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M Saling

Publications and source records attributed to M Saling.

16 recordsLinked to original sources
PubMed1992

Reaching behavior in the rat: absence of forelimb peripheral input.

In order to test whether peripheral input from a moving forelimb is essential for reaching in rats, the effects of dorsal rhizotomy C5-Th2 were examined. Rats were trained to reach for a food pellet in the horizontal tube or on a tray. Reaching attempts before and after bilateral forelimb deafferentation were monitored by continual recording using magnetic induction. Deafferented animals were able to initiate and generate the motor program of reaching, but modulation of its ongoing execution was lost. Peripheral input from moving forelimb was necessary for the effective performance of grasping; the duration of the manipulative part of reaching was significantly prolonged and the success of grasping was markedly decreased. Also, the aiming of forelimb was impaired, probably by disturbing of body forelimb postural coordination. No significant changes were found in the execution of forelimb protraction. It is concluded that somesthetic feedback is not required for execution of forelimb protraction, but it is necessary for grasping.

Animals↗
PubMed1992

[The effect of head position and functional status of the cervical spine on body sway in the upright posture].

In 30 subjects (16 men and 14 women) stabilometry was used to investigate the stability of posture with closed eyes and different positions of the head (backward, forward, right and left turn). Cervical spine mobility of the subjects studied was determined by vertebrogenic examination. The maximum backward extension of the head was found to reduce most markedly posture stability. Correlation analysis revealed a relationship between the functional state of the cervical spine and the degree of posture stability impairment induced by backward extension of the head, with the impairment being more pronounced in the forward-backward direction. The obtained results show that changes in the quality of proprioceptive information from the cervical spine region are also involved in determining the stability level of upright posture. The findings imply that posture with backward extension of the head can be used as a loading test for detecting ataxia of cervical origin.

Adult↗
PubMed1991

Mechanisms and clinical features of internal watershed infarction.

The mechanism of internal carotid watershed cerebral infarction is not well understood, but the phenomenon has been described in association with carotid occlusive disease, and more recently with distal middle cerebral artery occlusion beyond the origin of the lenticulostriate branches. The clinical correlates of these changes have not yet been described. We present 5 patients in whom acute internal watershed infarction had occurred, and correlate the clinical, neuropsychological and 99mTc-HMPAO SPECT (Single Photon Emission Computed Tomography using 99mtechnetium-hexamethylpropylene amine oxime) cerebral perfusion findings. Four patients had distal middle cerebral artery occlusion demonstrated on angiography, and one showed profound hemispheric depression in cerebral perfusion with only a small area of infarction. We have concentrated on the mechanism of distal middle cerebral artery occlusion to describe the "arc" of the watershed zone created. We propose that internal watershed infarcts can further be subdivided into anterior and posterior subtypes, outline the vascular territories involved, and propose an overall classification of cerebral watershed infarction.

Adult↗
PubMed1991

Visual and quantitative analysis of interictal SPECT with technetium-99m-HMPAO in temporal lobe epilepsy.

Interictal 99mTc-HMPAO SPECT images were compared to ictal EEG localization in 51 patients with intractable temporal lobe epilepsy to determine their usefulness for preoperative seizure focus localization. Both quantified temporal lobe asymmetry and blinded visual detection of temporal lobe hypoperfusion were employed. Visual analysis detected ipsilateral hypoperfusion in 18 (39%) of the 46 patients with a unilateral focus and contralateral hypoperfusion in 3. None of the five patients with bitemporal foci had unilateral hypoperfusion. The positive predictive value of unilateral temporal lobe hypoperfusion was 86% (18/21). Quantified anterior temporal lobe asymmetry, greater than a previously derived normal range, correctly identified the focus in 22 (48%) but gave the wrong side in 5, resulting in a predictive value of 81%. The degree of asymmetry correlated inversely with age of seizure onset, but not with other clinical parameters, histology, or verbal and nonverbal memory. The usefulness of interictal 99mTc-HMPAO SPECT for pre-operative seizure focus localization is limited by low sensitivity when performed with a conventional rotating gamma camera. This suggests that ictal or immediate postictal imaging may be necessary for this purpose.

Adult↗
PubMed1991

[Quantitative evaluation of disorders of upright posture using stabilometry].

The authors examined, using the stabilometric method, 14 patients with lesions of the cerebellum, vestibular system and cerebral hemispheres (hemiparetics). Quantitative evaluation of the stability of posture was done using 7 parameters under four conditions: with open eyes, with closed eyes, with additional visual feedback and standing on a 10 cm foam rubber with closed eyes. In patients with a vestibular lesion the authors observed more frequent elevated values in a lateral direction, a marked destabilization of the posture on the foam rubber and effective use of the added visual feedback. Cerebellar patients were unable to use effectively the visual biofeedback for stabilization of posture. They were characterized by an obvious increase of stabilometric parameters in both directions and under all circumstances. The visual biofeedback had a different effect on maintenance of the upright position in hemiparetic patients. Stabilometry enables the authors to quantify posture and to record different characteristics of postural ataxias.

Adolescent↗
PubMed1990

Adjunctive therapy with bromocriptine in Parkinson's disease.

Patients with moderately severe Parkinson's disease complicated by the adverse effects of chronic levodopa use benefited from the addition of bromocriptine (Parlodel; Sandoz) in doses up to 26 mg daily, which allowed an approximate 30% reduction of levodopa dose. This resulted in a significant decrease in the amount of levodopa side-effects while maintaining or improving the original parkinsonian clinical stage. Increased effectiveness in these patients was not associated with increased dosage beyond 25-30 mg daily. When the doses of bromocriptine were increased slowly, the adverse reactions were minor and usually transient.

Adult↗
PubMed1990

Analysis of reaching in the rat by the continuous movement monitoring, utilizing the law of magnetic induction.

Successful and unsuccessful reaching attempts in rats were analysed with the aim of resolving the question of the programming of reaching movement. The course of movement was monitored continuously by a method based on the law of magnetic induction. The study of reaching showed that the forelimb extension had the same time course characteristics in both cases of reaching attempts and displayed features of preprogrammed ballistic movement. The course of the consecutive phases (grasping, forelimb flexion) showed differences between successful and unsuccessful attempts and also between individual successful attempts. The variability of the course of grasping and forelimb flexion indicates that a peripheral feedback participates in regulation of its performance and that the information on grasping the pellet is decisive for the subsequent performance of reaching. Reaching as a whole cannot be considered as a preprogrammed ballistic movement, but some of its components correspond to this pattern.

Animals↗
PubMed1989

Continual monitoring of reaching in rat using magnetic induction law.

A method enabling the continual monitoring of movement has been developed based on the law of magnetic induction. The method was concretely applied in the handedness model of the rat. A sensing loop was implanted under the forearm skin of a rat. Electric voltage was induced by the movement of the sensing loop in a DC magnetic field. This voltage is proportional to the movement velocity and its polarity to the direction. The continuous character of the movement record allows convenient analysis and a more exact correlation with the bioelectric concomitants of the movement.

Animals↗
PubMed1988

Inverted vision after frontal lobe disease.

A case of bifrontal abscesses is reported. The patient claimed that he sometimes saw the world as if it were upside-down. A review of the literature reveals that, since 1805, 21 similar cases have been documented. The present case is unusual in that the neuropsychological status of the patient is investigated in some detail, and in that it seems to be the first report of inverted vision in a case of frontal lobe disease.

Brain Abscess↗
PubMed1986

On psychoanalysis and neuroscience: Freud's attitude to the localizationist tradition.

This study examines the relationship between psychoanalysis and neuroscience. It argues that the Project, the traditional starting-point for such an examination, provides few substantial links between Freud's neurological and psychoanalytic careers. The neurological model that the Project endorsed was not derived from Freud's formal neurological education, as has so often been assumed. It was based, instead, on the Jacksonian model that he developed in 'On aphasia' in 1891. 'On aphasia' appears to be the real 'missing link' between Freud's neurological and psychological years. The fundamental principles that it endorsed provided the framework within which psychoanalysis developed. After Freud's death, Luria developed the science of dynamic neuropsychology, which is based on the same fundamental neurological assumptions as 'On aphasia'. Dynamic neuropsychology approaches brain functioning in a way that would have been entirely acceptable to Freud. Considering the deep-rooted compatibility between Luria's neuropsychology and Freud's psychoanalysis, it would be beneficial for both sciences if they were to collaborate on issues of common interest. This makes Freud's lifelong ambition that psychoanalysis be rejoined with neuroscience a very real possibility.

Aphasia↗
PubMed1986

Compensation effect of visual biofeedback in upright posture control.

The effectivity of the compensatory role of visual biofeedback in cases of decreased stability of upright posture has been analysed. The deterioration of stance was modelled by a subject standing on a soft surface and with additional weight load on the body. The influence of visual biofeedback was positive only for the compensation of decreased stability of upright posture caused by artificially increased body weight of the subject. The compensatory effectivity of visual biofeedback in stabilization of upright posture during stance on a soft surface was practically negligible. The results have shown that effective compensation of the destabilizing effect by visual biofeedback in human upright posture was possible only when the activity and efficiency of efferent-action part of the postural system remained unchanged.

Adult↗
PubMed1985

Activity changes in nucleus reticularis gigantocellularis in relation to skilled forelimb movement in rats.

Adult hooded rats were trained to reach for food pellets into a narrow plexiglass tube and the movement of the preferred forelimb was photo-electrically detected. Multiple unit activity (MUA) or single unit activity in n. reticularis gigantocellularis (NGC) was recorded during reaching. Depression of MUA was observed about the onset of the forepaw movement and lasted during its execution. There was a correlation between MUA changes and the depression of activity of individual neurons observed in a part of NGC.

Action Potentials↗