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... transmit information from one neuron to the next. The flow of information is unidirectional: The sending neuron is called the “presynaptic neuron”, the receiving neuron is called the “postsynaptic neuron”. Apart from the morphology, neurons also differ from other cells in that they are electrically ac ...
... transmit information from one neuron to the next. The flow of information is unidirectional: The sending neuron is called the “presynaptic neuron”, the receiving neuron is called the “postsynaptic neuron”. Apart from the morphology, neurons also differ from other cells in that they are electrically ac ...
The horizontal brain slice preparation: a novel approach for
... of connections between individual tectal neurons, probably because the connections exist across layers and so could not be identified using the whole brain or in vivo preparation. In addition to being able to record from neurons across layers, this horizontal brain slice preparation also provides di ...
... of connections between individual tectal neurons, probably because the connections exist across layers and so could not be identified using the whole brain or in vivo preparation. In addition to being able to record from neurons across layers, this horizontal brain slice preparation also provides di ...
Synaptic basis for intense thalamocortical activation of feedforward
... consequences of feedforward inhibition have been extensively considered12–14, little is known about the mechanisms of the strong interneuron activation that produces it. Obviously, understanding how both inhibitory and excitatory neurons in the neocortex respond to their principle external input is ...
... consequences of feedforward inhibition have been extensively considered12–14, little is known about the mechanisms of the strong interneuron activation that produces it. Obviously, understanding how both inhibitory and excitatory neurons in the neocortex respond to their principle external input is ...
1 Introduction to Behavioral Endocrinology
... When considering the dose, some investigators might be tempted to begin with high doses of a hormone just to be sure that they see an effect. Results from high doses, however, can be very misleading. A bell-shaped curve showing the relationship between a hormone and a behavior is frequently found in ...
... When considering the dose, some investigators might be tempted to begin with high doses of a hormone just to be sure that they see an effect. Results from high doses, however, can be very misleading. A bell-shaped curve showing the relationship between a hormone and a behavior is frequently found in ...
Synaptic energy efficiency in retinal processing
... whilst minimising the metabolic costs associated with synaptic transmission. Following Bell and Sejnowski (1997), Harpur (1997) and Olshausen and Field (1996), we quantify the information transmitted in terms of the sum squared reconstruction error. If the signal (the images) and the noise are Gauss ...
... whilst minimising the metabolic costs associated with synaptic transmission. Following Bell and Sejnowski (1997), Harpur (1997) and Olshausen and Field (1996), we quantify the information transmitted in terms of the sum squared reconstruction error. If the signal (the images) and the noise are Gauss ...
review_for_midterm_november_4_2015
... What is the endocrine system and how does it work? Be able to discuss specific glands, their location (be able to label them on a diagram-see page 998 in your text) and their functions (what hormones do they release and what do these hormones do). Be able to explain the difference between ster ...
... What is the endocrine system and how does it work? Be able to discuss specific glands, their location (be able to label them on a diagram-see page 998 in your text) and their functions (what hormones do they release and what do these hormones do). Be able to explain the difference between ster ...
Neuronal polarity: an evolutionary perspective
... In vertebrates, directional signaling of neurons is most often accomplished by specialization of neuronal processes into axons and dendrites, with axons as the output side of the cell and dendrites the input side. This specialization is termed neuronal polarity. In assembling the functional circuit ...
... In vertebrates, directional signaling of neurons is most often accomplished by specialization of neuronal processes into axons and dendrites, with axons as the output side of the cell and dendrites the input side. This specialization is termed neuronal polarity. In assembling the functional circuit ...
vesicle
... Neurons form networks through which nerve impulses travel. Each neuron receives as many as 15,000 connections from other neurons. Neurons do not touch each other; they have contact points called synapses. A neuron transports its information by way of a nerve impulse. When a nerve impulse arrives at ...
... Neurons form networks through which nerve impulses travel. Each neuron receives as many as 15,000 connections from other neurons. Neurons do not touch each other; they have contact points called synapses. A neuron transports its information by way of a nerve impulse. When a nerve impulse arrives at ...
A Role for the Basal Forebrain Cholinergic System in Estrogen
... ad libitum access to food and water. All rats were bilaterally ovariectomized under ketamine (85 mg/kg)/xylazine (13 mg/kg) anesthesia using aseptic procedures. On the third day after surgery, rats were injected subcutaneously with either 10 g of 17-estradiol benzoate (E) in 100 l of sesame oil o ...
... ad libitum access to food and water. All rats were bilaterally ovariectomized under ketamine (85 mg/kg)/xylazine (13 mg/kg) anesthesia using aseptic procedures. On the third day after surgery, rats were injected subcutaneously with either 10 g of 17-estradiol benzoate (E) in 100 l of sesame oil o ...
Transient information flow in a network of excitatory and inhibitory
... networks of neurons. A given neuron is functionally connected to only a relatively small fraction of the other neurons. The connection strength between neurons is not fixed, but is mediated by synapses that have their own dynamics [3,56,15,19,28,60]. Maass and colleagues have chosen to simulate netwo ...
... networks of neurons. A given neuron is functionally connected to only a relatively small fraction of the other neurons. The connection strength between neurons is not fixed, but is mediated by synapses that have their own dynamics [3,56,15,19,28,60]. Maass and colleagues have chosen to simulate netwo ...
Na /Ca2+ Exchanger Maintains Ionic Homeostasis in the
... Methods—Extracellular field potentials and whole-cell patch clamp recordings were obtained from rat corticostriatal brain-slice preparations in the peri-infarct area 24 hours after the permanent middle cerebral artery occlusion. Ischemia was induced in rats by permanents middle cerebral artery occlu ...
... Methods—Extracellular field potentials and whole-cell patch clamp recordings were obtained from rat corticostriatal brain-slice preparations in the peri-infarct area 24 hours after the permanent middle cerebral artery occlusion. Ischemia was induced in rats by permanents middle cerebral artery occlu ...
PDF
... at two distant neurons. We hold N = 100 and t = 1 fixed and investigate the behaviour of U by modifying the length constant p and the cut off R for several choices of the gain g and threshold K. Figure 2 shows a typical example, a plot of the propagation velocity against the inverse of the synaptic ...
... at two distant neurons. We hold N = 100 and t = 1 fixed and investigate the behaviour of U by modifying the length constant p and the cut off R for several choices of the gain g and threshold K. Figure 2 shows a typical example, a plot of the propagation velocity against the inverse of the synaptic ...
PDF
... intact organism. However, although adequate in many cases, this approach may lead to misinterpretation in many others. The concept of the excitatory action of GABA at early postnatal stages of development provides a particular example of correct observations performed in vitro which may not apply to ...
... intact organism. However, although adequate in many cases, this approach may lead to misinterpretation in many others. The concept of the excitatory action of GABA at early postnatal stages of development provides a particular example of correct observations performed in vitro which may not apply to ...
SA1 Functional implications of RyR-DHPR relationships in skeletal
... that control of SR content depends on the effects of Ca release on surface membrane Ca fluxes. Specifically an increase of SR content increases SR Ca release and this (1) increases Ca efflux from the cell on Na-Ca exchange and (2) decreases Ca entry into the cell via the L-type Ca current. Both of t ...
... that control of SR content depends on the effects of Ca release on surface membrane Ca fluxes. Specifically an increase of SR content increases SR Ca release and this (1) increases Ca efflux from the cell on Na-Ca exchange and (2) decreases Ca entry into the cell via the L-type Ca current. Both of t ...
Computational models of reinforcement learning
... and dynamic programming. It refers to the trial-and-error learning of the set of actions an agent must take to maximize future rewards or minimize punishments (Sutton and Barto 1998). RL is fundamental to the psychological and neuroscientific studies of reinforcement and conditioning, and to the neu ...
... and dynamic programming. It refers to the trial-and-error learning of the set of actions an agent must take to maximize future rewards or minimize punishments (Sutton and Barto 1998). RL is fundamental to the psychological and neuroscientific studies of reinforcement and conditioning, and to the neu ...
Substrate Stiffness and Adhesivity Influence Neuron Axonal Growth
... conditions of a given trial. As directed for this cell line, they are kept in an incubator at 36-38 C and 5% CO2, and supplied with appropriately supplemented Neurobasal Medium (Invitrogen), as directed by the instructions included by Invitrogen. Specifically, Neurobasal Media is supplemented with 2 ...
... conditions of a given trial. As directed for this cell line, they are kept in an incubator at 36-38 C and 5% CO2, and supplied with appropriately supplemented Neurobasal Medium (Invitrogen), as directed by the instructions included by Invitrogen. Specifically, Neurobasal Media is supplemented with 2 ...
Functional Connectivity during Surround Suppression in
... sensory neurons. For neurons of the visual cortex, it occurs when a visual stimulus extends beyond a neuron's classical receptive field, reducing the neuron's firing rate. While several studies have been attributing the suppression effect on horizontal, long-range lateral or feedback connections, th ...
... sensory neurons. For neurons of the visual cortex, it occurs when a visual stimulus extends beyond a neuron's classical receptive field, reducing the neuron's firing rate. While several studies have been attributing the suppression effect on horizontal, long-range lateral or feedback connections, th ...
BCM Theory
... background input from MFs. This disconnection of the CFs removed any variability in PCs, such as the complex spikes, making it possible to lump the activity of the PC population together. We also verified the equivalence of the two models by following the trajectory of the PC population output and ...
... background input from MFs. This disconnection of the CFs removed any variability in PCs, such as the complex spikes, making it possible to lump the activity of the PC population together. We also verified the equivalence of the two models by following the trajectory of the PC population output and ...
Synaptic reverberation underlying mnemonic persistent activity
... excitatory connections in a recurrent network are sufficiently strong. It is only recently, beginning with the work by Amit and colleagues, that attractor network models have been implemented with realistic models of cortical neurons and synapses22–27. Figure 2 illustrates the biophysics of an attra ...
... excitatory connections in a recurrent network are sufficiently strong. It is only recently, beginning with the work by Amit and colleagues, that attractor network models have been implemented with realistic models of cortical neurons and synapses22–27. Figure 2 illustrates the biophysics of an attra ...
6.034 Neural Net Notes
... That is, you computed change in a neuron’s w, in every layer, by multiplying α times the neuron’s input times its δ. The δ is determined for all but the final layer in terms of the neuron’s output and all the weights that connect that output to neurons in the layer to the right and the δs associated ...
... That is, you computed change in a neuron’s w, in every layer, by multiplying α times the neuron’s input times its δ. The δ is determined for all but the final layer in terms of the neuron’s output and all the weights that connect that output to neurons in the layer to the right and the δs associated ...
RH Ettinger - Test Bank 1
... 30. Which of the following is NOT a criterion for a substance to meet the definition of a neurotransmitter? a. It must be synthesized and stored in the presynaptic neuron. b. It must cause a postsynaptic effect after it interacts with a receptor. c. It must be taken up intact by the transmitting ne ...
... 30. Which of the following is NOT a criterion for a substance to meet the definition of a neurotransmitter? a. It must be synthesized and stored in the presynaptic neuron. b. It must cause a postsynaptic effect after it interacts with a receptor. c. It must be taken up intact by the transmitting ne ...
Membrane Potential Fluctuations in Neural Integrator
... neurons have branching axon segments called collaterals and a single neuron can provide input for multiple target neurons. While information generally flows from the dendrite to the soma to the axon to the target dendrite, examples exist for direct dendro-dendritic [51] or dendro-axonal connections ...
... neurons have branching axon segments called collaterals and a single neuron can provide input for multiple target neurons. While information generally flows from the dendrite to the soma to the axon to the target dendrite, examples exist for direct dendro-dendritic [51] or dendro-axonal connections ...
Chemical synapse
Chemical synapses are specialized junctions through which neurons signal to each other and to non-neuronal cells such as those in muscles or glands. Chemical synapses allow neurons to form circuits within the central nervous system. They are crucial to the biological computations that underlie perception and thought. They allow the nervous system to connect to and control other systems of the body.At a chemical synapse, one neuron releases neurotransmitter molecules into a small space (the synaptic cleft) that is adjacent to another neuron. The neurotransmitters are kept within small sacs called vesicles, and are released into the synaptic cleft by exocytosis. These molecules then bind to receptors on the postsynaptic cell's side of the synaptic cleft. Finally, the neurotransmitters must be cleared from the synapse through one of several potential mechanisms including enzymatic degradation or re-uptake by specific transporters either on the presynaptic cell or possibly by neuroglia to terminate the action of the transmitter.The adult human brain is estimated to contain from 1014 to 5 × 1014 (100–500 trillion) synapses. Every cubic millimeter of cerebral cortex contains roughly a billion (short scale, i.e. 109) of them.The word ""synapse"" comes from ""synaptein"", which Sir Charles Scott Sherrington and colleagues coined from the Greek ""syn-"" (""together"") and ""haptein"" (""to clasp""). Chemical synapses are not the only type of biological synapse: electrical and immunological synapses also exist. Without a qualifier, however, ""synapse"" commonly means chemical synapse.