules for a neuron to adjust its transfer function and gain tuning curve according to the statistical context of the input signals. Ho ...
Optophysiological analysis of associational circuits in the olfactory
... Price, 1983b; Piredda and Gale, 1985; Behan and Haberly, 1999; Ekstrand et al., 2001; Neville and Haberly, 2004), but information at the level of cellular connectivity remains scarce (Franks and Isaacson, 2005; Wiegand et al., 2011). Modern molecular biological and viral techniques promise to yield ...
... Price, 1983b; Piredda and Gale, 1985; Behan and Haberly, 1999; Ekstrand et al., 2001; Neville and Haberly, 2004), but information at the level of cellular connectivity remains scarce (Franks and Isaacson, 2005; Wiegand et al., 2011). Modern molecular biological and viral techniques promise to yield ...
Action recognition in the premotor cortex
... 'grasping' mirror neurons. Some grasping mirror neurons stopped firing almost immediately as the hand grabbed the object, others continued to discharge for a while after the end of the action. An example of a grasping mirror neuron is shown in Fig. 1. Each trial started with the stimulus presentatio ...
... 'grasping' mirror neurons. Some grasping mirror neurons stopped firing almost immediately as the hand grabbed the object, others continued to discharge for a while after the end of the action. An example of a grasping mirror neuron is shown in Fig. 1. Each trial started with the stimulus presentatio ...
GLIA: LISTENING AND TALKING TO THE SYNAPSE
... have indicated that passive diffusion of Ins(1,4,5)P3 would not be sufficient by itself to account for the spread of the Ca2+ wave. Therefore, some form of regeneration of the source of Ins(1,4,5)P3 would be required to explain it35,37. Although the partially regenerative nature of the signal could ...
... have indicated that passive diffusion of Ins(1,4,5)P3 would not be sufficient by itself to account for the spread of the Ca2+ wave. Therefore, some form of regeneration of the source of Ins(1,4,5)P3 would be required to explain it35,37. Although the partially regenerative nature of the signal could ...
“Congruent” and “Opposite” Neurons: Sisters for Multisensory
... the responses of opposite neurons hardly vary when a single cue is replaced by two congruent cues (i.e., no cue integration behavior), whereas their responses increase significantly when the disparity between visual and vestibular cues increases [11], indicating that opposite neurons may serve to ex ...
... the responses of opposite neurons hardly vary when a single cue is replaced by two congruent cues (i.e., no cue integration behavior), whereas their responses increase significantly when the disparity between visual and vestibular cues increases [11], indicating that opposite neurons may serve to ex ...
Contextual modulation and stimulus selectivity in extrastriate cortex
... never still (Otero-Millan et al., 2008), and objects are typically stationary (Stocker & Simoncelli, 2006), most motion encountered by the visual system is due to displacement of the eye in space, either through saccades, smooth pursuit, head rotation, or navigation. The resulting optic flow stimuli ...
... never still (Otero-Millan et al., 2008), and objects are typically stationary (Stocker & Simoncelli, 2006), most motion encountered by the visual system is due to displacement of the eye in space, either through saccades, smooth pursuit, head rotation, or navigation. The resulting optic flow stimuli ...
Outputs of Radula Mechanoafferent Neurons in Aplysia are
... generate behavior. A form of sensory modulation was investigated in the Aplysia feeding system at the level of a radula mechanoafferent neuron (B21) that provides chemical synaptic input to a group of motor neurons (B8a/b, B15) that control closure and retraction movements of the radula, a food gras ...
... generate behavior. A form of sensory modulation was investigated in the Aplysia feeding system at the level of a radula mechanoafferent neuron (B21) that provides chemical synaptic input to a group of motor neurons (B8a/b, B15) that control closure and retraction movements of the radula, a food gras ...
On the Role of the Pontine Brainstem in Vocal Pattern Generation: A
... pair of electrodes was implanted at a new position. Neuronal activity was recorded during all call types uttered. Quantitative data analysis was done for two highly frequency-modulated call types with a rhythmical character (trill, cackle), a high-pitched (peep), and a low-pitched nonrhythmic call ( ...
... pair of electrodes was implanted at a new position. Neuronal activity was recorded during all call types uttered. Quantitative data analysis was done for two highly frequency-modulated call types with a rhythmical character (trill, cackle), a high-pitched (peep), and a low-pitched nonrhythmic call ( ...
Dynamics and Synchronization of Motifs of Neuronal Populations in the Presence
... cortex (striate), up to extrastriate cortical cells. In the first layer, the receptive field of a photoreceptor neuron corresponds to the region in which light alters the firing response of that cell. For the ganglion cells in the retina, the receptive field encompasses the sensitive areas of their ...
... cortex (striate), up to extrastriate cortical cells. In the first layer, the receptive field of a photoreceptor neuron corresponds to the region in which light alters the firing response of that cell. For the ganglion cells in the retina, the receptive field encompasses the sensitive areas of their ...
Nonsynaptic plasticity
Nonsynaptic plasticity is a form of neuroplasticity that involves modification of ion channel function in the axon, dendrites, and cell body that results in specific changes in the integration of excitatory postsynaptic potentials (EPSPs) and inhibitory postsynaptic potentials (IPSPs). Nonsynaptic plasticity is a modification of the intrinsic excitability of the neuron. It interacts with synaptic plasticity, but it is considered a separate entity from synaptic plasticity. Intrinsic modification of the electrical properties of neurons plays a role in many aspects of plasticity from homeostatic plasticity to learning and memory itself. Nonsynaptic plasticity affects synaptic integration, subthreshold propagation, spike generation, and other fundamental mechanisms of neurons at the cellular level. These individual neuronal alterations can result in changes in higher brain function, especially learning and memory. However, as an emerging field in neuroscience, much of the knowledge about nonsynaptic plasticity is uncertain and still requires further investigation to better define its role in brain function and behavior.