Dopa-responsive pseudo-orthostatic tremor in parkinsonism.

In four patients an inabilitating standing tremor appeared years before that parkinsonian symptoms were evidenced. This tremor was refractory to gabapentin and dramatically responded to Levodopa administration. Its dominant frequency was 6.2 to 6.9 Hz with sporadic subharmonics at 8 to 18 Hz. Three patients were affected by different genetic mutations (Park 2, Park 6, mtDNA deletion) in one no genetic or metabolic alterations could be evidenced. All patients had dopamine transporter abnormalities. We suggest that the term "Pseudo-Orthostatic Tremor" could be used to define this Dopa responsive, 6 to 7 Hz standing tremor.     

Dopa-responsive parkinsonism phenotype of spinocerebellar ataxia type 2.

We report on 2 brothers, Patients 1 and 2, who presented with a similar clinical syndrome consisting of resting tumor, bradykinesia, rigidity, and dysarthria at the ages of 40 and 43 years, respectively. An excellent response to levodopa therapy was observed throughout the disease course. No gait or limb ataxia, slow saccades, or decreased tendon reflexes were detected, but unsteadiness of gait with propulsion developed recently in Patient 1 approximately 25 years after disease onset. Magnetic resonance imaging demonstrated mild atrophy of the pons and cerebellum in Patient 1 and cerebellar atrophy in Patient 2. Expanded CAG repeats, numbering 36, in one allele of the ataxin-2 gene were identified in Patient 1 only; his brother was not available for this investigation. With [(99m)Tc]TRODAT-1 single photon emission computed tomography of the brain, a significant bilateral and asymmetrical reduction of striatal dopamine transporters was found in Patient 1 compared to healthy controls. This bilateral reduction of striatal dopamine transporters resembled that observed in a set of controls with Parkinson's disease who had asymmetrical impairment. These results suggest that patients with familial parkinsonism who present with typical Parkinson's disease should be screened for the genetic defect of spinocerebellar ataxia type 2. The presynaptic impairment of nigrostriatal function is very likely to be the reason for levodopa responsiveness.     

Adaptation to speaker's voice in right anterior temporal lobe

Little is known on how voices are represented in the brain. We used fMRI to investigate whether parts of auditory cortex would be sensitive to the repetition of a speaker's voice. Subjects were scanned while passively listening to spoken syllables, presented in blocs in which either syllable or speaker were repeated. Only one cortical region, located in the anterior part of the right superior temporal sulcus (STS), responded differently to the two conditions: activation relative to the silent baseline was significantly reduced when syllables were spoken by a single voice than when they were spoken by different voices. This result suggest that the right anterior STS plays an important role in the representation of individual voices.     

The right temporal lobe variant of frontotemporal dementia

The right temporal variant of frontotemporal lobar degeneration (Rtv-FTLD) is a focal degenerative condition affecting predominantly the right temporal lobe. The aim of this study was to further characterize the profile of cognitive impairment and the neuroanatomical basis of Rtv-FTLD patients without behavioural disturbances. A group of three patients with this syndrome had a detailed neuropsychological assessment, along with Voxel-Based Morphometry (VBM) of their brain to determine location of cortical atrophy. VBM analyses showed a pattern of atrophy that was predominant in the right hemisphere and concerned primarily the right anterior temporal lobe region. Patients carried out a test of famous people in which their ability to recognize, name and provide semantic information about famous persons from their faces, their voices and their names was investigated. They all showed a severe defect in recognizing, naming and identifying famous people irrespective of modality. Therefore, their inability to recognize famous people resulted from a multimodal defect (semantic). These results highlight the semantic nature of the defect, and suggest that the anterior right temporal lobe may have a prominent role in processing person-based semantic knowledge. This study helps in further understanding the neuropsychological profile of patients with Rtv-FTLD.     

Visual learning deficits in nonresected patients with right temporal lobe epilepsy.

A visual learning test Diagnostikum für Zerebralsch?den (DCS) was revised and applied to three matched patient groups defined by interictal and ictal EEG findings: 24 patients with left temporal lobe epilepsy (LTE), 19 patients with right temporal lobe epilepsy (RTE) and 34 patients with a bitemporal epileptic involvement (BTE). Fifty seven healthy subjects served as controls. Performance on a measure of sustained attention and visual construction was also assessed. Results were as follows: (1) In contrast to controls and LTE patients, patients with right temporal epileptic involvement (RTE/BTE) showed a significantly reduced immediate recall as well as a reduced learning capacity and mean learning performance. (2) Patients made significantly more errors than controls, with RTE patients exhibiting the most visuo-spatial errors. (3) RTE/BTE patients additionally showed impaired performances on visuo-construction, but when visual construction scores were used as covariate, they did not diminish the strong group effects upon learning. (4) Attentional deficits were independent from memory deficits and rather reflected the bitemporal extention of epilepsy. As a conclusion, the data suggest an impairment of visual-spatial consolidation processes in patients with right temporal lobe epilepsy.     

Panic attacks and temporal lobe seizures associated with a right temporal lobe arteriovenous malformation: case report

A 33-year-old woman developed temporal lobe seizures and was found to have a right frontotemporal arteriovenous malformation. She subsequently developed panic attacks that could be induced by lactate infusion and were successfully treated with imipramine. The possibility that the panic attacks were caused by a structural lesion of the right temporal lobe is discussed.     

Progressive degeneration of the right temporal lobe studied with positron emission tomography.

A 79 year old man with a twelve year progressive history of prosopagnosia and recent naming difficulty, in whom other intellectual skills were preserved, is described. Positron emission tomography (PET) revealed an area of right temporal lobe hypometabolism, with an additional area of less severe hypometabolism at the left temporal pole. This may represent an example of progressive focal cortical degeneration similar to that associated with primary progressive dysphasia, but affecting the right temporal lobe.     

Neuromagnetic auditory evoked responses after a stroke in the right temporal lobe.

Auditory evoked magnetic fields were recorded with a 24-SQUID magnetometer on a patient with a vascular lesion in the right auditory cortex and its vicinity. The contralateral transient 100 ms response (N100m) was absent over the damaged side, with no recovery within 16 months. Responses were normal over the healthy side. The responses to a binaural click train where interaural delays caused the perception of a shifting sound source; responses were again normal over the left side. Ipsilateral tones elicited N100m over the normal hemisphere but with smaller amplitude and longer latency than in healthy subjects. We suggest that ipsilateral responses are triggered by ipsilateral afferents but are significantly modified by excitatory callosal connections which did not work in our patient.     

Adaptive visual memory reorganization in right medial temporal lobe epilepsy

Purpose: We investigated functional reorganization mechanisms of the human medial temporal lobe (MTL) for episodic memory, in patients suffering from medial temporal lobe epilepsy (MTLE) with hippocampal sclerosis (HS).
Methods: We used functional magnetic resonance imaging (fMRI) to measure brain activity changes during matched episodic encoding tasks of abstract words (Verbal) and line drawings (Visual), in patients with unilateral right MTLE undergoing presurgical evaluation and healthy controls.
Results: As expected, a significant interaction between material type and the side of MTL activity was present in the control group, with preferential involvement of the left hippocampus in verbal encoding and the right parahippocampal region in visual encoding. When compared with controls, right MTLE patients with intact performance activated a region in the left hippocampus more during visual encoding, which resulted in an interaction between group and hemisphere. Importantly, an effect of memory performance on visual encoding activity was observed in the patients, with greater engagement of the left MTL being associated with higher recognition scores. Interestingly, activity in the left MTL also depended on the epileptic seizure frequency, suggesting a role for this clinical parameter in the recruitment of contralateral regions.
Discussion: Taken together, these results indicate functional reorganization of the MTLs in right HS, through transfer of function from the right to the left hemisphere, and strongly suggest an adaptive role for such reorganization mechanism in supporting preserved visual memory.     

Motor amusia following a right temporal lobe hemorrhage--a case report

A 65-year-old female was admitted to our hospital because of left hemiparesis with sudden onset one week before. She was congenitally right-handed. She had been a teacher of Japanese string instrument (samisen) playing and been able to sing Japanese traditional songs well. A tape on which she had recorded her songs one year before the admission also proved her to be a good singer. Neurological examination on admission revealed almost normal findings except for minimal weakness in her left hand fingers. Right temporal lobe hemorrhage was revealed by CT scan. One month after the admission, she complained that she was unable to sing her songs and to play samisen as she used to do. Her intelligence was normal (WAIS VIQ116, PIQ108) and there were no abnormal findings as follows: aprosodia, aphasia, agraphia, memory disturbance, agnosia and ideational, ideomotor, constructional or limb-kinetic apraxia. She could point out her errors while singing. However, musical receptive function was slightly disturbed with tonal memory in Seashore test. When she was asked to sing a song without any instrumental support, she hummed a melody occasionally with wrong pitch, but rhythmically. After hearing a song she knew well, she reproduced it with slight improvement. With the vocal or the instrumental accompaniment, she could sing fairly well. She had some mistakes of pitch while playing a samisen. MRI was performed one year and a half after the brain hemorrhage. It displayed a thin linear of hematoma in the white matter of the right upper temporal and transverse gyrus. It was proved in our case that motor amusia with minimal musical receptive dysfunction could appear following a cerebral lesion and musical function might be independent of intelligence or verbal function.     

Visual hypoemotionality and prosopagnosia associated with right temporal lobe isolation

Emotional hyporeactivity to visual stimuli (so-called visual hypoemotionality) was observed in a 71-yr-old woman following a cerebral infarction in the territory of the posterior cerebral arteries. Other visual disturbances included severe prosopagnosia, dense left hemianopia and mild left hemineglect. There was neither object agnosia nor any involvement of language, memory or intellectual functions. Hypoemotionality was found only for visual stimuli, since auditory and tactile modalities were totally spared, suggesting a visual-limbic disconnection mechanism. From CT data, and referring to previous evidence suggesting a right-hemisphere prevalence for emotional functions, it is postulated that the right occipital lesion, leading to a total right temporal lobe isolation, was mainly responsible for the patient's emotional disturbances.     

Obsessive-compulsive disorder secondary to a right parietal lobe haemorrhage: a case report

This case report presents a 39-year-old previously healthy man, who presented with typical obsessive-compulsive disorder and neurological symptoms and was found to have a right parietal lobe haemorrhage. His psychiatric and neurological recovery was associated with a complete radiological resolution. This report is consistent with recent imaging studies implicating the parietal lobe in the pathogenesis of obsessive-compulsive disorder and adds haemorrhage to the list of organic cerebral lesions causally associated with this disorder.     

Ictal kissing and religious speech in a patient with right temporal lobe epilepsy.

We report the case of a 25-year-old female patient with intractable complex partial seizures characterized by repetition of certain religious statements and a rather compulsive kissing behavior. Presurgical evaluation revealed a right-sided, mesial temporal focus and hippocampal sclerosis on MRI. After selective amygdalohippocampectomy, she has only occasional auras. Her rare and peculiar ictal manifestations are discussed in the context of semiology and pathogenesis. [Published with videosequences].