First, direct recordings from neurons in the cell groups that con

First, direct recordings from neurons in the cell groups that constitute the model show that their behavior is very close to what the model would predict. Recordings from VLPO neurons in both rats and mice show a sharp increase in firing just before or at the transition from waking to NREM sleep and DAPT datasheet a sharp decrease in firing just before the transition from NREM or REM to waking (Szymusiak et al., 1998 and Takahashi et al., 2009). Individual VLPO neurons differ somewhat in their onset of firing relative to the onset of NREM sleep, presumably because the individual cells differ slightly in

their inputs and responses. A neural network model of these neurons permitted the 2000 neurons on each side of the switch to have independent behavior, and this arrangement demonstrated a similar variability in the onset of firing compared to the actual state transition (Chou, 2003). A key feature in both the modeled neuronal behavior and the actual recordings

was the bistable nature of the firing, with abrupt transitions between rapid and slow firing right around the actual state transitions. Another interesting aspect of this system is the time relationship between changes in VLPO neuron firing and cortical activity. The onset of firing began about 200 msec before the EEG synchronization and did not reach a peak until 300 msec after the transition, whereas the fall in firing occurred over about 200 msec beginning ABT-263 just before the loss of EEG synchronization (Takahashi et al., 2009). The neural network model (Chou, 2003) predicts this behavior, and suggests that it underlies the hysteresis in the response

of the brain to homeostatic sleep drive, as suggested by Borbély and Achermann (1999). Thus, the threshold at which homeostatic not drive triggers sleep is higher than the threshold at which falling homeostatic sleep drive terminates sleep. This property may arise from a key aspect of the mutually inhibitory sleep-wake circuitry: sleep-promoting VLPO neurons can only be activated during wakefulness by stimuli that overcome their inhibition by wake-promoting neurons, but during sleep, when VLPO neurons are not inhibited by wake-promoting neurons, they can be activated by relatively weak stimuli such as low levels of homeostatic sleep drive. The activity of LC and TMN neurons also anticipates state transitions (Figure 3). The firing of LC neurons slows many seconds before sleep onset and then gradually increases 1–2 s prior to wake onset (Aston-Jones and Bloom, 1981 and Takahashi et al., 2010). The firing of TMN neurons also slows about 1 s prior to EEG signs of NREM sleep, but, unlike the LC, TMN neurons only start to fire about 1 s after wakefulness is established (Takahashi et al., 2006).

The membrane was blocked with PBS containing 5% skimmed milk (PBS

The membrane was blocked with PBS containing 5% skimmed milk (PBS-SM) for 1 h at 37 °C and incubated with cattle sera diluted at 1:100 with PBS-SM at 37 °C for 1 h. The membrane BLU9931 was washed three times with PBS-T for 5 min each and incubated with horseradish peroxidase-conjugated antibovine IgG (Sigma Chemicals, USA) diluted at 1:4000 with PBS-SM at 37 °C for 1 h. The reacting bands were revealed using 3,3′-tetrahydrochloride (DAB) and H2O2. Polystyrene 96-well microtiter plates (Polysorp Nunc, USA) were coated overnight at 4 °C

with 50 ng/well of recombinant protein NcSRS2 in 0.05-M carbonate–bicarbonate buffer (pH 9.6). The plates were then washed three times using 0.01-M PBS with 0.05% Tween 20 (PBS-T) and blocked using 0.01-M PBS with 5% nonfat milk at 37 °C for 1 h. After three washes with PBS-T, positive and negative control sera and serum samples, all in triplicate, were diluted at 1:100 in 0.01-M PBS with 5% nonfat milk and incubated at 37 °C for 1 h. After three washes, 100 μL/well of antibovine IgG conjugated to peroxidase (Sigma) diluted at 1:4000 in 0.01-M PBS with 5% nonfat milk were added, followed by incubation at 37 °C for 1 h. After another five washes, 100 μL of the substrate (o-phenylenediamine dihydrochloride; I-BET151 OPD tablets, Sigma Chemicals, USA) in phosphate-citrate buffer (0.4 mg/mL) containing 0.04% of 30% (v/v)

hydrogen peroxide, pH 5.0, were added to each well and the plates were incubated in the dark at room temperature for 15 min, and 50 μL of stop buffer (1-N H2SO4) then added.

Mean optical density (OD) at 492 nm was determined for all test wells using a microtiter plate reader (Multiskan MCC/340 MKII, Alabama, USA). For ELISA intra plate control we used two positive and two negative control sera. To accurately assess the assay for diagnostic specificity, sensitivity, cut-off and predictive values, the results from the 497 confirmed positive and negative samples were subjected to Receiver Operating Characteristic (ROC) analysis ADAMTS5 using MedCalc statistical software (version 10.3.0.0) (www.medcalc.be). The most appropriate cutoff was selected for the IFAT and ELISA using ROC analysis that plots the DSn (true positives/true positives + false negatives) and DSp (true negatives/true negatives + false positives) as a function of cutoff. To evaluate the test accuracy (the values of specificity and sensitivity) in the absence of a gold standard, the TAGS (Tests in the Absence of a Gold Standard) analysis were performed (Pouillot et al., 2002); for this we used two population, 2 tests (ELISA and IFAT), and no reference population. The antigenic domain of NcSRS2 located in the distal C-terminal two thirds of the molecule was clone and expressed in E. coli as inclusion bodies, then used as a recombinant antigen for ELISA-NcSRS2.

80, and on hard trials Phard = 0 60 Therefore, on average Pcombi

80, and on hard trials Phard = 0.60. Therefore, on average Pcombined = 0.70. With these probabilities of success we can generate the PE signals that would occur through the course of a trial and examine if these PEs match our neural data. At the beginning of a trial the predicted reward V(t0) is zero for each time t until the time of incentive presentation tpresentation. The initial presentation of incentive results in a positive prediction error δ = Pcombined∗V(tpresentation) − 0. At tpresentation participants are not

given any cues regarding trial difficulty, therefore their probability of success is Pcombined. These expectations result in positive prediction errors that increase with the magnitude of the incentive offered ( Figure 6B). It can be seen that this PE response mirrors the striatal activations Tanespimycin supplier we observed during incentive selleck presentation. When the motor task begins at tmotor, participants

update their prediction error depending on the difficulty of the trial: easy trials δ = Peasy∗V(tmotor) − Pcombined∗V(tpresentation); hard trials δ = Phard∗V(tmotor) − Pcombined∗V(tpresentation). This results in different PE responses for the different trial difficulties ( Figure 6C). Easy trials result in positive PEs that scale with the magnitude of the incentive, whereas hard trials result in negative PEs that also scale with the magnitude of incentive. Predicted PE responses for hard trials mimic our observed responses in striatum, however striatal responses for easy and combined trials do not align with the predictions

of the PE model. Instead, we see that observed responses for easy trials are exactly opposite those of the PE model (Figure S4). Furthermore, observed responses for the combined trials show deactivation, whereas the model predicts no PE response. Overall, the results of our simulation illustrate that a TD PE model is not sufficient to describe our observed neural responses to incentives. One might also consider a modified version of the PE model that incorporates a loss aversion parameter such that negative prediction errors loom larger than positive prediction errors. However, such Sclareol a revised PE model still does not capture the pattern of deactivations observed in the easy condition of our current task. To examine differences in brain activity as a function of unsuccessful versus successful performance, we contrasted unsuccessful and successful trials at the time of the motor task. We also examined an interaction between performance (i.e., unsuccessful and successful trials) and incentive level. We found no significant main effect of task performance. However, we did find a significant interaction between performance and incentive in the ventral striatum (Figure 7; Table S4), such that this region showed a greater deactivation as a function of incentive during unsuccessful trials compared to successful trials (cluster sizes > 100 voxels; right cluster peak: [x = 27; y = 0; Z = 0], T = 6.

Animals subjected to an inescapable stress environment typically

Animals subjected to an inescapable stress environment typically exhibit two different behaviors—active activity (swimming and climbing) and passive activity (immobility) (Lucki, 1997). Passive activity can thus be an indicator of behavioral despair in this paradigm (Porsolt et al., 1977). This passive activity can be reduced by acute or chronic treatment with clinical antidepressant drugs (Liu et al., 2010; Lu et al., 2006). We replicated this finding in rats treated with either a sub-anesthetic dose of ketamine (15 mg/kg i.p.) or fluoxetine (10 mg/kg i.p.). Fluoxetine and ketamine treated rats displayed

significantly reduced duration of passive activity in the forced swim test (Figure 6A) compared to saline-treated rats, confirming antidepressant-like Selleck Epigenetic inhibitor effects of these compounds in this behavioral paradigm. Additionally, diazepam did not have antidepressant-like effects in forced swim test (Figure 6B) even though it showed hyperexploration in OFT, suggesting specificity of this behavioral

test (Figure S6). To determine whether knockdown of HCN1 in the dorsal CA1 region can produce antidepressant-like effects, rats were microinjected bilaterally with lentivirus learn more expressing either shRNA-control or shRNA-HCN1. Similar to fluoxetine or ketamine treatment, knockdown of HCN1 was associated with an antidepressant-like effect compared with shRNA-control-infected animals (Figure 6C). Because shRNA-HCN1-infected rats displayed higher exploration activity

(Figures 5B and 5F) in the open field test, we further analyzed whether there was a relationship between exploration activity and duration of passive activity. We found, however, that there was no correlation between passive activity in FST and exploration activity in OFT (Figure 6D), suggesting specificity of antidepressant-like effects by knockdown of HCN1 in the dorsal hippocampal CA1 aminophylline region. Patients with treatment-resistant depression have pathologically altered activity in the limbic-cortical area (Mayberg et al., 2005). Animal models of depression induced by chronic mild stress display an increase in the ventral CA1 activity. This could be reversed by fluoxetine, highlighting the significance of hippocampal activity in the treatment of depression (Airan et al., 2007). Because genetic silencing of HCN1 gene in a small region of the dorsal hippocampal CA1 region produced anxiolytic- and antidepressant-like effects, it is possible that chronic knockdown of HCN1 could cause changes in hippocampal activity. We used voltage-sensitive dye (VSD) imaging to determine whether a localized, chronic knockdown of HCN1 can change hippocampal activity. We placed a stimulating electrode in the stratum radiatum (SR), near the border between the CA1 and CA2 regions to activate the Schaffer collaterals ( Chang et al., 2007). Both VSD optical signals and extracellular field potentials were recorded in the SR of the CA1 region ( Figures 7B and 7C).

We further explored the space of these two parameters (kfi   and

We further explored the space of these two parameters (kfi   and kfr  ) by measuring the impulse response at different contrasts for many different parameter values, thereby mapping the effects of kfi   and kfr   on changes in gain, temporal response, and the biphasic temporal response. Changes in gain resulted when either fast inactivation or recovery were slow compared to activation, thus leading to depletion of the resting state during increased activation ( Figure 8C). Considering a simplified three-state system at equilibrium, the inflow and outflow of all states are the same (i.e., R

 ∞u  ∞ka   = A  ∞ki   = I  ∞kr BMN 673 ic50  ), where u  ∞ is a steady input to the kinetics block. The equilibrium occupancy of the resting state can then be solved as equation(Equation 3) R∞=(1+u∞c1)−1,R∞=(1+u∞c1)−1,where c1=(ka/ki+ka/kr)c1=(ka/ki+ka/kr). Thus, when either ki or kr are small compared to ka, c1 becomes large and weights the effect of the input u∞ more heavily. This changes the resting state occupancy and, therefore, the gain (see Equation 2) significantly

with contrast. This relationship allows the adaptive change in gain to be approximated analytically directly from the rate constants Trametinib supplier of the model ( Figure S5A). Contrast-dependent changes in temporal filtering occurred when fast inactivation (kfi  ) was prolonged but such changes were unaffected by the rate constant of fast recovery (kfr  ) ( Figure 8D). Because of the lack of dependence on kfr  , we considered a simplified system of three states with no return pathway, R→ukaA→kfiI. We can derive that the impulse response of this system is a weighted sum of two exponentials (see Supplemental Experimental Procedures), one with a time constant, u∞(σ)kau∞(σ)ka, that depends on the contrast (σ  ), and one with time constant, kfi  , that is independent

very of contrast. The weighting between these two exponentials is set by a constant that depends on the contrast and the inactivation rate such that when kfi/kakfi/ka is small, the variable exponential is weighted more heavily. We can use this understanding to predict the adaptive change in temporal filtering directly from the rate constants of the model ( Figure S5B). Finally, the change in differentiation of the temporal filter was produced primarily by fast recovery, with some dependence on fast inactivation as well (Figure 8E). By comparing the state occupancies to the impulse response, Fk, we saw that Fk was more biphasic when the increase in the inactivated state I1 exceeded the depletion of the resting state ( Figure S5C). Consequently, when recovery was slow, as compared to the steps of activation and inactivation, there was transiently a higher level of inactivation, causing an undershoot in the level of activation.

Therefore, it is clear that these retinal neurons are endowed wit

Therefore, it is clear that these retinal neurons are endowed with polarity information that is not present in cultured neurons and allows them to extend axons directly PD-L1 mutation from the relevant part of the cell body. There are two potential

sources of information that neurons could exploit. Neurons derive from the terminal divisions of highly polarized neuroepithelial cells, and this inherited polarity could be instructing neuronal polarization. Alternatively (or additionally) neurons are born into highly heterogeneous environments, in which multiple potential extracellular cues exist that could provide polarizing information. Here we demonstrate that a major determinant

for the orientation of RGC polarization is in fact an extracellular cue acting upon the neuron. Just prior to axon extension, the RGC contacts the basal surface of the retina. Lining the basal surface of the retina is a basal lamina, which contains Lam1. For five reasons we conclude that Lam1 contact is the major cue instructing the RGCs to extend their axons at this precise point. First, contact with the retinal basal surface correlates with the specific and stable accumulation of the axonal marker Kif5c560-YFP. Antidiabetic Compound Library Second, in a retina devoid of Lam1 at its basal surface, RGCs show ectopic polarization behaviors and progress through a Stage 2 phase before extending an axon. Third, in a Lam1-deficient retina, centrosomes were localized appropriately and apically in very young RGCs, but mislocalized and wandering centrosomes are visible within Stage 2 RGCs. This suggests that Lam1 is Adenylyl cyclase most crucial to direct neuronal (rather than neuroepithelial) polarization, at least with respect to this marker in these specific cells. Fourth, when cultured RGCs contact a Lam1-coated bead, they will extend

their axons from the contact point. Fifth, and most importantly, when Lam1-coated beads are implanted into a Lam1 deficient retina, RGCs that contact the bead consistently extend their axon along the Lam1 surface. This is a clear demonstration that a molecularly defined cue is necessary and sufficient to orient the polarization of a vertebrate neuron in vivo. Importantly, the role of Laminin in neuronal polarization may not be limited to RGCs, because many neurons, including hindbrain and spinal cord neurons, extend axons along basal laminae. Also, the orientation of nucMLF neuron axon extension has been reported to be disrupted in zebrafish Lamα1 mutants, and knockout of lamγ1 in cortical neurons results in migratory and perhaps polarization defects, indicating that a Laminin-based cue may be important for directed polarization of diverse types of neurons ( Chen et al., 2009 and Wolman et al., 2008).

, 2001) Considering that C serrata n-hexane extract

inh

, 2001). Considering that C. serrata n-hexane extract

inhibited in vitro AChE of all tested brain areas from Wistar rats, we can suggest cholinergic side-effects of this extract and its consequently toxicity in mammals. Although in vivo studies of C. serrata n-hexane extract or their individual compounds are necessary in order to confirm the mammal toxicity, since processes of absorption may interfere on xenobiotic effects. On the other hand, inhibition of AChE is an important approach in the management for Alzheimer’s disease, senile dementia, ataxia, myasthenia gravis and Parkinson’s disease ( Brenner, 2000 and Rahman and Choudhary, 2001). Accordingly, the discovery of new molecules from plants can be a potential therapeutic CP-690550 ic50 strategy for the prevention and treatment of AD. To the best of our knowledge, we herein report the first findings on cholinesterase inhibitory activity of C. serrata. The n-hexane extract of C. serrata inhibited AChE activity on the larvae of R.

microplus and in brain structures of rats. We can suppose that this effect may be related to its ticks toxicity. Moreover, the chemistry LDK378 is not exhausted at this point and it is important to find out what or which substances are responsible for inhibitory AChE properties of n-hexane extract from C. serrata. Additionally, in vivo studies, using both ticks and mammals, must be performed. This work was supported by the Brazilian funding agencies: Conselho Nacional de Desenvolvimento Científico

e Tecnológico – CNPq (Dr. I.R. Siqueira, 2010; Dr. G.L.V. Poser, 2010; C. Vanzella, 2010; J.C. from Santos); Coordenação de Aperfeiçoamento de Pessoal de Nível Superior – CAPES (F. Moysés, 2010). “
“The cattle tick Rhipicephalus (Boophilus) microplus (Canestrini, 1887) (Acari: Ixodidae) is one of the most important parasites of cattle in tropical and subtropical countries. In Brazil, it is responsible for annual losses of about U$2 billion due to mortality, decrease in both milk production and weight gain, deteriorating effects on leather quality, costs for acaricide drugs and transmission of cattle fever disease agents ( Grisi et al., 2002). The control of R. microplus mainly relies on the use of chemical products mostly without following any technical criteria (leading to an excessive number of applications and too low volume of product per animal) which contributes to accelerating the development of resistance to acaricides ( Alonso-Díaz et al., 2006, Mendes et al., 2007 and Mendes et al., 2011). In Brazil, the first record of cattle tick resistance to organophosphates and pyrethroids was in the 1970s and 1980s, respectively ( Arteche, 1972 and Leite, 1991). Resistance persisted and now it is found throughout the country ( Alonso-Díaz et al., 2006, Andreotti et al., 2011 and Mendes et al., 2011).

Again, a prestimulus baseline measurement (the mean of 1 s of dat

Again, a prestimulus baseline measurement (the mean of 1 s of data before the stimulus) was subtracted from the Z score. We would like to thank Eric Behnke and Tony Fields for technical assistance and Nanthia Suthana for electrode localizations. This work was supported by a grant from the National Institutes of Health (NS033221) as well as a University of California President’s Postdoctoral Fellowship (awarded to B.A.L.). “
“(Neuron 75, 1114–1121; September 20, 2012) As the result of a journal GSK1349572 clinical trial error during the production process, an incorrect version of the Supplemental Information was previously published

with this article online. We have now corrected the online Supplemental Information and apologize for the error. “
“(Neuron 79, 1–14; July 24, 2013) On page 8, the text mistakenly reads, “The fact that marked plasticity of ensemble plasticity appeared in both depth levels of IL only during the critical overtraining period in which habits became crystallized suggested an unexpected role of IL in the formation Fasudil order of habits, not only in their expression.” This text should instead read, “The fact that marked plasticity of ensemble activity appeared in both depth levels of IL only during the critical overtraining period in which habits became crystallized suggested an unexpected

role of IL in the formation of habits, not only in their expression.” This error has been corrected in the printed and online versions of the paper. “
“Optogenetics has revolutionized neuroscience through the use of heterologously expressed light-sensitive opsins that are G protein-coupled receptors, ion channels, or pumps to stimulate or inhibit activity in genetically selected neurons and brain regions, opening exciting avenues to probe the role of those cells in circuit

function and behavior (Szobota and Isacoff, 2010, Miesenböck, 2011 and Yizhar et al., 2011). In addition to naturally light-sensitive opsins used in “classical” optogenetics, chemical synthesis combined with protein engineering has produced a complementary “chemical” optogenetics, or photopharmacology, out in which native mammalian channels, as well as ionotropic and metabotropic receptors, can be blocked, agonized, or antagonized by light, enabling presynaptic or postsynaptic neuronal responses to neurotransmitter release to be selectively controlled (Kramer et al., 2013 and Levitz et al., 2013). While the optical activation of presynaptic rhodopsin can partially inhibit transmitter release during illumination (Li et al., 2005) and a light-activated metabotropic glutamate receptor can do so and persist for many minutes in the dark (Levitz et al., 2013) and both can be rapidly turned off, a method for ablation of neurotransmitter release that lasts for many hours has been missing from the optogenetic quiver.

Importantly, in vitro results showed that this enhancement was po

Importantly, in vitro results showed that this enhancement was postsynaptic, calcium dependent, and required an activation of both NMDA and AMPA receptors matching the classical neocortical postsynaptic LTP. The cortical slow oscillation has a frequency of about 1 Hz (Steriade et al., 1993). One hertz stimulation usually induces long-term depression in neocortex, but irregular pattern of low-frequency stimulation does not (Perrett et al., 2001). During the silent phase, neurons are hyperpolarized and no firing occurs. During the active phase, neurons are depolarized and multiple presynaptic

spikes occur early after the onset of depolarization (Chauvette et al., 2010; Luczak et al., 2007). The network activities during sleep and the experimental protocol of the full sleep-like check details stimulation used

in this study are compatible with protocols of induction of spike-timing-dependent synaptic facilitation (Sjöström et al., 2008). The transition from hyperpolarized to depolarized states coupled with synaptic activities during active states is a natural pattern for spike-timing-dependent plasticity. Therefore, the presence of hyperpolarizing (silent) states appears to be a key component for the induction of LTP during sleep. According to the sleep synaptic homeostasis buy Alpelisib hypothesis (Tononi and Cirelli, 2003, 2006), SWS results in a general synaptic downscaling because of a strong reduction in gene expression contributing to LTP (Cirelli et al., 2004; Cirelli and Tononi, 2000a, 2000b). However, the total cortical level of kinase (CaMKII) does not change between sleep and waking state (Guzman-Marin et al., 2006; Vyazovskiy et al., 2008). Other Non-specific serine/threonine protein kinase studies have demonstrated that sleep-dependent memory consolidation requires the coactivation of both AMPA and NMDA receptors (Gais et al., 2008) and that sleep promotes LTP using a parallel involvement of protein kinase A, CaMKII, and ERK (Aton et al., 2009).

Sleep also promotes the translation of mRNAs related to plasticity (Seibt et al., 2012). Classical LTP consists in a calcium entry via NMDA receptors that will activate different kinase cascades, among which CaMKII would play a critical role by phosphorylating AMPA receptor. Once phosphorylated, GluR1-containing AMPA receptors are translocated to the synapse leading to LTP. Also, the translocation of AMPA receptors to the synapse (Lisman et al., 2012; Malinow and Malenka, 2002) that probably occurs during SWS does not require new gene expression. This indicates that synaptic potentiation leading to memory formation can occur during SWS despite a reduction in the expression of genes responsible for LTP. Are there inconsistencies of our results with previous studies? (1) After prolonged waking periods, the slope of callosal evoked responses increases (Vyazovskiy et al., 2008).

Figures 2D–2G show the marginal moments for each cochlear envelop

Figures 2D–2G show the marginal moments for each cochlear envelope of each sound in our ensemble. All four statistics vary considerably across natural sound textures. Their values for noise are also informative. The envelope means, which provide a coarse measure of the power spectrum, do not have exceptional values for noise, lying in the middle of the set of natural sounds. However, the remaining envelope moments for noise all lie near the lower bound of the values obtained for natural textures, indicating that natural sounds tend to be

sparser than noise (see also Experiment 2b) (Attias and Schreiner, 1998). Cjk=∑tw(t)(sj(t)−μj)(sk(t)−μk)σjσk,j,k∈[1…32]suchthat(k−j)∈[1,2,3,5,8,11,16,21]. Our model included the correlation of each cochlear subband envelope with a subset of eight of its neighbors, a number that was typically sufficient to reproduce the qualitative

find more form of the full correlation matrix (interactions between overlapping subsets of filters allow the correlations to propagate across subbands). This was also perceptually sufficient: we found informally that imposing fewer correlations sometimes produced perceptually Selleckchem CB-839 weaker synthetic examples, and that incorporating additional correlations did not noticeably improve the results. Figure 3B shows the cochlear correlations for recordings of fire, applause, and a stream. The broadband events present in fire and applause, visible as vertical streaks in the spectrograms of Figure 4B, produce correlations between the envelopes of different cochlear subbands. Cross-band correlation, or “comodulation,” is common in natural sounds (Nelken et al., 1999), and we found it to be to be a major source

of variation among sound textures. The stream, for instance, contains much weaker comodulation. The mathematical form of the correlation does not uniquely specify the neural instantiation. It could be computed directly, by averaging a product as in the above equation. Alternatively, it could be computed with squared sums and differences, Thymidine kinase as are common in functional models of neural computation (Adelson and Bergen, 1985): Cjk=∑tw(t)(sj(t)−μj+sk(t)−μk)2−(sj(t)−μj−sk(t)+μk)24σjσk. For the modulation bands, the variance (power) was the principal marginal moment of interest. Collectively, these variances indicate the frequencies present in an envelope. Analogous quantities appear to be represented by the modulation-tuned neurons common to the early auditory system (whose responses code the power in their modulation passband). To make the modulation power statistics independent of the cochlear statistics, we normalized each by the variance of the corresponding cochlear envelope; the measured statistics thus represent the proportion of total envelope power captured by each modulation band: Mk,n=∑tw(t)bk,n(t)2σk2,k∈[1…32],n∈[1…20].