An Optogenetic Approach to Understanding the Neural Circuits of Fear
... known to be activated during specific time periods of fear conditioning (example, CS or US periods), but in most cases, their temporally limited, functional role in behavior and neural processing is unknown. In addition, within specific areas of the fear circuit, there are neuronal subpopulations (s ...
... known to be activated during specific time periods of fear conditioning (example, CS or US periods), but in most cases, their temporally limited, functional role in behavior and neural processing is unknown. In addition, within specific areas of the fear circuit, there are neuronal subpopulations (s ...
The Plasticity of Denervated and Reinnervated Laryngeal
... Time course of changes in muscle fiber diameter for the posterior cricoarytenoid (PCA) and the thyroarytenoid (TA) muscles. Consistent with the muscle-weight data shown in Figure 1, the fiber diameter of the denervated PCA and TA muscles was significantly smaller than that of the control group at th ...
... Time course of changes in muscle fiber diameter for the posterior cricoarytenoid (PCA) and the thyroarytenoid (TA) muscles. Consistent with the muscle-weight data shown in Figure 1, the fiber diameter of the denervated PCA and TA muscles was significantly smaller than that of the control group at th ...
Axons break in animals lacking β-spectrin
... The proximal end has initiated a new growth cone (open arrowhead). At 48 h, the secondary growth has reached the dorsal cord, albeit by an aberrant posterior route (open arrowheads). (The new dorsal and posterior neuron is DVB [asterisks], which arises postembryonically and sends an axon ventrally t ...
... The proximal end has initiated a new growth cone (open arrowhead). At 48 h, the secondary growth has reached the dorsal cord, albeit by an aberrant posterior route (open arrowheads). (The new dorsal and posterior neuron is DVB [asterisks], which arises postembryonically and sends an axon ventrally t ...
- Orange Coast College
... Preganglionic fibers branch to synapse with # of postganglionic neurons. Convergence: Postganglionic neuron receives synaptic input from large # of preganglionic fibers. ...
... Preganglionic fibers branch to synapse with # of postganglionic neurons. Convergence: Postganglionic neuron receives synaptic input from large # of preganglionic fibers. ...
PREFERENTIAL POTENTIATION OF WEAKER INPUTS TO PRIMARY
... Kingston, Ontario, Canada (March, 2009) ...
... Kingston, Ontario, Canada (March, 2009) ...
NEUROTRANSMISSION
... pieces are shaped like neurons? The goal is to be the first to get an important piece of information to the brain.” Jay chimes in, “At the beginning of the game, each player finds out, from a booklet, what that piece of information is. Mine is that I’m being chased by a hungry lion. I need to let my ...
... pieces are shaped like neurons? The goal is to be the first to get an important piece of information to the brain.” Jay chimes in, “At the beginning of the game, each player finds out, from a booklet, what that piece of information is. Mine is that I’m being chased by a hungry lion. I need to let my ...
Epistatic interaction of CREB1 and KCNJ6 on rumination and
... Regarding the neurocognitive background of rumination, clinical studies have shown that rumination can be regarded as a mediator between overgeneralization of memories — the tendency to retrieve autobiographical memories as categories rather than specific instances — and depression (Debeer et al., 2 ...
... Regarding the neurocognitive background of rumination, clinical studies have shown that rumination can be regarded as a mediator between overgeneralization of memories — the tendency to retrieve autobiographical memories as categories rather than specific instances — and depression (Debeer et al., 2 ...
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... mechanisms, Hebbian learning and lateral inhibition, but we further its optimality. The inter-layer developmental mechanisms specify how information between layers are passed and used, which enables both unsupervised and supervised learning to occur in the same network. Of course there are many othe ...
... mechanisms, Hebbian learning and lateral inhibition, but we further its optimality. The inter-layer developmental mechanisms specify how information between layers are passed and used, which enables both unsupervised and supervised learning to occur in the same network. Of course there are many othe ...
How is the stimulus represented in the nervous system?
... The problem comes in estimating P(v) and P(n) which may be difficult to do meaningfully, especially for natural stimuli. Thus we often work on the forward problem, estimating the response given an arbitrary stimulus, and postpone the reverse problem. There is another problem: what is the appropriate ...
... The problem comes in estimating P(v) and P(n) which may be difficult to do meaningfully, especially for natural stimuli. Thus we often work on the forward problem, estimating the response given an arbitrary stimulus, and postpone the reverse problem. There is another problem: what is the appropriate ...
Impaired associative learning in schizophrenia: behavioral and
... and prefrontal cortex in memory encoding and retrieval (Simons and Spiers 2003). Separate studies of behavioral pharmacology have identified molecular mechanisms for associative learning. Activity of the N-methyl-D-aspartate (NMDAR) receptor and its sub-units (NR1-2) in the hippocampus are specifica ...
... and prefrontal cortex in memory encoding and retrieval (Simons and Spiers 2003). Separate studies of behavioral pharmacology have identified molecular mechanisms for associative learning. Activity of the N-methyl-D-aspartate (NMDAR) receptor and its sub-units (NR1-2) in the hippocampus are specifica ...
Synchronization and coordination of sequences in two neural
... B: 共i兲 as other sensory organs, both statocysts are not exactly identical. However, the offset in the connection matrices cannot be too high for it would not lead to WLC; 共ii兲 different external signals 共here from the hunting neurons兲 can arrive on the two sensory receptors. Moreover, we are interes ...
... B: 共i兲 as other sensory organs, both statocysts are not exactly identical. However, the offset in the connection matrices cannot be too high for it would not lead to WLC; 共ii兲 different external signals 共here from the hunting neurons兲 can arrive on the two sensory receptors. Moreover, we are interes ...
Induction of c-fos Expression in Hypothalamic Magnocellular
... pressure and the injection of oxytocin intravenously (i.v.), respectively. Mammary gland responsiveness was checked with single injections of 0.25-l mU of oxytocin (Syntocinon, Sandoz Pharmaceuticals, UK). For cranial surgery, the rats were positioned in a stereotaxic frame with the dorsal surface o ...
... pressure and the injection of oxytocin intravenously (i.v.), respectively. Mammary gland responsiveness was checked with single injections of 0.25-l mU of oxytocin (Syntocinon, Sandoz Pharmaceuticals, UK). For cranial surgery, the rats were positioned in a stereotaxic frame with the dorsal surface o ...
Expectation of reward modulates cognitive signals in the basal ganglia
... model is therefore ideal for investigating the cognitive aspect of action or attention, but not the motivational aspect. Action is controlled by both cognition and motivation4,5, and motivational states vary considerably. The same action can lead to different reward outcomes in different behavioral ...
... model is therefore ideal for investigating the cognitive aspect of action or attention, but not the motivational aspect. Action is controlled by both cognition and motivation4,5, and motivational states vary considerably. The same action can lead to different reward outcomes in different behavioral ...
Fut u re N
... the probability that it will be retrieved again. Over time, this memory grows like a snowball rolling down a mountain or a malignant cancer spreading through the body. This growth occurs both within and across anatomical regions. Because the propensity for synaptic plasticity increases the risk for ...
... the probability that it will be retrieved again. Over time, this memory grows like a snowball rolling down a mountain or a malignant cancer spreading through the body. This growth occurs both within and across anatomical regions. Because the propensity for synaptic plasticity increases the risk for ...
Dorsal Column Nuclei Neurons Recorded in a Brain Stem–Spinal
... Dorsal column nuclei neurons recorded in a brain stem–spinal cord preparation: characteristics and their responses to dorsal root stimulation. J Neurophysiol 84: 1361–1368, 2000. Recordings were obtained from dorsal column nucleus (DCN) neurons in a neonatal rat brain stem—spinal cord preparation to ...
... Dorsal column nuclei neurons recorded in a brain stem–spinal cord preparation: characteristics and their responses to dorsal root stimulation. J Neurophysiol 84: 1361–1368, 2000. Recordings were obtained from dorsal column nucleus (DCN) neurons in a neonatal rat brain stem—spinal cord preparation to ...
Neuromodulation and cortical function: BEHAVIOURAL BRAIN
... activated by aEerent or intrinsic fibers release GAB A, which causes fast inhibitory potentials mediated by GABA, receptors [ 2241. (These potentials are hyperpolarizing only when membrane potential is depolarized above the chloride reversal potential). C: intrinsic fiber synapses arising from other ...
... activated by aEerent or intrinsic fibers release GAB A, which causes fast inhibitory potentials mediated by GABA, receptors [ 2241. (These potentials are hyperpolarizing only when membrane potential is depolarized above the chloride reversal potential). C: intrinsic fiber synapses arising from other ...
Sensorimotor Neural Plasticity following Hand Transplantation
... same region becomes responsive to inputs originated in other body parts with adjacent cortical representations" (Navarro et al., 2007). Chen et al., (2002) reported that MEG revealed that there are rapid changes in the somatosensory cortex following deafferentation. Deafferentation is when the affer ...
... same region becomes responsive to inputs originated in other body parts with adjacent cortical representations" (Navarro et al., 2007). Chen et al., (2002) reported that MEG revealed that there are rapid changes in the somatosensory cortex following deafferentation. Deafferentation is when the affer ...
Communication as an emergent metaphor for neuronal operation
... well in this new paradigm and will show that its properties make it interesting from both the technological and brain modelling perspectives. In a recent paper [7], Selman et al. posed some challenge problems for Artificial Intelligence. In particular Rodney Brooks suggested revising the conventiona ...
... well in this new paradigm and will show that its properties make it interesting from both the technological and brain modelling perspectives. In a recent paper [7], Selman et al. posed some challenge problems for Artificial Intelligence. In particular Rodney Brooks suggested revising the conventiona ...
Document
... relationship with the latency in neuron firing (polysynaptic integration leading to response) ...
... relationship with the latency in neuron firing (polysynaptic integration leading to response) ...
2 Brain and Classical Neural Networks
... after it fired, of about 1–2 ms, independently of how large the amplitude of the depolarizing potential would be. This period is called the absolute refractory period of the neuron. Clearly, it sets an upper bound on the spike frequency of 500–1000/s. In the types of neurons that we will be intereste ...
... after it fired, of about 1–2 ms, independently of how large the amplitude of the depolarizing potential would be. This period is called the absolute refractory period of the neuron. Clearly, it sets an upper bound on the spike frequency of 500–1000/s. In the types of neurons that we will be intereste ...
An Energy Budget for Signaling in the Grey Matter of the Brain
... 4.4-fold at −70 mV at cerebellar synapses (Jahr and Stevens, 1990)). Taking an average value of 1, and noting that 10% of the charge influx is carried by Ca2+ rather than Na+ (Burnashev et al., 1995), this implies an entry of 180,000 Na+ and 10,000 Ca2+ per vesicle of glutamate released. Each Ca2+ i ...
... 4.4-fold at −70 mV at cerebellar synapses (Jahr and Stevens, 1990)). Taking an average value of 1, and noting that 10% of the charge influx is carried by Ca2+ rather than Na+ (Burnashev et al., 1995), this implies an entry of 180,000 Na+ and 10,000 Ca2+ per vesicle of glutamate released. Each Ca2+ i ...
Excitatory Cerebellar Nucleocortical Circuit Provides Internal
... MFs of these animals were found predominantly in regions negative for Zebrin II, including the trough of the lobule simplex (Figures 3A–3C). More specifically, we observed that 90.5% (±3.3%), 88.5% (±6.2%), and 93.7% (±2.8%) of the nucleocortical MF originating in the anterior IpN terminated in the ...
... MFs of these animals were found predominantly in regions negative for Zebrin II, including the trough of the lobule simplex (Figures 3A–3C). More specifically, we observed that 90.5% (±3.3%), 88.5% (±6.2%), and 93.7% (±2.8%) of the nucleocortical MF originating in the anterior IpN terminated in the ...
Encoding Information in Neuronal Activity
... a neuron will lose the precise time of arrival of individual spikes. The amount of postsynaptic depolarization will depend only on the number of spikes arriving at the neuron and the process of synaptic transmission of these spikes. Further, if the firing rate is a direct function of the level of de ...
... a neuron will lose the precise time of arrival of individual spikes. The amount of postsynaptic depolarization will depend only on the number of spikes arriving at the neuron and the process of synaptic transmission of these spikes. Further, if the firing rate is a direct function of the level of de ...
Frog Vision
... • The four tectal sheets of neurons essentially provide a recoding of the retinal image. • The retinal image is specified in terms of luminance at each receptor - this description is redundant and not useful to frog. • Tectal neurons recode each small region on retina in terms of 4 basic features or ...
... • The four tectal sheets of neurons essentially provide a recoding of the retinal image. • The retinal image is specified in terms of luminance at each receptor - this description is redundant and not useful to frog. • Tectal neurons recode each small region on retina in terms of 4 basic features or ...
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.