m8ta
use https for features.
text: sort by
tags: modified
type: chronology
[0] Schicknick H, Schott BH, Budinger E, Smalla KH, Riedel A, Seidenbecher CI, Scheich H, Gundelfinger ED, Tischmeyer W, Dopaminergic modulation of auditory cortex-dependent memory consolidation through mTOR.Cereb Cortex 18:11, 2646-58 (2008 Nov)

[0] Froemke RC, Merzenich MM, Schreiner CE, A synaptic memory trace for cortical receptive field plasticity.Nature 450:7168, 425-9 (2007 Nov 15)

[0] Recanzone GH, Schreiner CE, Merzenich MM, Plasticity in the frequency representation of primary auditory cortex following discrimination training in adult owl monkeys.J Neurosci 13:1, 87-103 (1993 Jan)

{1451}
hide / / print
ref: -2018 tags: sparse representation auditory cortex excitatation inhibition balance date: 03-11-2019 20:47 gmt revision:1 [0] [head]

PMID-30307493 Sparse Representation in Awake Auditory Cortex: Cell-type Dependence, Synaptic Mechanisms, Developmental Emergence, and Modulation.

  • Sparse representation arises during development in an experience-dependent manner, accompanied by differential changes of excitatory input strength and a transition from unimodal to bimodal distribution of E/I ratios.

{1425}
hide / / print
ref: -0 tags: Kato fear conditioning GABA auditory cortex mice optogenetics SOM PV date: 02-04-2019 19:09 gmt revision:0 [head]

PMID-29375323 Fear learning regulates cortical sensory representation by suppressing habituation

  • Trained mice on CS+ and CS --> lick task.
    • CS+ = auditory tone followed by tailshock
    • CS- = auditory tone (both FM modulated, separated by 0.5 - 1.0 octave).
    • US = licking.
  • VGAT2-ChR2 or PV-ChR2
  • GABA-ergic silencing of auditory cortex through blue light illumination abolished behavior difference following CS+ and CS-.
  • Used intrinsic imaging to locate A1 cortex, then AAV - GCaMP6 imaging to lcoated pyramidal cells.
  • In contrast to reports of enhanced tone responses following simple fear conditioning (Quirk et al., 1997; Weinberger, 2004, 2015), discriminative learning under our conditions caused no change in the average fraction of pyramidal cells responsive to the CS+ tone.
    • Seemed to be an increase in suppression, and reduced cortical responses, which is consistent with habituation.
  • Whereas -- and this is by no means surprising -- cortical responses to CS+ were sustained at end of tone following fear conditioning.
  • ----
  • Then examined this effect relative to the two populations of interneurons, using PV-cre and SOM-cre mice.
    • In PV cells, fear conditioning resulted in a decreased fraction of cells responsive, and a decreased magnitude of responses.
    • In SOM cells, CS- responses were enhanced, while CS+ were less enhanced (the main text seems like an exaggeration c.f. figure 6E)
  • This is possibly the more interesting result of the paper, but even then the result is not super strong.

{981}
hide / / print
ref: Lim-2009.09 tags: auditory midbrain implant deaf cochlea stimulation inferior colliculus date: 01-03-2012 06:55 gmt revision:2 [1] [0] [head]

PMID-19762428[0] Auditory midbrain implant: a review.

  • Inferior to a cochlear implant -- subjects, at the best, could understand speech only with lip-reading cues.
  • But! It's safe, and offers some degree of perception.
  • Also see: PMID-21157353[1]
    • Neurofibramatosis type 2 can also lead to cochlear deafness.
    • Implanted in the dorsal and ventral cochlear nuclei in the lateral recess of the IVth ventricle of the brain stem.
    • EABRs (evoked auditory brain stem responses); even though these were associated with electrodes in the right place, they could not be used for device fitting (?)

____References____

[0] Lim HH, Lenarz M, Lenarz T, Auditory midbrain implant: a review.Trends Amplif 13:3, 149-80 (2009 Sep)
[1] O'Driscoll M, El-Deredy W, Ramsden RT, Brain stem responses evoked by stimulation of the mature cochlear nucleus with an auditory brain stem implant.Ear Hear 32:3, 286-99 (2011 May-Jun)

{656}
hide / / print
ref: Schicknick-2008.11 tags: dopamine plasticity auditory cortex date: 12-15-2008 04:13 gmt revision:1 [0] [head]

PMID-18321872[0] Dopaminergic Modulation of Auditory Cortex-Dependent Memory Consolidation through mTOR.

  • I will annotate this paper later, after winter break.

____References____

{614}
hide / / print
ref: Froemke-2007.11 tags: nucleus basalis basal forebrain acetylcholine auditory cortex potentiation voltage clamp date: 10-08-2008 22:44 gmt revision:2 [1] [0] [head]

PMID-18004384[0] A synaptic memory trace for cortical receptive field plasticity.

  • nucleus basalis = basal forebrain!
  • stimulation of the nucleus basalis caused a reorganization of the auditory cortex tuning curves hours after the few minutes of training.
  • used whole-cell current-clamp recording to reveal tone-evoked excitatory and inhibitory postsynaptyic currents.
  • pairing of nucleus basalis and auditory tone presentation (2-5 minutes) increased excitatory currents and decreased inhibitory currents as compared to other (control) frequencies.
  • tuning changes required simultaneous tone presentation and nucleus basalis stimulation. (Could they indiscriminately stimulate the NB? did they have to target a certain region of it? Seems like it.)
    • did not require postsynaptic spiking!
  • Pairing caused a dramatic (>7-fold) increase in the probability of firing bursts of 2+ spikes
  • Cortical application of atropine, an acetylcholine receptor antagonist, prevented the effects of nucleus basalis pairing.
  • the net effects of nucleus basalis pairing are suppression of inhibition (20 sec) followed by enhancement of excitation (60 sec)
  • also tested microstimulation of the thalamus and cortex; NB pairing increased EPSC response from intracortical microstim, but not from thalamic stimulation. Both cortical and thalamic stimulation elicited an effect in the voltage-clamped recorded neuron.
  • by recording from the same site (but different cells), they showed that while exitation persisted hours after pairing, inhibition gradually increased commensurate with the excitation.
  • Thus, NB stimulation leaves a tag of reduced inhibition (at the circuit level!), specifically for neurons that are active at the time of pairing.

____References____

{625}
hide / / print
ref: Recanzone-1993.01 tags: plasticity cortex learning auditory owl monkeys SUA date: 10-06-2008 22:46 gmt revision:1 [0] [head]

PMID-8423485[0] Plasticity in the frequency representation of primary auditory cortex following discrimination training in adult owl monkeys

  • Measured tonotopic organization (hence plasticity) in the owl monkey auditory cortex following training on a frequency discrimination task.
  • improvement in performance correlates with an improvement in neuronal tuning.
  • two controls:
    • monkeys that were engaged in a tactile discrimination task
    • monkeys that received the same auditory stimuli but had no reason to attend to it
  • lots of delicious behavior graphs

____References____