Sex similarities in verbal and performance IQ deficits following unilateral cerebral lesions.

Investigated whether men and women produce similar Verbal IQ and Performance IQ patterns following unilateral cerebral lesions. Ss included 24 women (mean age 43.96 yrs) and 24 men (mean age 45.08 yrs) with independent neurological evidence of neoplastic or vascular lesions of the right cerebral hemisphere, 24 women (mean age 47.88 yrs) and 24 men (mean age 47.50 yrs) with such lesion evidence of the left cerebral hemisphere, and 14 female (mean age 46.43 yrs) and 14 male (mean age 45.50 yrs) controls. Each group was equated for education, lesion site, severity, chronicity, and etiology. Ss were administered the Wechsler-Bellevue Intelligence Scale, and differences in Verbal and Performance IQ values were compared. Contrary to reports in the literature, no consistent evidence of Sex?×?Lesioned Hemisphere interactions was found. Differences in the lateralization effects between men and women were not reflected in direction or pattern but only in magnitude, arguing against a theory of differential cognitive lateralization according to sex. (15 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Behavioral deficits after distal focal cerebral ischemia in mice: Usefulness of adhesive removal test.

Distal occlusion of the middle cerebral artery (dMCAo), which closely mimics human stroke, is one of the most used animal models. However, although assessment of histological and functional outcome is increasingly recommended for preclinical studies, the latter is often excluded because of the high difficulties to estimate, especially in mice, behavioral impairments. The aim of our study was to deeply screen functional consequences of distal permanent MCAo in mice to target relevant behaviors for future studies. A set of sensorimotor and cognitive tests were performed during 3 weeks postsurgery in 2 groups of mice. Afterward, brain infarctions were estimated by histological staining or magnetic resonance imaging. Overall, while no long-term functional impairments could be detected, the adhesive removal was the only test showing a deficit. Interestingly, this sensorimotor impairment was correlated to cortical damage 3 weeks after surgery. In conclusion, despite the fact that dMCAo-induced deficits could not be evidenced by most of our behavioral tests, the authors showed that the adhesive removal test was the only one, sensitive enough, to highlight a long-term deficit. This result suggests therefore that this mouse model of ischemia is relevant to efficiently assess therapeutic strategies with histological but also behavioral analysis, provided that relevant tests are used. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Minnesota Multiphasic Personality Inventory correlates of lateralized cerebral lesions and aphasic deficits.

Investigated the emotional adjustment of right-handed male brain-damaged patients as a function of (a) the hemispheric location of the lesion and (b) the degree of aphasia as measured by the Halstead-Wepman Aphasia Screening Test. The Minnesota Multiphasic Personality Inventory (MMPI) profiles of 35 Ss (mean age 52.3 yrs) with right-hemisphere lesions were compared with those of 25 Ss (mean age 49.7 yrs) with left-hemisphere lesions. Both samples produced similar composite profiles that indicated the presence of mild dysphoria, dissatisfaction, withdrawal, decreased initiative, and mild somatic preoccupations. Within the left-hemisphere-damaged group, significant correlations emerged between the degree of aphasic disability and MMPI Validity, Paranoia, Psychasthenia, and Schizophrenia scales. When the variance in MMPI scores due to premorbid status (education) was partialled out, however, these correlations were nonsignificant. Findings fail to support the widely held association of speech-related deficits with psychopathology. (26 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Behavioral effects of amphetamine in rats with lesions in the corpus striatum.

Conducted 5 experiments, using a total of 132 male albino Sprague-Dawley rats. Lesions in the ventral striatum lowered forebrain dopamine and impaired avoidance behavior more severely than comparable lesions in the dorsal striatum. Ventral striatal damage also antagonized the effects of amphetamine on stereotyped behavior and on intertrial activity. Lesions in the dorsal striatum did not modify the effect of amphetamine in these tests. Neither dorsal nor ventral striatal lesions significantly depleted forebrain norepinephrine, and both failed to affect the facilitatory effects of amphetamine on exploratory activity in an open field. These observations support the hypothesis that some but not all of the behavioral effects of amphetamine may be due to the drug's action on dopaminergic components of the striatum. (32 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Behavioral treatment of Raynaud's syndrome in peripheral vascular disease.

Raynaud's syndrome is a vasospastic phenomenon that occurs in numerous peripheral vascular diseases. Because these vasospasms are sympathetically mediated, they are, according to theory, behaviorally treatable. Research has demonstrated that biofeedback, autogenic training, and progressive relaxation can all be used to treat even severe Raynaud's syndrome. However, there is no distinct advantage of one technique over the other. These techniques can be combined with sympathetic blocking agents to produce an additive effect. It is concluded that behavioral procedures have much to add to the treatment of Raynaud's syndrome. (61 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Injection of ACTH induces recovery from shuttle-box avoidance deficits in rats with amygdaloid lesions.

In an experiment with 27 female Wistar rats, amygdalectomy caused a deficit in the acquisition of a shuttle-box conditioned avoidance response and in other aversively motivated tasks, supporting previous findings. Amygdalectomized Ss given ACTH 1 hr. prior to acquisition exhibited no such deficit. Previous evidence relating the amygdaloid complex to the pituitary-adrenal axis is used as a basis for arguing that mobilization of steroid hormones is a necessary component of certain types of fear-motivated responses. (21 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Behavioral correlates of leadership effectiveness in interacting and counteracting groups.

Explored leadership within the context of 15 interacting and 15 counteracting groups with a total of 120 male introductory psychology students participating in 2 specially designed games. Results of the study indicate that while there were some leadership and followership behaviors common to both situations, situationally specific behaviors did exist. In general, results give behavioral support to F. E. Fiedler's conceptual definitions of the leadership function of interacting and counteracting groups. (30 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Failure to identify cerebral infarct mechanisms from topography of vascular territory lesions

PURPOSE: Our purpose was to determine whether topographic patterns of ischemic damage seen on brain imaging studies are useful for evaluating different mechanisms of infarction and for distinguishing embolic from hemodynamic disorders. METHODS: Early CT scans were reviewed to identify brain infarctions in the middle cerebral artery territory in 800 patients with either significant obstructive lesions of the internal carotid artery (70% stenosis, n = 17; occlusion, n = 85) or nonvalvular atrial fibrillation (n = 186) as the only identified source of stroke. Ninety-nine CT studies were considered suitable for entry into the final analysis. The scans were digitized and superimposed on postmortem brain sections by matching algorithms to display the variability of the cerebrovascular territories. RESULTS: Cortical borderzone-type infarctions were rare and evenly distributed among patients with cardiac sources of embolism (3.2%) and severe carotid obstructions (3.6%). In contrast, subcortical borderzone infarcts occurred significantly more often in patients with carotid obstructive disease (36% versus 16%). However, on computerized segmentation analysis, the topography of infarction was the same in both groups. CONCLUSION: The current concept that stroke mechanisms can be inferred from interpretation of stroke patterns on brain scans is heavily confounded by the variability in intracranial arterial territory distributions. Since individual arterial territories cannot be identified in vivo, interpretation of stroke topography is invalidated. In particular, the cortical wedge-type of borderzone infarction, said to result from hemodynamic compromise in low-flow perfusion territories, is an ambiguous observation and may be seen in patients with cerebral embolism and hemodynamic compromise due to severe carotid disease.     

Attenuation of reversal deficits of mice with septal lesions by shifts in the motivational context.

Response perseveration following septal lesions (SLs), demonstrated on tasks that require change of a learned pattern of responding, depends in part on a relatively constant motivational context. The present experiment examined the effects of concurrent changes in the temperature of the water in a water-escape maze and the reversal of a spatial discrimination in 83 male Binghamton heterogeneous mice that had received either SLs or control surgery. Control and experimental Ss were trained on a spatial discrimination in either 17 or 34°C water. Following acquisition, reversal training was conducted in the maze filled with the same temperature water used during acquisition, or both water temperature and spatial reinforcement contingencies were reversed. When the water temperature remained constant across acquisition and reversal, Ss with SLs showed persistence during reversal training. Changing the water temperature concurrently with the institution of reversal training attenuated the perseverative deficits of Ss with SLs, in contrast to the relative lack of effect in controls. The role of the septal region in attention is discussed. (28 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Septal lesions in rats produce reversal deficits in a simultaneous visual discrimination.

Trained 54 rats with septal lesions and their operated controls on a 2-choice simultaneous brightness discrimination problem and its reversal using a correction procedure in a maze with 4 sequential choice points. Rats with septal lesions were deficient in the reversal of this brightness discrimination. However, this deficit was seen only in a measure of repeated errors and was considerably altered by forced preexposure to selected cues involved in discrimination. Thus, perseveration was seen, as measured by repeated errors, even though rats with lesions reached criterion in the same number of trials as operated controls. Findings emphasize the critical nature of stimulus conditions, response measures, and the history of the animal in determining the effects of brain damage on behavior. (37 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Comparative learning and memory deficits following hippocampal and caudate lesions in mice.

Examined the effects of hippocampal, caudate, combined hippocampal-caudate, and sham lesions on the passive avoidance and active escape performances of groups of female CF1 mice. Bilateral hippocampal or caudate lesions produced similar impairments of passive-avoidance retention 1 day after training in Ss operated upon 1 day prior to training. Hippocampal and caudate lesions similarly facilitated active-escape retention. When surgery was performed immediately after training, hippocampal or caudate lesions each impaired both passive-avoidance and active-escape retention 1 day later; no retention deficits were observed when surgery was performed 1 hr. after training. When surgery was performed immediately after training and passive-avoidance retest was conducted 1 hr. later, only hippocampal lesions impaired retention. These and other data suggest the mediation of different neuroanatomical substrates for short- and long-term memory and different processes for storage and forgetting. (19 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Dissociation of spatial discrimination deficits following frontal and parietal lesions in monkeys.

Gave 40 rhesus monkeys dorsolateral prefrontal, posterior parietal, or inferotemporal lesions. 4 additional Ss served as unoperated controls. Ss then received 2 forms of spatial discrimination training, based on body position ("egocentric" cues) and on the position of an external referent ("allocentric" cues), respectively. On the former, a place discrimination reversal, frontal Ss were impaired but not parietals. On the latter, a landmark discrimination reversal, parietal Ss were impaired but not frontals; this result was also obtained on a test involving distance discrimination without reversal. Finally, the inferotemporals but not the frontals or parietals were impaired on a nonspatial object discrimination reversal. Results suggest that the 2 modes of spatial orientation, egocentric and allocentric, are related to frontal and parietal mechanisms, respectively. (18 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Asymmetrical effects of unilateral cortical suction lesions: Behavioral characterization.

Assessed behavioral effects of unilateral frontocortical suction lesions in the right and left hemispheres in 24 male Sprague-Dawley rats, using a computerized activity monitoring system. Lesions of the right frontal cortex produced postoperative hyperactivity consisting of increases in the total distance traveled, average distance per movement, and average speed of movement. Vertical, rotational, and stereotypic measures were not changed. Ss receiving left hemisphere lesions did not differ from sham-operated controls on any behavioral variable. The lateralized hyperactivity resulting from lesions of the right frontal cortex was confined to increased length and speed of horizontal movement and did not appear to represent a generalized increase in all components of spontaneous activity. (10 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Critical determinants of nonspatial working memory deficits in rats with conventional lesions of the hippocampus or fornix.

Rats with conventional lesions of the hippocampus or fornix were compared postoperatively with controls on nonspatial memory tasks. Neither lesion impaired delayed matching-to-sample (DMS) performance in a discrete-trial task involving "pseudo-trial-unique" complex stimuli. An impairment emerged if a single pair of complex stimuli was used throughout each day's session, and the greatest impairment was obtained with the use of a single pair of less complex stimuli throughout each day's test. Transfer to continuous DMS task with no explicit intertrial interval produced a different pattern because both lesion and control levels of performance were depressed when 2 complex stimuli were used repeatedly. A final, separate discrimination learning experiment showed that hippocampectomized rats readily discriminated between the stimuli associated with the greatest lesion-induced DMS deficit. Hippocampal dysfunction thus produces clear deficits on nonspatial memory tasks under appropriate test conditions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Correlating MR lesions and functional deficits in multiple sclerosis patients. Anatomical atlas registration

Although brain magnetic resonance (MR) imaging is increasingly being used as an objective outcome measure in treatment trials for multiple sclerosis (MS), findings correlating conventional MR imaging and disabilities in established MS have been inconsistent. In some studies, measures of MR lesion status, such as numbers of lesions or MS lesion load (volume), have shown limited correlations with clinical scores such as the Kurtzke Expanded disability scale (EDSS). Other studies have shown clear correlations between MR findings and measures of disability in MS. Further development of image processing techniques should help elucidate the relationships between MR findings and disease processes in MS.     

Acute prognosis and differentiation of various cerebral infarct groups in comparison with cerebral hemorrhage

For clinical trials classification of stroke should be possible at the bedside by simple methods that are available every where. In this study are 1105 patients with every first ischaemic strokes and 130 patients with intracerebral haemorrhages. The differences between severity of clinical symptoms, outcome and risk factors of intracerebral haemorrhages, ischaemic stroke caused by cerebral microangiopathy, ischaemic stroke combined with extracranial carotid stenosis, cardiogenic brain embolism and atherothrombotic stroke, were analysed. Intracerebral haemorrhages show the poorest outcome of all groups (mortality 23.8%), due to increased intracranial pressure. Cardiogenic brain embolism is more frequent in older women (mean age 77.8 y.). Main risk factor is atrial fibrillation with absolute arrhythmia. The outcome of this group is the worst of all subgroups of ischaemic stroke and survivors most often in need of institutionalization. Patients with ischaemic stroke combined with extracranial carotid stenosis are significantly younger (mean age 67.6 y.), predominantly male, and smokers. Their mortality is low (0.63%), but recovery of paresis is slower than in other subgroups. Ischaemic strokes caused by cerebral microangiopathy with hypertension as main risk factor recover most quickly but acute mortality is higher than in ischaemic stroke combined with extracranial carotid stenosis because of higher age (mean age 74.5 y.). Institutionalization is more frequent too because of higher incidence of dementia in this subgroup. The main prognostic factors of all groups are age and severity of clinical symptoms. A special subgroup are infratentorial ischaemic strokes.(ABSTRACT TRUNCATED AT 250 WORDS)     

Activation PET scanning in pretreatment evaluation of patients with cerebral tumours or vascular lesions in or close to the sensorimotor cortex

Calmodulin is a ubiquitous transducer of calcium signals in eukaryotes. In diploid plant species, several isoforms of calmodulin have been described. Here, we report on the isolation and characterization of calmodulin cDNAs corresponding to 10 genes from hexaploid (bread) wheat (Triticum aestivum). These genes encode three distinct calmodulin isoforms; one isoform is novel in that it lacks a conserved calcium binding site. Based on their nucleotide sequences, the 10 cDNAs were classified into four subfamilies. Using subfamily-specific DNA probes, calmodulin genes were identified and the chromosomal location of each subfamily was determined by Southern analysis of selected aneuploid lines. The data suggest that hexaploid wheat possesses at least 13 calmodulin-related genes. Subfamilies 1 and 2 were both localized to the short arms of homoeologous-group 3 chromosomes; subfamily 2 is located on all three homoeologous short arms (3AS, 3BS and 3DS), whereas subfamily 1 is located only on 3AS and 3BS but not on 3DS. Further analysis revealed that Aegilops tauschii, the presumed diploid donor of the D-genome of hexaploid wheat, lacks a subfamily-1 calmodulin gene homologue, whereas diploid species related to the progenitors of the A and B genomes do contain such genes. Subfamily 3 was localized to the short arm of homoeologous chromosomes 2A, 2B and 2D, and subfamily 4 was mapped to the proximal regions of 4AS, 4BL and 4DL. These findings suggest that the calmodulin genes within each subfamily in hexaploid wheat represent homoeoallelic loci. Furthermore, they also suggest that calmodulin genes diversified into subfamilies before speciation of Triticum and Aegilops diploid species.     

Chronic motion perception deficits from midline cerebellar lesions in human

A selective motion perception deficit is seen in patients with acute midline cerebellar lesions. Patients with more lateralized acute cerebellar damage do not demonstrate such a deficit (Nawrot M, Rizzo M. Vis Res 1995;35:723-731). However, as these patients were tested only between 10 and 14 days post-ictus, the stability of this perceptual deficit into the chronic phase remained undetermined. The current study extends the previous findings by showing that the motion perception deficit caused by mid-line cerebellar lesions remains permanent at least 2 years into the chronic phase. The extent and longevity of this deficit resembles that of the well known motion-blind patient LM who has a large cerebellar lesion in addition to her extensive cortical damage. Again, we propose that the mid-line cerebellar damage may produce a severe motion perception deficit by disruption the visual-motor integration mechanisms involved in perceptual stabilization, even though cortical motion processing mechanisms are unaffected.     

Some observations on the preference deficits produced by lateral preoptic lesions in the rat.

Conducted 4 experiments with a total of 20 female albino Sherman rats which show that, following water deprivation, Ss with lateral preoptic (LPO) damage lost the normal preference for glucose solutions. Food deprivation reinstated the preference. This dependency was specific to sweet-tasting fluids, and the deficit persisted even when thirst was alleviated prior to the preference test. Such Ss would drink sweet solutions in response to intravascular fluid depletion, but they were deficient in response to sweet solutions under nondeprived conditions. This last finding in particular suggests that hunger and palatibility, as determinants of the response to sweet solutions, may be dissociated by LPO damage. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)