Associative reinstatement memory measures hippocampal function in Parkinson's Disease.

In Parkinson's Disease (PD), hippocampal atrophy is associated with rapid cognitive decline. Hippocampal function is typically assessed using memory tests but current clinical tools (e.g.

Regional anatomy of the pedunculopontine nucleus: relevance for deep brain stimulation.

The pedunculopontine nucleus (PPN) is currently being investigated as a potential deep brain stimulation target to improve gait and posture in Parkinson's disease. This review examines the complex anatomy of the PPN region and suggests a functional mapping of the surrounding nuclei and fiber tracts that may serve as a guide to a more accurate placement of electrodes while avoiding potentially adverse effects. The relationships of the PPN were examined in different human brain atlases.

Decreased cerebral cortical serotonin transporter binding in ecstasy users: a positron emission tomography/[(11)C]DASB and structural brain imaging study.

Animal data indicate that the recreational drug ecstasy (3,4-methylenedioxymethamphetamine) can damage brain serotonin neurons. However, human neuroimaging measurements of serotonin transporter binding, a serotonin neuron marker, remain contradictory, especially regarding brain areas affected; and the possibility that structural brain differences might account for serotonin transporter binding changes has not been explored. We measured brain serotonin transporter binding using [(11)C] N,N-dimethyl-2-(2-amino-4-cyanophenylthio) benzylamine in 50 control subjects and in 49 chronic (mean 4 years) ecstasy users (typically one to two tablets bi-monthly) withdrawn from the drug (mean 45 days).

Increased vesicular monoamine transporter binding during early abstinence in human methamphetamine users: Is VMAT2 a stable dopamine neuron biomarker?

Animal data indicate that methamphetamine can damage striatal dopamine terminals. Efforts to document dopamine neuron damage in living brain of methamphetamine users have focused on the binding of [(11)C]dihydrotetrabenazine (DTBZ), a vesicular monoamine transporter (VMAT2) positron emission tomography (PET) radioligand, as a stable dopamine neuron biomarker. Previous PET data report a slight decrease in striatal [(11)C]DTBZ binding in human methamphetamine users after prolonged (mean, 3 years) abstinence, suggesting that the reduction would likely be substantial in early abstinence.

Comparison of three methods of targeting the subthalamic nucleus for chronic stimulation in Parkinson's disease.

Objective: The success of subthalamic nucleus (STN) surgery for Parkinson's disease depends on accuracy in target determination. The objective of this study was to determine which of the following techniques was most accurate and precise in identifying the location for stimulation in STN deep brain stimulation surgery that is most clinically effective: direct targeting, indirect targeting using the positions of the anterior and posterior commissures, or a technique using the red nucleus (RN) as an internal fiducial marker.

Methods: We reviewed 14 patients with Parkinson's disease treated with bilateral STN deep brain stimulation (28 STN targets).

Elevated serotonin transporter binding in depressed patients with Parkinson's disease: a preliminary PET study with [11C]DASB.

This study investigated whether abnormalities in serotonin transporter binding occur in Parkinson's disease (PD) patients with concurrent depression. We estimated serotonin transporter levels in seven clinically depressed early-stage PD patients and in seven healthy matched-control subjects during a single positron emission tomography (PET) scan with the serotonin transporter radioligand, [(11)C]DASB. Depressed PD patients displayed a wide-spread increase (8-68%) in [(11)C]DASB specific binding outside of the striatum, which was significant in dorsolateral (37%) and prefrontal (68%) cortices.

Involvement of the basal ganglia and cerebellar motor pathways in the preparation of self-initiated and externally triggered movements in humans.

The subthalamic nucleus (STN) is part of the cortico-basal ganglia (BG)-thalamocortical circuit, whereas the ventral lateral nucleus of the thalamus (VL) is a relay nucleus in the cerebello-dentato-thalamocortical (CTC) pathway. Both pathways have been implicated in movement preparation. We compared the involvement of the STN and VL in movement preparation in humans by recording local field potentials (LFPs) from seven patients with Parkinson's disease with deep-brain stimulation (DBS) electrodes in the STN and five patients with tremor and electrodes in VL.

Levodopa response in long-term bilateral subthalamic stimulation for Parkinson's disease.

Subthalamic nucleus deep brain stimulation (STN-DBS) is effective in advanced Parkinson's disease (PD), but its effects on the levodopa response are unclear. We studied the levodopa response after long-term STN-DBS, STN-DBS efficacy and predictive value of preoperative levodopa response to long-term DBS benefit in 33 PD patients with bilateral STN-DBS. Patients were assessed using the Unified Parkinson's Disease Rating Scale preoperatively (with and without medications) and postoperatively (without medications or stimulation, with only medications or stimulation, and with both medications and stimulation).

Subthalamic nucleus stimulation: improvements in outcome with reprogramming.

Background: Deep brain stimulation (DBS) is currently the most effective surgical treatment for advanced Parkinson disease (PD). Even when the electrode is well positioned in the target, the optimization of clinical results depends on careful programming of electrical parameters and changes in antiparkinsonian drug dosages.

Objective: To determine whether stable outcomes from subthalamic nucleus DBS for PD can be improved by revising stimulation parameters and drug dosages through "hands-on" involvement of a neurologist expert in both movement disorders and DBS programming.

Speech and nonspeech sequence skill learning in adults who stutter.

Unlabelled: Two studies compared the speech and nonspeech sequence skill learning of nine persons who stutter (PWS) and nine matched fluent speakers (PNS). Sequence skill learning was defined as a continuing process of stable improvement in speed and/or accuracy of sequencing performance over practice and was measured by comparing PWS's and PNS's performance curves of accuracy, reaction time, and sequence duration, as well as retention and transfer. In experiment one, participants completed a 30-trial finger tapping sequence and in experiment two, a 30-trial read-aloud sequence of nonsense syllables.

Exploring the recognition memory deficit in Parkinson's disease: estimates of recollection versus familiarity.

Current theories postulate that recognition memory can be supported by two independent processes: recollection (i.e. vivid memory for an item and the contextual details surrounding it) versus familiarity (i.

Psychiatric symptoms following surgery for Parkinson's disease with an emphasis on subthalamic stimulation.

Bilateral subthalamic stimulation is a very effective neurosurgical treatment for advanced Parkinson's disease. Despite the range and frequency of psychiatric symptoms occurring in the postoperative state, most of these symptoms are transient and manageable. In clinical practice, preoperative psychiatric vulnerability, as with that of preoperative cognitive status, takes on an important role.

Psychiatric symptoms in patients with Parkinson disease presenting for deep brain stimulation surgery.

Object: Postoperative psychiatric symptoms have been associated with subthalamic deep brain stimulation (DBS) for Parkinson disease (PD), and preoperative psychiatric vulnerability, the effects of surgery, stimulation, medication changes, and psychosocial adjustment have been proposed as causative factors. The variables involved in whether preoperative psychiatric symptoms improve or worsen following surgery are not yet known. In the present study, preoperative psychiatric symptoms were systematically assessed in patients with PD presenting for routine preoperative psychiatric assessment.

Comparison of 2-dimensional magnetic resonance imaging and 3-planar reconstruction methods for targeting the subthalamic nucleus in Parkinson disease.

Objective: The study aims to compare 2-dimensional (2D) and 3-planar (3P) reconstruction magnetic resonance imaging (MRI) methods of targeting the optimal region of the subthalamic nucleus (STN) for chronic stimulation in patients with Parkinson disease.

Methods: We studied 14 patients with Parkinson disease treated with bilateral STN deep brain stimulation (DBS) (28 STN targets). Electrode implantation was based on direct and indirect targeting based upon the position of the anterior and posterior commissures using 2D MRI, with selection of the final target based on microelectrode recording.

Comparison of three methods of targeting the subthalamic nucleus for chronic stimulation in Parkinson's disease.

Objective: The success of subthalamic nucleus (STN) surgery for Parkinson's disease depends on accuracy in target determination. The objective of this study was to determine which of the following techniques was most accurate and precise in identifying the location for stimulation in STN deep brain stimulation surgery that is most clinically effective: direct targeting, indirect targeting using the positions of the anterior and posterior commissures, or a technique using the red nucleus (RN) as an internal fiducial marker.

Methods: We reviewed 14 patients with Parkinson's disease treated with bilateral STN deep brain stimulation (28 STN targets).

Correspondence of microelectrode mapping with magnetic resonance imaging for subthalamic nucleus procedures.

Background: Magnetic resonance imaging (MRI) and microelectrode recording (MER) are commonly used to guide stereotactic procedures on the subthalamic nucleus (STN). Little is known about the correlation between the position of the STN as seen on MRI and that as determined by MER mapping. We compared these in 10 patients with Parkinson's disease.

Subthalamic nucleus deep brain stimulation for parkinson's disease after successful pallidotomy: clinical and electrophysiological observations.

Unilateral pallidotomy is an effective treatment for contralateral parkinsonism and dyskinesia, yet symptoms progress in many patients. Little is known about whether such patients obtain a useful response to subsequent bilateral subthalamic nucleus deep brain stimulation (STN DBS). Changes in Unified Parkinson's Disease Rating Scale (UPDRS) Motor and Activities of Daily Living (ADL) scores, medication requirements, and dyskinesias were measured.

Involvement of human thalamus in the preparation of self-paced movement.

Cortical areas participating in the preparation of voluntary movements have been studied extensively. There is emerging evidence that subcortical structures, particularly the basal ganglia, also contribute to movement preparation. The thalamus is connected to both the basal ganglia and the cerebellar pathways, but its role in movement preparation has not been studied extensively in humans.

Bilateral globus pallidus internus deep brain stimulation in tardive dyskinesia: a case report.

The clinical response of a 53-year-old woman with tardive dyskinesia treated with bilateral globus pallidus interna deep brain stimulation is described. At 18 months follow-up, her Burke-Fahn-Marsden Dystonia Rating Scale score fell from 52 (preoperative) to 21 (60% improvement).

Determining the position and size of the subthalamic nucleus based on magnetic resonance imaging results in patients with advanced Parkinson disease.

Object: The subthalamic nucleus (STN) is a target in surgery for Parkinson disease, but its location according to brain atlases compared with its position on an individual patient's magnetic resonance (MR) images is incompletely understood. In this study both the size and location of the STN based on MR images were compared with those on the Talairach and Tournoux, and Schaltenbrand and Wahren atlases.

Methods: The position of the STN relative to the midcommissural point was evaluated on 18 T2-weighted MR images (2-mm slices).

Primary dystonia is more responsive than secondary dystonia to pallidal interventions: outcome after pallidotomy or pallidal deep brain stimulation.

Objective: The response of patients with dystonia to pallidal procedures is not well understood. In this study, we assessed the postoperative outcome of patients with primary and secondary dystonia undergoing pallidotomy or pallidal deep brain stimulation.

Methods: Fifteen patients with dystonia had pallidal surgery (lesions or deep brain stimulation).

Deep brain stimulation for Parkinson's disease dissociates mood and motor circuits: a functional MRI case study.

Behavioral disturbances have been reported with subthalamic (STN) deep brain stimulation (DBS) treatment in Parkinson's disease (PD). We report correlative functional imaging (fMRI) of mood and motor responses induced by successive right and left DBS. A 36-year-old woman with medically refractory PD and a history of clinically remitted depression underwent uncomplicated implantation of bilateral STN DBS.