m8ta
use https for features.
text: sort by
tags: modified
type: chronology
[0] Atallah HE, Lopez-Paniagua D, Rudy JW, O'Reilly RC, Separate neural substrates for skill learning and performance in the ventral and dorsal striatum.Nat Neurosci 10:1, 126-31 (2007 Jan)

[0] Pawlak V, Kerr JN, Dopamine receptor activation is required for corticostriatal spike-timing-dependent plasticity.J Neurosci 28:10, 2435-46 (2008 Mar 5)

[0] Daw ND, Doya K, The computational neurobiology of learning and reward.Curr Opin Neurobiol 16:2, 199-204 (2006 Apr)

[0] Schultz W, Tremblay L, Hollerman JR, Reward processing in primate orbitofrontal cortex and basal ganglia.Cereb Cortex 10:3, 272-84 (2000 Mar)

[0] Graybiel AM, The basal ganglia: learning new tricks and loving it.Curr Opin Neurobiol 15:6, 638-44 (2005 Dec)

[0] Shidara M, Aigner TG, Richmond BJ, Neuronal signals in the monkey ventral striatum related to progress through a predictable series of trials.J Neurosci 18:7, 2613-25 (1998 Apr 1)

[0] Turner RS, DeLong MR, Corticostriatal activity in primary motor cortex of the macaque.J Neurosci 20:18, 7096-108 (2000 Sep 15)

[0] Afanas'ev SV, Tolkunov BF, Rogatskaya NB, Orlov AA, Filatova EV, Sequential rearrangements of the ensemble activity of putamen neurons in the monkey brain as a correlate of continuous behavior.Neurosci Behav Physiol 34:3, 251-8 (2004 Mar)

{208}
hide / / print
ref: -2012 tags: cortex striatum learning carmena costa basal ganglia date: 09-13-2019 18:30 gmt revision:6 [5] [4] [3] [2] [1] [0] [head]

PMID-22388818 Corticostriatal plasticity is necessary for learning intentional neuroprosthetic skills.

  • Trained a mouse to control an auditory cursor, as in Kipke's task {99}. Did not cite that paper, claimed it was 'novel'. oops.
  • Summed neuronal firing rate of groups of 2 or 4 M1 neurons.
  • Auditory feedback was essential for the operant learning.
    • One group increased the frequency with increased firing rate; the other decreased tone with increasing FR.
  • Specific deletion of striatal NMDA receptors impairs the ability to learn neuroprosthetic skills.
    • Hence, they argue, cortico-striatal plastciity is required to learn abstract skills, such as this tone to firing rate target acquisition task.
  • Controlled by recording EMG of the vibrissae + injection of lidocane into the whisker pad.
  • One reward was sucrose solution; the other was a food pellet. When the rat was satiated on one modality, they showed increased preference for the opposite reward during BMI control -- thereby demonstrating intentionality. Clever!.
  • Noticed pronounced oscillatory spike coupling, the coherence of which was increased in low-frequency bands in late learning relative to early learning (figure 3).
  • Genetic manipulations: knockin line that expresses Cre recombinase in both striatonigral and striatopallidal medium spiny neurons, crossed with mice carrying a floxed allele of the NMDAR1 gene.
    • These animals are relatively normal, and can learn to perform rapid sequential movements, but are unable to learn precise motor sequences.
    • Acute pharmacological blockade of NMDAR did not affect performance of the neuroprosthetic skill.
    • Hence the deficits in the transgenic mice are due to an inability to perform the skill.

{241}
hide / / print
ref: Costa-2006.1 tags: Rui Costa Miguel Nicolelis Dopamine depletion excess cortex striatum hyperkinesia akinesia parkinsons DAT-KO date: 03-02-2012 01:03 gmt revision:8 [7] [6] [5] [4] [3] [2] [head]

PMID-17046697 Rapid alterations in corticostriatal ensemble coordination during acute dopamine-dependent motor dysfunction.

  • used rats where they could rapidly switch between dopamine depletion (0.2%) and overexpression (500%)
  • most cortical and striatal neurons ( approximately 70%) changed firing rate during the transition between dopamine-related hyperkinesia and akinesia,
    • buuut the overall cortical firing rate remained unchanged
  • repeated dopamine depletion is accompanied by the loss of glutamergic synapses in striatopallidal neurons (Day et al 2006) PMID-16415865 (Kaneda et al 2005). PMID-16367790
  • with Marc Caron
  • Dopamine is believed to modulate positively the direct striatal pathway that contains predominantly D1-type receptors and disinhibits cortical neurons to modulate negatively the indirect pathway that predominantly contains D2-type receptors and increased crotical inhibition (Albin et al 1989 {1050}, Filion and Tremblay 1991; Gerfen 1992, Parr-Brownlie and Hyland, 2005).
  • According to the classical view (Albin et al 1989), lack of DA release should lead to inhibition of cortical activity and an inability to produce movement, while an excess of Dopamine should lead to increased cortical activity and hyperactivity (Gerfen, 1992).
    • mouse model: DDD PMID-17030735[] (dopamine transporter knockout)

{1144}
hide / / print
ref: -0 tags: dopamine reinforcement learning funneling reduction basal ganglia striatum DBS date: 02-28-2012 01:29 gmt revision:2 [1] [0] [head]

PMID-15242667 Anatomical funneling, sparse connectivity and redundancy reduction in the neural networks of the basal ganglia

  • Major attributes of the BG:
    • Numerical reduction in the number of neurons across layers of the 'feed forward' (wrong!) network,
    • lateral inhibitory connections within the layers
    • modulatory effects of dopamine and acetylcholine.
  • Stochastic decision making task in monkeys.
  • Dopamine and ACh deliver different messages. DA much more specific.
  • Output nuclei of BG show uncorrelated activity.
    • THey see this as a means of compression -- more likely it is a training signal.
  • Striatum:
    • each striatal projection neuron receives 5300 cortico-striatal synapses; the dendritic fields of same contains 4e5 axons.
    • Say that a typical striatal neuron is spherical (?).
    • Striatal dendritic tree is very dense, whereas pallidal dendritic tree is sparse, with 4 main and 13 tips.
    • A striatal axon provides 240 synapses in the pallidum and makes 10 contacts with one pallidal neuron on average.
  • I don't necessarily disagree with the information-compression hypothesis, but I don't disagree either.
    • Learning seems a more likely hypothesis; could be that we fail to see many effects due to the transient nature of the signals, but I cannot do a thorough literature search on this.

PMID-15233923 Coincident but distinct messages of midbrain dopamine and striatal tonically active neurons.

  • Same task as above.
  • both ACh (putatively, TANs in this study) and DA neurons respond to reward related events.
  • dopamine neurons' response reflects mismatch between expectation and outcome in the positive domain
  • TANs are invariant to reward predictability.
  • TANs are synchronized; most DA neurons are not.
  • Striatum displays the densest staining in the CNS for dopamine (Lavoie et al 1989) and ACh (Holt et al 1997)
    • Depression of striatal acetylcholine can be used to treat PD (Pisani et al 2003).
    • Might be a DA/ ACh balance problem (Barbeau 1962).
  • Deficit of either DA or ACh has been shown to disrupt reward-related learning processes. (Kitabatake et al 2003, Matsumoto 1999, Knowlton et al 1996).
  • Upon reward, dopaminergic neurons increase firing rate, whereas ACh neurons pause.
  • Primates show overshoot -- for a probabalistic relative reward, they saturate anything above 0.8 probability to 1. Rats and pigeons do not show this effect (figure 2 F).

{1136}
hide / / print
ref: -0 tags: DBS dopamine synaptic plasticity striatum date: 02-27-2012 21:57 gmt revision:7 [6] [5] [4] [3] [2] [1] [head]

PMID-11285003 Dopaminergic control of synaptic plasticity in the dorsal striatum.

  • Repetitive stimulation of corticostriatal fibers causes a massive release of glutamate and DA in the striatum, and depending on the glutamate receptor subtype preferentially activated, produces either long-term depression (LTD) or long-term potentiation (LTP) of excitatory synaptic transmission.
  • D1 and D2 (like) receptors interact synergistically to allow LTD formation, and in opposition while inducing LTP.
  • Stimulation of DA receptors has been shown to modulate voltage-dependent conductances in striatal spiny neurons, but it does not cause depolarization or hyperpolarization (Calabresi et al 2000a PMID-11052221; Nicola et al 2000)
  • Striatal spiny neurons present a high degree of colocalization of subtypes of DA and glutamate receptors. PMID-9215599
  • Striatal cells have up and down states. Wilson and Kawaguchi 1996 PMID-8601819
  • Both LTD and LTP are induced in the striatum by the repetitive stimulation of corticostriatal fibers.
    • Repetition is associated with the dramatic increase of both glutamate and DA in the striatum. (presynaptic?)
  • LTP is enhanced by blocking or removing D2 receptors.
  • More complexity here - in terms of receptors and blocking. (sure magnesium blocks NMDA receptors, but there are many other drugs used...)

{1140}
hide / / print
ref: -0 tags: dopamine reward prediction striatum error striatum orbitofrontal reward date: 02-24-2012 21:26 gmt revision:1 [0] [head]

PMID-11105648 Involvement of basal ganglia and orbitofrontal cortex in goal-directed behavior.

  • Many regions have a complex set of activations, but dopamine neurons appear more homogenous: they report the error in reward prediction.
    • "The homogeneity of responsiveness across the population of dopamine neurons indicates that this error signal is widely broadcast to dopamine terminal regions where it could provide a teaching signal for synaptic modifications underlying the learning of goal-directed appetitive behaviors."
    • Signals are not contingent on the type of behavior needed to obtain the reward, and hence represent a relatively 'pure' reward prediction error.
  • Unlike dopamine neurons, many striatal neurons respond to predicted rewards, although at least some may reflect the relative degree of predictability in the magnitude of the responses to reward.
  • Neuronal activations in the orbitofrontal cortex appear to involve less integration of behavioral and reward-related information, but rather incorporate another aspect of reward, the relative motivational significance of different rewards.
  • Processing is hierarchical (or supposed to be so):
    • Dopamine neurons provide a relatively pure signal of an error in reward prediction,
    • Striatal neurons signal not only reward, but also behavioral contingencies,
    • Orbitofrontal neurons signal reward and incorporate relative reward preference.

{1139}
hide / / print
ref: -0 tags: striatum microstimulation abnormal myclonus dyskinesia date: 02-24-2012 19:44 gmt revision:0 [head]

PMID-21508304 Discontinuous Long-Train Stimulation in the Anterior Striatum in Monkeys Induces Abnormal Behavioral States

  • Long-train microstimulation induces complex, abnormal behavior: finger licking and biting, dyskinesias, grooming; more anterior (associative) resulted in hyper, hypo manic or stereotyped behaviors.
  • Short-train stimulation induces myoclonic-like movements.

{965}
hide / / print
ref: Teagarden-2007.03 tags: STN striatum operant conditioning behavior rats 2006 DBS date: 02-15-2012 03:36 gmt revision:5 [4] [3] [2] [1] [0] [head]

PMID-17182916[0] Subthalamic and Striatal Neurons Concurrently Process Motor, Limbic, and Associative Information in Rats Performing an Operant Task

  • STN encodes behavioral events (reinforcement, nose poke, correct / incorrect trials). So does the striatum.
  • This study is rather nonspecific, but it makes sense that a conserved and well connected region is active during learning & general behavior.
    • That is, while the subthalamic nucleus is considered an output relay of the basal ganglia, more likely it operates in parallel to facilitate forms of learning; as such, responses are shown to rewards, cues, etc.

____References____

[0] Teagarden MA, Rebec GV, Subthalamic and striatal neurons concurrently process motor, limbic, and associative information in rats performing an operant task.J Neurophysiol 97:3, 2042-58 (2007 Mar)

{188}
hide / / print
ref: neuro notes-0 tags: STN globus_pallidus striatum diagram basal_ganglia date: 01-26-2012 17:16 gmt revision:1 [0] [head]

http://www.gpnotebook.co.uk/cache/-1248198589.htm (bitrotted)

  • note that the loop around both preserves sign, more or less, provided you take into account the D2 receptor along the 'indirect' pathway
  • this has some glaring flaws: the globus pallius external projects to the globus pallidus internal, cortex projects to STN, thalamus projects to striatum, etc.

http://www.portfolio.mvm.ed.ac.uk/studentwebs/session1/group71/john.htm

  • has a good diagram of the neurotransmitters involved in the motor selection pathway. need to understand the kinetics of the dopamine receptor family

{612}
hide / / print
ref: Atallah-2007.01 tags: striatum skill motor learning VTA substantia nigra basal ganglia reinforcement learning date: 12-31-2011 18:59 gmt revision:3 [2] [1] [0] [head]

PMID-17187065[0] Separate neural substrates for skill learning and performance in the ventral and dorsal striatum.

  • good paper. via SCLin's blog. slightly confusing anatomical terminology.
  • tested in rats, which has a anatomically different basal ganglia system than primates.
  • Rats had to choose which driection in a Y maze based on olfactory cues. Normal rats figure it out in 60 trials.
  • ventral striatum (nucleus accumbens here in rats) connects to the ventral prefrontal cortices (for example, the orbitofrontal cortex)
    • in primates, includes the medial caudate, which has been shown in fMRI to respond to reward prediction error. Neural activity in the caudate is attenuated when a monkey reaches optimal performance.
  • dorsal parts of the striatum (according to web: caudate, putamen, globus pallidus in primates) connect to the dorsal prefrontal and motor cortices
    • (according to them:) this corresponds to the putamen in primates. Activity in the putamen reflects performance but not learning.
    • activity in the putamen is highest after successful learning & accurate performance.
  • used muscimol (GABAa agonist, silences neural activity) and AP-5 (blocks NMDA based plasticity), in each of the target areas.
  • dorsal striatum is involved in performance but not learning
    • Injection of muscimol during acquisition did not impair test performance
    • Injection of muscimol during test phase did impair performance
    • Injection of AP-5 during acquisition had no effect.
    • in acquisition sessions, muscimol blocked instrumental response (performance); but muscimol only has a small effect when it was injected after rats perfected the task.
      • Idea: consistent behavior creates a stimulus-response association in extrastriatal brain areas, e.g. cerebral cortex. That is, the basal ganglia is the reinforcement signal, the cortex learns the association due to feedback-driven behavior? Not part of the habit system, but make and important contribution to goal-directed behavior.
      • This is consistent with the observation that behavior is initially goal driven but is later habitual.
    • Actually, other studies show that plasticity in the dorsal striatum may be detrimental to instrumental learning.
    • The number of neurons that fire just before the execution of a response is larger in the putamen than the caudate.
  • ventral striatum is involved in learning and performance.
    • Injection of AP-5 or muscimol during acquisition (learning behavior) impairs test performance.
    • Injection of AP-5 during test performance has no effect , but muscimol impairs performance.
  • Their data support an actor-director-critic architecture of the striatum:
    • Actor = dorsal striatum; involved in performance, but not in learning them.
    • Director = ventral striatum; quote "it somehow learns the relevant task demands and directs the dorsal striatum to perform the appropriate action plans, but, crucially, it does not train the dorsal striatum"
      • ventrai striatum acts through the orbitofrontal cortex that mantains representations of task-reward contingencies.
      • ventral striatum might also select action selection through it's projections to the substantia nigra.
    • Critic = dopaminergic inputs from the ventral tegmental area and substantia nigra.

____References____

{115}
hide / / print
ref: Kemp-1971.09 tags: globus pallidus striatum 1971 neuroanatomy date: 12-07-2011 04:03 gmt revision:1 [0] [head]

PMID-4399123[0] The connexions of the striatum and globus pallidus: synthesis and speculation. !! great figures, great synthesis !!

  • a striking feature of the striatum (caudate and putamen, functionally the same is the dense axonal plexus - this receives a major contribution from the contralateral branches the short axon terminals (interneurons) as well as afferent projections. perhaps the most important characteristic of the axonal plexus is that all the component fibers cross dendrites rather than lie parallel to them -- just like the cerebellum''.
  • the cerebellum also has excitatory input and inhibitory output. similar structure to do a similar thing? ++ plenty of interneurons ++plenty of dendritic spines.
  • all of the cerebral cortex projects to the cerebellum, even the visual cortex has projections to the pontine nuclei. however, there is an exceptionallly small projection from the visual cortex to both the cerebellum and striatum.

____References____

[0] Kemp JM, Powell TP, The connexions of the striatum and globus pallidus: synthesis and speculation.Philos Trans R Soc Lond B Biol Sci 262:845, 441-57 (1971 Sep 30)

{689}
hide / / print
ref: HilArio-2007.01 tags: Rui Costa endocannabinoid habit reward striatum basal ganglia date: 03-05-2009 19:04 gmt revision:0 [head]

PMID-18958234 Endocannabinoid Signaling is Critical for Habit Formation.

  • quick review (the intro is packed with grat information):
    • in goal-directed learning, behavior is highly sensitive to the incentive value of the outcome, and contingency between the action and the outcome.
    • with repetition actions become both more efficient and more automatic.
    • after extensive training, rats move from goal-directed behavior to more habitual response independent of outcome value.
      • random interval schedules favor this more than random ratio reward schedules.
        • in mice, random interval schedules promoted habit formation, whereas random ratio schedules promoted acquisition of goal-directed behaviors. does this also apply to humans? I would guess so. Might be an interesting tool to have in the toolbox.
        • interval schedules promoted the exploration of a random lever whereas ratio schedules promoted the exploitation of the reward lever.
    • the underlying circuitry supporting goal-directed behav and habit formation are different:
      • goal directed behavior seems to require the associative BG/cortex including:
        • dorsomedial or associative striatum (medial!)
          • COMT, a transporter, is more highly expressed here than DAT.
        • pre-limbic ctx
        • mediodorsal thalamus
      • habit formation requries:
        • dorsolateral or sensorimotor striatum (lateral!)
          • DAT, dopamine transporter, is highly expressed here.
        • infralimbic cortex
    • amphetamine sensitization can lead to increased spine density in medium spiny neurons in the dorsolateral striatum, while decreasing spine density in the dorsomedial striatum. (interesting!)
    • lesions of nigrostriatal input to dorsolateral striatum impairs habit formation;
    • infusion of dopamine into the ventral medial prefrontal cortex favors goal-directed behavior
      • that is a rather broad statement to make ...
  • endocannabinoid release in the striatum is required for LTD induction.
  • endocannabinoid signaling regulated bt DA.
  • CB1 (the receptor implicated in addiction) is highly expressed in the dorsolateral striatum (habit!) at both excitatory and inhibitory terminals.
  • used mice with CB1 mutations therefore!
  • CB1 mutant mice have impaired habit formation and enhanced exploration.
    • suggest that endocannabinoid signaling is critical for both habit formation and increased exploration in interval schedules.

{633}
hide / / print
ref: Pawlak-2008.03 tags: dopamine striatum cortex STDP plasticity NMDAR date: 10-08-2008 17:24 gmt revision:1 [0] [head]

PMID-18322089[0] Dopamine Receptor Activation Is Required for Corticostriatal Spike-Timing-Dependent Plasticity

  • Single action potentials (APs) backpropagate into the higher-order dendrites of striatal spiny projection neurons during cortically driven "up" states (Kerr and Plenz, 2004)
    • note: many 'up' states in the striatum do not contain an AP.
  • Blocking dopamine D1/D5 receptors prevented both LTD and LTP induction.
  • first paragraph has a ton of references! They note that burst spiking in cortical and striatal projection neurons is infrequent - mostly, there are single spikes - and so STDP investigations are more applicable than high frequency stimulation LTP induction.
  • tested in vitro -- para-horizontal sections into the dorsolateral striatum of young rat brain, whole-cell current clamp, GABA_A currents blocked.
  • striatal projection neurons (SPNs) have a strange mode of AP generation - their membrane potential rises for 120ms after current injection, followed by a spike. They used this and infrared differential microscopy of morphology to locate the projection neurons.
  • stimulated using extracellular current to layer 5 of the cortex or nearby white matter. kept microstim current to a minimum.
  • paired this with AP generation in the SPNs at varying time delays, both at low frequency (0.1Hz)
  • there are a few cholinergic neurons in the striatum, apparently.
  • demonstrated STDP: "synaptic strength is maximally enhanced when cortically evoked EPSPs lead a spike by 10 ms, whereas synaptic strength is maximally depressed when EPSPs follow a spike by 30 ms"
  • also tried eliciting bursts in the SPN, but: "the timing of EPSPs with single APs is as efficient in inducing synaptic plasticity as the timing of EPSPs with AP bursts"
  • the STDP / LTP / LTD was NMDA-R dependent.
  • blocked D1/D5 with SCH-23390, and found that they could not induce LTP / LTD.
  • block of D2 receptor advanced the onset of LTP and delayed the onset of LTD, to a less dramatic degree than the D1/D5 block. Long-term LTP/LTD magnitude was not effected.
  • why did these guys get in J. Neuroscience where as this is in Science? because the Science article studied medium spiny neurons, with GFP labeling the D1/D2 receptors?

____References____

{631}
hide / / print
ref: Daw-2006.04 tags: reinforcement learning reward dopamine striatum date: 10-07-2008 22:36 gmt revision:1 [0] [head]

PMID-16563737[0] The computational neurobiology of learning and reward

  • I'm sure I read this, but cannot find it in m8ta anymore.
  • short, concise review article.
  • review evidence for actor-critic architectures in the prefrontal cortex.
  • cool: "Perhaps most impressively, a trial-by-trial regression analysis of dopamine responses in a task with varying reward magnitudes showed that the response dependence on the magnitude history has the same form as that expected from TD learning". trial by trial is where it's at! article: Midbrain Dopamine Neurons Encode a Quantitative Reward Prediction Error Signal

____References____

{628}
hide / / print
ref: Schultz-2000.03 tags: review orbitofrontal cortex basal ganglia dopamine reward reinforcement learning striatum date: 10-07-2008 03:53 gmt revision:1 [0] [head]

PMID-10731222[0] Reward processing in primate orbitofrontal cortex and basal ganglia

  • Orbitofrontal neurons showed three principal forms of reward-related activity during the performance of delayed response tasks,
    • responses to reward-predicting instructions,
    • activations during the expectation period immediately preceding reward and
    • responses following reward
    • above, reward-predicting stimulus in a dopamine neuron. Left: the animal received a small quantity of apple juice at irregular intervals without performing in any behavioral task. Right: the animal performed in an operant lever-pressing task in which it released a touch-sensitive resting key and touched a small lever in reaction to an auditory trigger signal. The dopamine neuron lost its response to the primary reward and responded to the reward-predicting sound.
  • for the other figures, read the excellent paper!

____References____

{67}
hide / / print
ref: Graybiel-2005.12 tags: graybiel motor_learning reinforcement_learning basal ganglia striatum thalamus cortex date: 10-03-2008 17:04 gmt revision:3 [2] [1] [0] [head]

PMID-16271465[] The basal ganglia: Learning new tricks and loving it

  • learning-related changes occur significantly earlier in the striatum than the cortex in a cue-reversal task. she says that this is because the basal ganglia instruct the cortex. I rather think that they select output dimensions from that variance-generator, the cortex.
  • dopamine agonist treatment improves learning with positive reinforcers but not learning with negative reinforcers.
  • there is a strong hyperkinetic pathway that projects directly to the subthalamic nucleus from the motor cortex. this controls output of the inhibitor pathway (GPi)
  • GABA input from the GPi to the thalamus can induce rebound spikes with precise timing. (the outputs are therefore not only inhibitory).
  • striatal neurons have up and down states. recommended action: simultaneous on-line recording of dopamine release and spike activity.
  • interesting generalization: cerebellum = supervised learning, striatum = reinforcement learning. yet yet! the cerebellum has a strong disynaptic projection to the putamen. of course, there is a continuous gradient between fully-supervised and fully-reinforcement models. the question is how to formulate both in a stable loop.
  • striosomal = striatum to the SNc
  • http://en.wikipedia.org/wiki/Substantia_nigra SNc is not an disorganized mass: the dopamergic neurons from the pars compacta project to the cortex in a topological map, dopaminergic neurons of the fringes (the lowest) go to the sensorimotor striatum and the highest to the associative striatum

____References____

{257}
hide / / print
ref: Shidara-1998.04 tags: ventral striatum nucleus accumbens monkey reward progress cue date: 03-27-2007 14:39 gmt revision:0 [head]

PMID-9502820[] Neuronal signals in the monkey ventral striatum related to progress through a predictable series of trials

  • neurons seem to cue/indicate/keep track of the state that a monkey is in during a sequence of reward-motivated behavior, e.g. there are neurons here which respond to the first trial, another group to anything other than 1st, others to first trial of schedules longer than one.
    • the recording site.

____References____

{238}
hide / / print
ref: SidibAc)-1997.06 tags: GPi anatomy retrograde tracing VL ventrolateral CM centromedian thalamus GPe striatum date: 03-11-2007 06:08 gmt revision:0 [head]

PMID-9183697 Efferent connections of the internal globus pallidus in the squirrel monkey: I. Topography and synaptic organization of the pallidothalamic projection.

  • ventrolateral (e.g. toward the bottom & side :) GPi projects to the postcommisural putamen & the VL thalamus & central CM.
  • dorsal GPi projects to the caudate and ventral striatum ("limbic striatum")
  • both areas also project to nuclei in the thalamus:
    • parvocellular ventral anterior nucleus (VApc)
    • dorsal VL
    • caudal CM/PF
  • the parafasicular nucleus (PF) was a site of a large number of associative/limbic projections.

{235}
hide / / print
ref: Turner-2000.09 tags: M1 striatum corticostriatal projections caudate putamen date: 03-11-2007 05:27 gmt revision:3 [2] [1] [0] [head]

PMID-10995857[0] Corticostriatal activity in primary motor cortex of the macaque.

  • corticostriatal neurons have markedly different properties than neurons that project to cerebral peduncle:
    • basal firing rate is very low
    • slow conduction velocities
    • premovement activity is small and highly directionally tuned
  • in comparison, cortical neurons which project to the peduncle show (mostly) muscle-related activity.
  • most likely the cerebrum transmits information in a very sparse way to the striatum.

____References____

{197}
hide / / print
ref: Afanasev-2004.03 tags: striatum learning reinforcement electrophysiology putamen russians date: 02-05-2007 17:33 gmt revision:3 [2] [1] [0] [head]

PMID-15151178[0] Sequential Rearrangements of the Ensemble Activity of Putamen Neurons in the Monkey Brain as a Correlate of Continuous Behavior

  • recorded 6-7 neurons in the putamen during alternative spatial selection
  • used discriminant analysis (whats that?) to analyze re-arrangements in spike activity
  • dynamics of re-arrangnement were dependent on reinforcement, and mostly contralateral striatum

____References____

{191}
hide / / print
ref: Kerr-2004.01 tags: UP_DOWN states striatum cortex spike timing date: 0-0-2007 0:0 revision:0 [head]

PMID-14749432 Action Potential Timing Determines Dendritic Calcium during Striatal Up-States

  • striatum has up/down states too!
  • only read the abstract.

{193}
hide / / print
ref: Di-1994.06 tags: dopamine NMDA striatum globus_pallidus ion_channels neurotransmitters date: 0-0-2007 0:0 revision:0 [head]

PMID-7521083 Modulatory functions of neurotransmitters in the striatum: ACh/dopamine/NMDA interactions.

  • in striatum, 2 basic classes of neural transmission:
    • fast neural transmission:
      • glutamate response in striatum to cortical/thalamic input via AMPA on medium spiny neurons
      • GABA output of the striatum
    • modulatory neural transmission:
      • NMDA
      • DA dopamine
      • substance P
      • ACh acetylecholine (large aspiny neurons, 30um soma! 1-2% of the population)
  • input to the cholinergic large aspiny neurons
    • GABA/substance P medium-spiny neurons which project to SNr + GPi
    • DA neurons from tegmentum, a8 a9 a10 groups
    • Glu neurons in the thalamus, and, to a lesser extent, from the cortex
  • DA D2 autoreceptors inhibit/regulate the release of DA, and it can also modulate the release of ACh + glu
    • specifically D2 has been demonstrated to inhibit ACh release, but not D1 (accourse)
  • figure 2 is kinda nice for the neurotransmitters in the basal ganglia
  • not really all that clear of an article