Heavily T2-weighted high-field MR images provide a unique opportunity for the evaluation of the extrapyramidal motor system. The images are affected by the presence of small amounts of naturally occurring paramagnetic substances-principally ironthat delineate the neostriatum (caudate and putamen), globus pallidus, red nucleus, substantia nigra, and dentate nucleus, primarily by a decrease in si...

BACKGROUND AND PURPOSE The neostriatum is known to be affected in HD. In this work, our aim was to determine whether microstructural and volumetric alterations occur in the neostriatum of presymptomatic HD gene carriers and in patients with early-stage HD. MATERIALS AND METHODS We studied a group of 15 presymptomatic gene carriers who were far from the estimated symptom onset (16% probability...

The purpose of the present study was to examine whether cAMP-dependent mechanisms regulated excitatory synaptic transmission in the neostriatum. A brain slice preparation was utilized for intracellular recordings of the excitatory postsynaptic potentials (EPSPs) evoked by electrical stimulation. Bath application of forskolin, an activator of adenylate cyclase, enhanced the EPSP amplitude and du...

The axonal arbors of single nigrostriatal dopaminergic neurons were visualized with a viral vector expressing membrane-targeted green fluorescent protein in rat brain. All eight reconstructed tyrosine hydroxylase-positive dopaminergic neurons possessed widely spread and highly dense axonal arborizations in the neostriatum. All of them emitted very little axon collateral arborization outside of ...

Heavily T2-weighted high-field MR images provide a unique opportunity for the evaluation of the extrapyramidal motor system. The images are affected by the presence of small amounts of naturally occurring paramagnetic substances--principally iron--that delineate the neostriatum (caudate and putamen), globus pallidus, red nucleus, substantia nigra, and dentate nucleus, primarily by a decrease in...

The neostriatum and its connections control the sequential organization of action ("action syntax") as well as simpler aspects of movement. This study focused on sequential organization of rodent grooming. Grooming syntax provides an opportunity to study how neural systems coordinate natural patterns of serial order. The most stereotyped of these grooming patterns, a "syntactic chain," has a pa...

How does the brain create rule-governed sequences of behavior? An answer to this question may come from a surprising source: the neostriatum (caudate nucleus and plltamen). Traditionally, the neostriatum has been considered part ofthe brain's motor system, but its colltribution to the preparation or execution of movement is recognized generally to concern high-level motor functions. Recent work...

Developmental regulation of the potassium conductance is important for the maturation of neuronal excitability and the formation of functional circuitry in the central nervous system (CNS). The rapidly inactivating A-type current is a major component of the voltage-dependent outward potassium currents in the large aspiny (LA) neurons in the neostriatum. The large aspiny neurons play important r...

We characterized the organization of corticostriatal projections from rodent primary somatosensory cortex (SI), testing the hypothesis that projections from SI areas representing subcomponents of the forelimb exhibit greater neostriatal overlap than projections from areas representing separate body parts. The anterograde tracers Fluoro-Ruby (FR), Alexa Fluor (AF), and biotinylated dextran amine...

Dopamine and glutamate are key neurotransmitters involved in learning and memory mechanisms of the brain. These two neurotransmitter systems converge on nerve cells in the neostriatum. Dopamine modulation of activity-dependent plasticity at glutamatergic corticostriatal synapses has been proposed as a cellular mechanism for learning in the neostriatum. The present research investigated the role...