The right hemisphere: neuropsychological functions

1986 ◽  
Vol 64 (5) ◽  
pp. 693-704 ◽  
Author(s):  
Kenneth M. Heilman ◽  
Dawn Bowers ◽  
Edward Valenstein ◽  
Robert T. Watson
Keyword(s):  
Emotional Disorders ◽  
Right Hemisphere ◽  
Content Type ◽  
Reading And Writing ◽  
The Past ◽  
Right Hemisphere Damage ◽  
Right Hemisphere Dysfunction ◽  
Neuropsychological Functions ◽  
The Right ◽  
Fine Print

✓ In the past two to three decades, clinicians and neuroscientists have been studying the functions of the right hemisphere. Neither hemisphere seems to be dominant in the absolute sense. Each appears to be specialized and is dominant for different functions. However, most functions require the cooperation of both hemispheres. When one is damaged, the other can often compensate for the damaged one. Lesions of the left hemisphere are associated with language (speech, reading, and writing) and praxic disorders, and lesions of the right hemisphere can result in visuospatial, attentional, and emotional disorders. The authors review some of the major behavioral disorders associated with right hemisphere dysfunction and concentrate on three major types of disorders — visuospatial, attentional, and emotional. Although not all the behavioral defects associated with right hemisphere damage can be subgrouped under these three types, they are the ones most often associated with right hemisphere lesions.

Brain kininogen following experimental brain injury: evidence for a secondary event

1989 ◽  
Vol 71 (3) ◽  
pp. 437-442 ◽  
Author(s):  
Earl F. Ellis ◽  
Julie Chao ◽  
Marcia L. Heizer
Keyword(s):  
Brain Injury ◽  
Right Hemisphere ◽  
Kinin System ◽  
Content Type ◽  
Cerebrovascular Function ◽  
Pressure Injury ◽  
Cerebral Arterioles ◽  
The Right ◽  
Kallikrein Kinin System ◽  
Fine Print

✓ Previous studies have shown that following experimental brain injury cerebral arterioles dilate and display endothelial lesions and reduced responsiveness to hypocapnia. These abnormalities are caused by cyclooxygenase-dependent free radical generation. There is evidence that the kallikrein-kinin system may in part stimulate the cyclooxygenase-dependent damage since bradykinin is a powerful stimulator of prostaglandin formation and it has recently been shown that a specific kinin receptor blocker decreases the arteriolar abnormalities caused by injury. In order to further examine the hypothesis that the kallikrein-kinin system is important in inducing damage, rat brain tissue was examined for kininogen, the precursor of kinins, at 10 minutes and 1, 3, 6, 15, 24, 48, and 72 hours after injury. A fluid-percussion brain injury device was attached over the right cerebral cortex of rats and a 1.6-atmosphere pressure injury was administered. The kininogen content was determined by a radioimmunoassay procedure in tissues which were free of intravascular blood. After injury, bleeding was confined mainly to the right hemisphere. The kininogen content in the right hemisphere was significantly elevated by one hour after injury, continued to rise until 15 hours after injury, then was significantly decreased by 2 days after injury. In the left hemisphere, kininogen was significantly elevated at 1 hour postinjury, returned toward control levels over the 3- to 6-hour period after injury, then was again elevated at 15 hours after injury. These studies also show that brain water and cerebrovascular permeability were greater at 15 hours postinjury than at earlier time points. The data further support a role for the kallikrein-kinin system in brain injury and, when considered with the results of other studies, suggest that a secondary event is occurring in the 12- to 24-hour period after neural injury. The authors hypothesize that this secondary event is related to endothelial and vascular repair and may be important for the return of normal cerebrovascular function.

Parenchymal cerebrospinal fluid extravasation as a complication of computerized tomography

1980 ◽  
Vol 52 (1) ◽  
pp. 113-115 ◽  
Author(s):  
Harold L. Rekate
Keyword(s):  
Cerebrospinal Fluid ◽  
Computerized Tomography ◽  
Right Hemisphere ◽  
Neurological Dysfunction ◽  
Ventricular Catheter ◽  
Content Type ◽  
Fluid Extravasation ◽  
Computerized Tomographic Study ◽  
The Right ◽  
Fine Print

✓ A case is presented in which neurological deterioration occurred during a computerized tomographic study. Total hemispheric dysfunction was seen in a patient with a postoperative suboccipital pseudomeningocele, whose head was wrapped in a compressive water bag. Cerebrospinal fluid was forced under pressure into the parenchyma of the right hemisphere, around a ventricular catheter. The neurological dysfunction resolved promptly with shunting.

Combined endovascular embolization and surgery in the management of cerebral arteriovenous malformations: experience with 101 cases

1991 ◽  
Vol 75 (6) ◽  
pp. 856-864 ◽  
Author(s):  
Fernando Viñuela ◽  
Jacques E. Dion ◽  
Gary Duckwiler ◽  
Neil A. Martin ◽  
Pedro Lylyk ◽  
...  
Keyword(s):  
Arteriovenous Malformations ◽  
Right Hemisphere ◽  
Endovascular Embolization ◽  
Pulmonary Complications ◽  
Surgical Removal ◽  
Cerebral Arteriovenous Malformations ◽  
Content Type ◽  
Grade Ii ◽  
The Right ◽  
Fine Print

✓ The authors describe their experience with 101 cerebral arteriovenous malformations (AVM's) treated by endovascular embolization followed by surgical removal. Fifty-three patients presented with intracranial hemorrhage and 35 had seizures. Based on the classification of Spetzler and Martin, two AVM's were Grade I, 13 were Grade II, 26 were Grade III, 43 were Grade IV, and 17 were Grade V, Fifty-six AVM's were in the right hemisphere, 28 were in the left hemisphere, 12 were in the corpus callosum, and five involved the cerebellum. In 50 cases, presurgical obliteration of 50% to 75% of the AVM nidus was achieved by embolization, and in 31 cases this percentage increased to between 75% and 90%. In 97 (96%) patients, complete surgical removal of the AVM was obtained. Morbidity resulting from preoperative endovascular embolization was classified as mild in 3.9% of the cases, moderate in 6.9%, and severe in 1.98%. The death rate related to embolization was 0.9%. The immediate postsurgical morbidity was classified as mild in 5.9% of the cases, moderate in 10.8%, and severe in 5.9%. The overall long-term morbidity was mild in 5.9% of the cases, moderate in 6.9%, and severe in 1.98%. Two patients (1.98%) died due to intractable intraoperative hemorrhage and two (1.98%) as a result of postsurgical pulmonary complications.

Verbal comprehension deficits after right hemisphere damage

1980 ◽  
Vol 1 (3) ◽  
pp. 279-294 ◽  
Author(s):  
Daniel B. Hier ◽  
Joni Kaplan
Keyword(s):  
Educational Attainment ◽  
Sentence Comprehension ◽  
Right Hemisphere ◽  
Vocabulary Test ◽  
Verbal Comprehension ◽  
Visuospatial Deficits ◽  
Control Subjects ◽  
Right Hemisphere Damage ◽  
The Right ◽  
Grammatical Sentence

ABSTRACTWe have compared the verbal comprehension abilities of 34 right hemisphere damaged patients to 16 hospitalized control subjects of comparable age and educational attainment. The right hemisphere damaged patients performed as well as the control subjects on a vocabulary test, but were impaired in their ability to interpret proverbs and comprehend logico-grammatical sentences. Impairment on the proverbs test was the result of a decrease in the number of abstract interpretations, whereas impairment on the logico-grammatical sentence comprehension test was related to difficultes in grasping spatial and passive relationships. These comprehension impairments tended to correlate with visuospatial deficits and hemianopia, but not with the degree of hemiparesis or the presence of sensory extinction. Patients with anterior right hemisphere damage performed better on the logico-grammatical sentence conprehension test than patients with posterior damage. A variety of factors probably contribute to these verbal deficits including impaired intellect, inattention, an inability to grasp spatial relationships, and difficulties in manipulating the inner schemata of language.

Malignant astrocytoma following radiotherapy of a craniopharyngioma

1978 ◽  
Vol 48 (4) ◽  
pp. 622-627 ◽  
Author(s):  
Richard L. Sogg ◽  
Sarah S. Donaldson ◽  
Craig H. Yorke
Keyword(s):  
Experimental Evidence ◽  
Temporal Lobe ◽  
Malignant Astrocytoma ◽  
Content Type ◽  
Suprasellar Region ◽  
The Right ◽  
Fine Print

✓ A 9-year-old schoolgirl received 6007 rads to the suprasellar region for craniopharyngioma. Five years later, a malignant astrocytoma developed in the right temporal lobe. We cite clinical and experimental evidence to support our suspicion that the glioma may have been induced by radiation.

A new rat model of chronic cerebral hypoperfusion associated with arteriovenous malformations

2002 ◽  
Vol 97 (5) ◽  
pp. 1198-1202 ◽  
Author(s):  
Jian Hai ◽  
Meixiu Ding ◽  
Zhilin Guo ◽  
Bingyu Wang
Keyword(s):  
Electron Microscopy ◽  
Animal Model ◽  
Arteriovenous Malformations ◽  
Perfusion Pressure ◽  
Chronic Cerebral Hypoperfusion ◽  
Cerebral Hypoperfusion ◽  
Model Group ◽  
Content Type ◽  
The Right ◽  
Fine Print

Object. A new experimental model of chronic cerebral hypoperfusion was developed to study the effects of systemic arterial shunting and obstruction of the primary vessel that drains intracranial venous blood on cerebral perfusion pressure (CPP), as well as cerebral pathological changes during restoration of normal perfusion pressure. Methods. Twenty-four Sprague—Dawley rats were randomly assigned to either a sham-operated group, an arteriovenous fistula (AVF) group, or a model group (eight rats each). The animal model was readied by creating a fistula through an end-to-side anastomosis between the right distal external jugular vein (EJV) and the ispilateral common carotid artery (CCA), followed by ligation of the left vein draining the transverse sinus and bilateral external carotid arteries. Systemic mean arterial pressure (MAP), draining vein pressure (DVP), and CPP were monitored and compared among the three groups preoperatively, immediately postoperatively, and again 90 days later. Following occlusion of the fistula after a 90-day interval, blood—brain barrier (BBB) disruption and water content in the right cortical tissues of the middle cerebral artery territory were confirmed and also quantified with transmission electron microscopy. Formation of a fistula resulted in significant decreases in MAP and CPP, and a significant increase in DVP in the AVF and model groups. Ninety days later, there were still significant increases in DVP and decreases in CPP in the model group compared with the other groups (p < 0.05). Damage to the BBB and brain edema were noted in animals in the model group during restoration of normal perfusion pressure by occlusion of the fistula. Electron microscopy studies revealed cerebral vasogenic edema and/or hemorrhage in various amounts, which correlated with absent astrocytic foot processes surrounding some cerebral capillaries. Conclusions. The results demonstrated that an end-to-side anastomosis between the distal EJV and CCA can induce a decrease in CPP, whereas a further chronic state of cerebral hypoperfusion may be caused by venous outflow restriction, which is associated with perfusion pressure breakthrough. This animal model conforms to the basic hemodynamic characteristics of human cerebral arteriovenous malformations.

Cerebrovascular characterization of clazosentan, the first nonpeptide endothelin receptor antagonist clinically effective for the treatment of cerebral vasospasm. Part I: Inhibitory effect on endothelinA receptor—mediated contraction

2005 ◽  
Vol 102 (6) ◽  
pp. 1101-1107 ◽  
Author(s):  
Hartmut Vatter ◽  
Michael Zimmermann ◽  
Veronika Tesanovic ◽  
Andreas Raabe ◽  
Lothar Schilling ◽  
...  
Keyword(s):  
Receptor Antagonist ◽  
Cerebral Vasospasm ◽  
Isometric Force ◽  
Inhibitory Effect ◽  
Affinity Constant ◽  
Dependent Manner ◽  
Content Type ◽  
The Right ◽  
Fine Print

Object. The central role of endothelin (ET)—1 in the development of cerebral vasospasm after subarachnoid hemorrhage is indicated by the successful treatment of this vasospasm in several animal models by using selective ETA receptor antagonists. Clazosentan is a selective ETA receptor antagonist that provides for the first time clinical proof that ET-1 is involved in the pathogenesis of cerebral vasospasm. The aim of the present investigation was, therefore, to define the pharmacological properties of clazosentan that affect ETA receptor—mediated contraction in the cerebrovasculature. Methods. Isometric force measurements were performed in rat basilar artery (BA) ring segments with (E+) and without (E−) endothelial function. Concentration effect curves (CECs) were constructed by cumulative application of ET-1 or big ET-1 in the absence or presence of clazosentan (10−9, 10−8, and 10−7 M). The inhibitory potency of clazosentan was determined by the value of the affinity constant (pA2). The CECs for contraction induced by ET-1 and big ET-1 were shifted to the right in the presence of clazosentan in a parallel dose-dependent manner, which indicates competitive antagonism. The pA2 values for ET-1 were 7.8 (E+) and 8.6 (E−) and the corresponding values for big ET-1 were 8.6 (E+) and 8.3 (E−). Conclusions. The present data characterize clazosentan as a potent competitive antagonist of ETA receptor—mediated constriction of the cerebrovasculature by ET-1 and its precursor big ET-1. These functional data may also be used to define an in vitro profile of an ET receptor antagonist with a high probability of clinical efficacy.

scholarly journals Sensory deficits in ipsilesional upper-extremity in chronic stroke patients

2015 ◽  
Vol 73 (10) ◽  
pp. 834-839 ◽  
Author(s):  
Núbia Maria Freire Vieira Lima ◽  
Karina Cândido Menegatti ◽  
Érica Yu ◽  
Natália Yumi Sacomoto ◽  
Thais Botossi Scalha ◽  
...  
Keyword(s):  
Right Hemisphere ◽  
Thermal Sensation ◽  
Chronic Stroke ◽  
Sensory Loss ◽  
Stroke Patients ◽  
Sensory Assessment ◽  
Sensory Deficits ◽  
Left Handed ◽  
Right Hemisphere Damage ◽  
The Right

Objective To investigate somatosensory deficits in the ipsilesional wrist and hand in chronic stroke patients and correlate these deficits with contralesional sensorimotor dysfunctions, functional testing, laterality and handedness.Methods Fifty subjects (twenty-two healthy volunteers and twenty-eight stroke patients) underwent evaluation with Semmes-Weinstein monofilaments, the sensory and motor Fugl-Meyer Assessment, the Nottingham Sensory Assessment in both wrists and hands and functional tests.Results Twenty-five patients had sensory changes in the wrist and hand contralateral to the stroke, and eighteen patients (64%) had sensory deficits in the ipsilesional wrist and hand. The most significant ipsilesional sensory loss was observed in the left-handed patients. We found that the patients with brain damage in the right hemisphere had better scores for ipsilesional tactile sensation.Conclusions A reduction in ipsilesional conscious proprioception, tactile or thermal sensation was found in stroke subjects. Right hemisphere damage and right-handed subjects had better scores in ipsilesional tactile sensation.

Coerced training of the nondominant hand resulting in cortical reorganization: a high-field functional magnetic resonance imaging study

2004 ◽  
Vol 101 (2) ◽  
pp. 310-313 ◽  
Author(s):  
Tsutomu Nakada ◽  
Yukihiko Fujii ◽  
Ingrid L. Kwee
Keyword(s):  
Magnetic Resonance Imaging ◽  
High Field ◽  
Cortical Reorganization ◽  
Functional Magnetic Resonance ◽  
Resonance Imaging ◽  
Content Type ◽  
Hand Motion ◽  
Left Handed ◽  
The Right ◽  
Fine Print

Object. The authors investigated brain strategies associated with hand use in an attempt to clarify genetic and nongenetic factors influencing handedness by using high-field functional magnetic resonance imaging. Methods. Three groups of patients were studied. The first two groups comprised individuals in whom handedness developed spontaneously (right-handed and left-handed groups). The third group comprised individuals who were coercively trained to use the right hand and developed mixed handedness, referred to here as trained ambidexterity. All trained ambidextrous volunteers were certain that they were innately left-handed, but due to social pressure had modified their preferred hand use for certain tasks common to the right hand. Although right-handed and left-handed volunteers displayed virtually identical cortical activation, involving homologous cortex primarily located contralateral to the hand motion, trained ambidextrous volunteers exhibited a clearly unique activation pattern. During right-handed motion, motor areas in both hemispheres were activated in these volunteers. During left-handed motion, the right supplemental motor area and the right intermediate zone of the anterior cerebellar lobe were activated significantly more frequently than observed in naturally right-handed or left-handed volunteers. Conclusions. The results provide strong evidence that cortical organization of spontaneously developed right- and left-handedness involves homologous cortex primarily located contralateral to the hand motion, and this organization is likely to be prenatally determined. By contrast, coerced training of the nondominant hand during the early stages of an individual's development results in mixed handedness (trained ambidexterity), indicating cortical reorganization.

Minds and brains: angels, humans, and brutes

1982 ◽  
Vol 57 (3) ◽  
pp. 309-315
Author(s):  
Mortimer J. Adler
Keyword(s):  
Nervous System ◽  
Animal Behavior ◽  
Personal Experience ◽  
Human Beings ◽  
Content Type ◽  
The Past ◽  
Wide Range ◽  
Conceptual Thought ◽  
The Brain ◽  
Fine Print

✓ In his 1982 Cushing oration, a distinguished philosopher, author, and discerning critic presents a distillate of his phenomenally wide range of personal experience and his familiarity with the great books and teachers of the present and the past. He explores the differences and relationships between human beings, brute animals, and machines. Knowledge of the brain and nervous system contribute to the explanation of all aspects of animal behavior, intelligence, and mentality, but cannot completely explain human conceptual thought.

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