Synaptic Depression and the Temporal Response Characteristics of
... highly simplified, the synaptic dynamics is modeled quite accurately using a mathematical description that fits experimental data (Abbott et al., 1997; Varela et al., 1997). Although a number of mechanisms may contribute to temporal nonlinearities in cortical responses, we focus rather exclusively o ...
... highly simplified, the synaptic dynamics is modeled quite accurately using a mathematical description that fits experimental data (Abbott et al., 1997; Varela et al., 1997). Although a number of mechanisms may contribute to temporal nonlinearities in cortical responses, we focus rather exclusively o ...
The contribution of intrinsic membrane dynamics to fast network
... ⬎100 Hz and can be as high as 300 Hz, whereas single cells fire irregularly and at a much lower rate than the population frequency. It was then shown that in a two-population network of inhibitory and excitatory LIF neurons the population frequency depends both on the time constants of excitatory an ...
... ⬎100 Hz and can be as high as 300 Hz, whereas single cells fire irregularly and at a much lower rate than the population frequency. It was then shown that in a two-population network of inhibitory and excitatory LIF neurons the population frequency depends both on the time constants of excitatory an ...
How Reliably Does a Neuron in the Visual Motion Pathway of fhe Fly
... at least to a large extent, by the animal itself. Hence, in order to assess the functional significance of neuronal noise, the noise has to be related to the stimulus-induced responses as are elicited by behaviourally relevant stimuli, i.e. stimuli that are similar to those experienced by a n animal ...
... at least to a large extent, by the animal itself. Hence, in order to assess the functional significance of neuronal noise, the noise has to be related to the stimulus-induced responses as are elicited by behaviourally relevant stimuli, i.e. stimuli that are similar to those experienced by a n animal ...
Solving the Distal Reward Problem through
... regular spiking type and 20% inhibitory neurons of the fast spiking type (Connors and Gutnick 1990), representing the layer 2/3 part of a cortical minicolumn. Neurons are randomly connected with 10% probability so that there are 100 synapses per averaged neuron. The connections, combined with the ra ...
... regular spiking type and 20% inhibitory neurons of the fast spiking type (Connors and Gutnick 1990), representing the layer 2/3 part of a cortical minicolumn. Neurons are randomly connected with 10% probability so that there are 100 synapses per averaged neuron. The connections, combined with the ra ...
State-Dependent Computation Using Coupled Recurrent Networks
... network are usually organized as a simple linear map in which each unit receives excitatory inputs from its neighboring units as well as an inhibitory input that is proportional to the total activity of all units (Dayan & Abbott, 2001; Douglas & Martin, 2007). We use the term map to indicate that th ...
... network are usually organized as a simple linear map in which each unit receives excitatory inputs from its neighboring units as well as an inhibitory input that is proportional to the total activity of all units (Dayan & Abbott, 2001; Douglas & Martin, 2007). We use the term map to indicate that th ...
and Third-Order Neurons of Cockroach Ocelli
... in second-order neurons by either an extrinsic current or a sinusoidally modulated light. The synapse had a low-pass filter characteristic with a cutoff frequency of 2 5 - 3 0 Hz, which passed most presynaptic signals. The synapse operated at an exponentially rising part o f the overall sigmoidal in ...
... in second-order neurons by either an extrinsic current or a sinusoidally modulated light. The synapse had a low-pass filter characteristic with a cutoff frequency of 2 5 - 3 0 Hz, which passed most presynaptic signals. The synapse operated at an exponentially rising part o f the overall sigmoidal in ...
Nancy A. O`Rourke Nicholas C. Weiler Kristina D
... require the pooling of heterogeneous synaptic populations, and thus do not inform us about differences in the molecular composition of single synapses. Thus far, only a few proteomic studies have analyzed different synapse types or synapses from different brain regions. For example, a study of PSDs ...
... require the pooling of heterogeneous synaptic populations, and thus do not inform us about differences in the molecular composition of single synapses. Thus far, only a few proteomic studies have analyzed different synapse types or synapses from different brain regions. For example, a study of PSDs ...
3-Morpholinylsydnonimine Inhibits Glutamatergic Transmission in
... In a previous study, we found that the regulation of sympathetic vasomotor outflow by the endogenous NO is determined by a balance between sympathoexcitation and sympathoinhibition induced by the tonically active nNOS and iNOS (Chan et al., 2001). More importantly, we showed that the prevalence of n ...
... In a previous study, we found that the regulation of sympathetic vasomotor outflow by the endogenous NO is determined by a balance between sympathoexcitation and sympathoinhibition induced by the tonically active nNOS and iNOS (Chan et al., 2001). More importantly, we showed that the prevalence of n ...
Glycolytic Enzymes Localize to Synapses under Energy Stress to
... ATP is predominantly produced by either glycolysis or oxidative phosphorylation. But not all ATP is created equal, and these two sources contribute differentially to various metabolic processes (Pfeiffer et al., 2001). Oxidative phosphorylation, which is mediated by the mitochondria, is an efficient ...
... ATP is predominantly produced by either glycolysis or oxidative phosphorylation. But not all ATP is created equal, and these two sources contribute differentially to various metabolic processes (Pfeiffer et al., 2001). Oxidative phosphorylation, which is mediated by the mitochondria, is an efficient ...
PDF file - Izhikevich
... are presented in the top of Figure 2, right. The lower part of Figure 2 shows membrane potential responses (variable v(t)) when pulses of DC current (variable I) are applied. Despite the simplicity of the model, it reproduces a number of different firing patterns that resemble those observed in the ...
... are presented in the top of Figure 2, right. The lower part of Figure 2 shows membrane potential responses (variable v(t)) when pulses of DC current (variable I) are applied. Despite the simplicity of the model, it reproduces a number of different firing patterns that resemble those observed in the ...
TESIS DOCTORAL Dynamics and Synchronization in Neuronal Models
... by a model. A good model should contain enough details in order to describe the principal biophysical aspects but must remain simple enough to provide a clear interpretation of the results. This thesis is mainly devoted to the modeling and simulations on neuronal systems with emphasis in different a ...
... by a model. A good model should contain enough details in order to describe the principal biophysical aspects but must remain simple enough to provide a clear interpretation of the results. This thesis is mainly devoted to the modeling and simulations on neuronal systems with emphasis in different a ...
Lecture notes Neural Computation
... of course), where the connection to next neurons in the circuit are formed, Fig. 1.4. The action ...
... of course), where the connection to next neurons in the circuit are formed, Fig. 1.4. The action ...
Spike-timing-dependent plasticity: common themes
... part of the review, we consider some of the differences in STDP models and their functional consequences. These recent studies on STDP come in the backdrop of a large body of work based on Hebb’s postulate of learning (Sejnowski 1999). Hebb’s original postulate is consistent with the observed tempora ...
... part of the review, we consider some of the differences in STDP models and their functional consequences. These recent studies on STDP come in the backdrop of a large body of work based on Hebb’s postulate of learning (Sejnowski 1999). Hebb’s original postulate is consistent with the observed tempora ...
neural_networks
... quantitative aspect of the total pattern we associate with that individual. A feature can be an axis in a higher dimensional geometric space. Qualitative features can also be valued, as zero or one, for the absence or presence of a feature (e.g., ‘has a driver’s license’) We will only use non-negati ...
... quantitative aspect of the total pattern we associate with that individual. A feature can be an axis in a higher dimensional geometric space. Qualitative features can also be valued, as zero or one, for the absence or presence of a feature (e.g., ‘has a driver’s license’) We will only use non-negati ...
Adaptation of Firing Rate and Spike
... (⬃500 –2000 Hz) (Rubel and Parks, 1975). Cells were accepted for analysis if the resting membrane potential was more negative than ⫺55 mV. NM neurons increase firing rate in response to noisy depolarizing current To investigate the possibility of spike frequency adaptation in NM neurons, voltage res ...
... (⬃500 –2000 Hz) (Rubel and Parks, 1975). Cells were accepted for analysis if the resting membrane potential was more negative than ⫺55 mV. NM neurons increase firing rate in response to noisy depolarizing current To investigate the possibility of spike frequency adaptation in NM neurons, voltage res ...
How Do Short-Term Changes at Synapses Fine
... information processing at these synapses. In this review, we discuss recent findings that address the functional role of STP in a number of neural systems. The described work examines both how complex neuronal activity affects the short-term state of synapses, as well as how this changed state affec ...
... information processing at these synapses. In this review, we discuss recent findings that address the functional role of STP in a number of neural systems. The described work examines both how complex neuronal activity affects the short-term state of synapses, as well as how this changed state affec ...
Contacts among non-sister dendritic branches at
... self-assembled neuronal networks in culture. We focused on dendrites as they were easier to quantify than axons, and attempted to identify characteristics along their structures and their contacts. We first defined two basic structures ...
... self-assembled neuronal networks in culture. We focused on dendrites as they were easier to quantify than axons, and attempted to identify characteristics along their structures and their contacts. We first defined two basic structures ...
MMNeuropharm2011
... 100 to 500 trillion synapses. The word “synapse” comes from the Greek “syn-” (“together”) and “haptein” (“to clasp”), coined by Sherrington in the late 19th century. In the CNS most synapses are chemical: the presynaptic neuron releases a neurotransmitter into the synaptic cleft that interacts with ...
... 100 to 500 trillion synapses. The word “synapse” comes from the Greek “syn-” (“together”) and “haptein” (“to clasp”), coined by Sherrington in the late 19th century. In the CNS most synapses are chemical: the presynaptic neuron releases a neurotransmitter into the synaptic cleft that interacts with ...
Event-Driven Simulation Scheme for Spiking Neural Networks Using
... and reordered (Reutimann et al., 2003; Makino, 2003). However, treating each spike as a fully arbitrary event leads to the event data structure’s becoming larger than necessary, because the order of spike emission by a given neuron is always known (it is defined in the interconnection list). We have ...
... and reordered (Reutimann et al., 2003; Makino, 2003). However, treating each spike as a fully arbitrary event leads to the event data structure’s becoming larger than necessary, because the order of spike emission by a given neuron is always known (it is defined in the interconnection list). We have ...
Print this article - University of Toronto Journal of Undergraduate Life
... periods of levodopa exposure [19, 24]. In addition to experimental investigations, numerous observational studies have shown that the severity and the duration of PD, the duration of levodopa therapy and high initial dose of levodopa are major risk factors associated with LIDs [20, 25, 26]. All toge ...
... periods of levodopa exposure [19, 24]. In addition to experimental investigations, numerous observational studies have shown that the severity and the duration of PD, the duration of levodopa therapy and high initial dose of levodopa are major risk factors associated with LIDs [20, 25, 26]. All toge ...
Functional Clustering Drives Encoding Improvement in a
... invasive in vivo observation of rapid sensory circuit development, from differentiation [22] to mature neurons driving behavioral responses [23]. Studies in the developing brain have described mechanisms controlling large-scale circuit patterning [24], finescale morphogenesis [21], and rules by whic ...
... invasive in vivo observation of rapid sensory circuit development, from differentiation [22] to mature neurons driving behavioral responses [23]. Studies in the developing brain have described mechanisms controlling large-scale circuit patterning [24], finescale morphogenesis [21], and rules by whic ...
the electron microscopic localization of
... extracellular spaces of considerable extent. These spaces contribute to the large "inulin space" of 18.6 per cent (Treherne, 1962 a): this total extracellular phase is very large compared with that of the vertebrate (Horstmann and Meves, 1959; et al., 1962) or leech (Coggeshall and Fawcett, 1964) ce ...
... extracellular spaces of considerable extent. These spaces contribute to the large "inulin space" of 18.6 per cent (Treherne, 1962 a): this total extracellular phase is very large compared with that of the vertebrate (Horstmann and Meves, 1959; et al., 1962) or leech (Coggeshall and Fawcett, 1964) ce ...
Molecular Basis for Induction of Ocular Dominance
... visual cortex. These data are reproduced from Wiesel and Hubel (1963). (A,B) Evoked potentials recorded from striate cortex in response to a brief light flash. At about the time of natural eye opening, this kitten had one eye covered with a translucent contact occluder that prevented patterned retin ...
... visual cortex. These data are reproduced from Wiesel and Hubel (1963). (A,B) Evoked potentials recorded from striate cortex in response to a brief light flash. At about the time of natural eye opening, this kitten had one eye covered with a translucent contact occluder that prevented patterned retin ...
Stochastic dynamics as a principle of brain function
... spiking noise. We show that the spiking noise is a significant contribution to the outcome that is reached, in that this noise is a factor in a network with a finite (i.e., limited) number of neurons. The spiking noise can be described as introducing statistical fluctuations into the finite-size system. ...
... spiking noise. We show that the spiking noise is a significant contribution to the outcome that is reached, in that this noise is a factor in a network with a finite (i.e., limited) number of neurons. The spiking noise can be described as introducing statistical fluctuations into the finite-size system. ...
Activity-dependent editing of neuromuscular synaptic connections
... synapse formation results in a coarse, but largely correct, pattern of connections between neurons and their targets, while the process of synaptic editing fine tunes these patterns so that they are well-suited to a lifetime of function. Synaptic editing is mediated by activity-dependent competitive ...
... synapse formation results in a coarse, but largely correct, pattern of connections between neurons and their targets, while the process of synaptic editing fine tunes these patterns so that they are well-suited to a lifetime of function. Synaptic editing is mediated by activity-dependent competitive ...