PubMed Health⌕ Search

Biomedical subjects

S Finger

Publications and source records attributed to S Finger.

At least 55 records · Page 3Linked to original sources
PubMed1987

Effects of medial frontal cortex lesions on DRL performance in rats.

Rats with medial frontal cortical lesions (MFC) and control animals with sham operations were tested on an ascending series of 8 DRL schedules of reinforcement ranging from 5 to 70 seconds. Rats with MFC lesions did not differ from the control group in performance when response rate, responses per reinforcement and efficiency were analyzed. These results indicate that deficits in "response inhibition" often displayed by rats with MFC lesions may be task-specific.

Animals↗
PubMed1987

Large and small medial frontal cortex lesions and spatial performance of the rat.

Rats with sham operations, or small or large medial frontal cortex lesions were compared for the acquisition of a position habit and for learning a series of 4 position habit reversals. No differences were found during acquisition of the position habit. On the reversals, the rats with the larger lesions were markedly impaired, while less severe deficits or control-like performance characterized the rats with the smaller ablations. Analyses of the error scores showed that the rats with the larger lesions made more perseverative errors than the other groups and performed more sporadically even after breaking a previous position habit. These results confirm the hypothesis that a strong relationship exists between medial frontal cortex lesion features (depth and length) and performance. The differences found in acquisition vs. reversal learning, and the nature of the errors observed, also suggest that this part of the brain functions as more than simply a spatial analyzer.

Animals↗
PubMed1987

The family support group in the treatment of amyotrophic lateral sclerosis.

Support groups are effective means of addressing the psychosocial needs of patients with amyotrophic lateral sclerosis and their families. An education-support group for family members of patients with ALS has been functioning at New England Medical Center in Boston and has been found to be successful in helping families and, therefore, patients to cope with this stressful illness. This article discusses the benefits of this group to families and patients, family members' roles in caring for and coping with this illness, the group's structure and development, and gives suggestions to others who are considering running a group of this kind. Our experience has shown that group participants feel less isolated, less fearful, and less threatened than prior to their involvement in the group and gain a sense of empowerment that enables them to meet the extensive caretaking demands of the patient with ALS. The contribution that an ALS Family Support Group provides is a component in the care of the patient with ALS that can be critical to families dealing with this illness.

Amyotrophic Lateral Sclerosis↗
PubMed1986

Behavioral effects of large and small lesions of the rat medial frontal cortex.

Rats with either sham operations, small medial frontal cortex lesions (SMF), or large medial frontal cortex lesions (LMF) were tested in the open field, for spatial alternation and for 8-arm maze learning. The behaviors of sham-operated and SMF rats were similar on the spatial learning tasks, while the LMF group performed poorly in relation to these two groups. In contrast, the two lesion groups differed from the sham group, but not from each other, on locomotor activity in the open field. The differences in performance between the SMF and LMF groups on the spatial learning measures suggest that medial frontal cortex lesion size and locus may be important factors underlying the variable results of previous studies evaluating spatially-oriented behaviors of rats with varying degrees of medial frontal cortex damage.

Animals↗
PubMed1986

Behavioral effects of severe and moderate early malnutrition.

Rats with a history of prenatal and early postnatal undernutrition (6 or 8% casein diets) were "nutritionally rehabilitated" at weaning, and were compared to well-fed animals (25% casein) at maturity. The severely-malnourished (6%) animals were hyperactive in the open field and when tested in a stabilimeter. They also appeared to be highly active during the early trials in 8-arm radial maze testing where they made more arm entries and re-entry errors than the well-fed rats. In terms of trials to criterion, however, their scores on the radial maze and on a spatial alternation task fell within normal limits. The moderately-malnourished (8%) rats tended to perform at control levels on the learning measures, but these rats were not as active as the 6% rats on the measures of activity. Brain size and weight differences among the three groups of rats also are presented and discussed.

Animals↗
PubMed1986

Severe early malnutrition and DRL performance in the rat.

Rats with a history of severe early malnutrition (6% casein) were compared to well-fed control animals on an ascending series of DRL values ranging from 5 to 60 seconds. The 6% rats who were dietarily-rehabilitated at weaning did not differ from control animals in efficiency, responses per reinforcement or response rate. In contrast, rats chronically exposed to 6% diets performed so poorly during training with continuous reinforcement that they did not advance to even the first DRL (5-sec) condition. These findings show that severely-undernourished rats can perform within normal limits on even high DRL values, provided they are well trained and that they have adequate nutritional rehabilitation.

Animals↗
PubMed1985

Brain damage and neuroplasticity: mechanisms of recovery or development?

Brain damage may be followed by a number of dynamic events including reactive synaptogenesis, rerouting of axons to unusual locations and altered axon retraction processes. In the present theoretical review, the relationship between these morphological changes and behavioral recovery of function is examined from two perspectives. First, an examination of the research literature reveals that the association between these reorganizational events and recovery of function is inconsistent, and it is proposed that in most cases a causal relationship between neural reorganization and behavioral recovery remains speculative at best. It is further noted that aberrant neural circuitry has been associated with neurological dysfunction in many studies. Second, evolutionary considerations suggest that there is little reason to believe that neural reorganizational events emerged to 'heal' damaged brains. Both experimental and evolutionary orientations support the idea that neuronal circuitry changes in response to injury can be better understood as developmental growth processes that are triggered or potentiated in response to cell loss, rather than as recovery or healing processes. The contribution of 'growth' to behavioral recovery of function may be inconsistent because these growth processes are occurring against the backdrop of a damaged brain and may make connections different from those ordinarily seen. Further, they must be considered in conjunction with phenomena such as diaschisis and compensation which may also influence behavioral changes following neural injury.

Acute Disease↗
PubMed1984

Effects of age, brain damage and stress on antibody binding to the brain.

The direct immunoperoxidase technique was used to assess IgG and IgM nuclear and cytoplasmic binding to the mouse brain as a function of age, brain damage, and stress. Nuclear IgM binding was found to increase in older animals (over 30 months of age). There was also heightened nuclear and cytoplasmic binding 1 week after a frontal cortex lesion in mice approximately 2 months of age. Mice with brain lesions, however, did not show greater binding some months later and, if allowed to die from natural causes, actually showed less IgM nuclear binding than control animals. No association was found between lifespan and binding or between stress per se and binding. The capacity of the blood-brain barrier to repair itself after injury is discussed, and these findings are compared to earlier data based on indirect measurement procedures.

Age Factors↗
PubMed1982

Swimming as a method for assessing motor cortex integrity in the rat.

Rats were tested on 6 measures of swimming behavior 1, 2 and 4 weeks after sham operations or bilateral motor cortex lesions that damaged the forelimb areas and axons controlling the axial musculature. Rats with lesions performed more forelimb kicks and showed larger body angles than control animals. Number of hindlimb kicks and speed were within normal limits. Thus, some measures of swimming can be affected by small motor cortex lesions that spare the hindlimb projections.

Animals↗
PubMed1982

Behavioral effects of early deprivation of nerve growth factor: some similarities with familial dysautonomia.

Female rats immunized with mouse nerve growth factor develop an antibody (anti-NGF) which reaches offspring through the placenta and via the milk. Pups exposed to maternal anti-NGF have fewer dorsal root and sympathetic neurons. When the offspring are examined on a wide variety of behavioral tests, they exhibit severe deficits in response to stress (ulceration, corticosterone levels), and mild deficits on some sensory and cognitive tasks. Exploratory and motor functions, however, are relatively normal. The pathologic and behavioral profiles of the animals closely mimic the sensory and sympathetic aspects of familial dysautonomia.

Animals↗
PubMed1982

Recovery time and sensorimotor cortex lesion effects.

Rats received one-stage, bilateral lesions of the individual sensorimotor cortex areas (Sm-1, Sm-2) and were compared to sham operated rats or rats with lesions of Sm1 + 2 in learning a series of 5 ridge-smooth tactile discriminations. Some rats began testing 1 or 2 weeks after surgery, while others remained in their home cages for 1 month, 6 months, 1 year or 2 years before beginning testing. The rats with combined Sm1 + 2 lesions performed very poorly regardless of recovery time, and those with sham operations performed extremely well even when tested late in life. The animals with either Sm-1 or Sm-2 lesions did not do well after the shorter recovery periods, but obtained scores within the sham operated group range when given 1 year. (Sm-2) or 2 years (Sm-1) for recovery. These data show that spared parts of the damaged system are important in mediating tactile discriminative behavior. However, the reasons for the long delays in recovery are not clear.

Animals↗
PubMed1982

Brain damage, stress, and life span: an experimental study.

Mice received frontal pole transections or sham operations, and approximately half in each group experienced cold stress five times throughout their lives. On two occasions certain selected animals were subjected to cold + restraint stress. Neither the brain lesions nor the cold stress affected life span. The stressors, however, were effective in temporarily elevating serum corticosterone levels and, in the case of cold + restraint, producing gastric stress erosions. A significant partial correlation between stress and cause of death was found. This effect appeared to be due primarily to reticulum cell sarcomas metastasizing to the lung (pulmonary tumors) with much greater frequency among animals exposed to stress.

Animals↗
PubMed1981

Undernutrition and recovery from brain damage: a preliminary investigation.

Rats undernourished early in life did not differ from control animals in acquiring a light-dark discrimination. Posterior cortical lesions impaired retention in both nutritional groups, but the relearning scores of the undernourished animals with lesions were significantly worse than those of the lesion group that had been well fed. Amphetamine was found to enhance recovery, especially in the undernourished group. These data thus show that early nutritional history can be an important factor in accounting for differences in performance following later, focal brain damage, but that pharmacological intervention still can be of great value in these cases.

Animals↗
PubMed1981

Effects of one- and two-stage lesions of the posterior hypothalamus on temperature regulation in the rat.

Rats received 1-stage bilateral and sequential unilateral (serial) lesions of the posterior hypothalamus and were tested for the ability to regulate body temperature after a lengthy recovery period. The groups with lesion differed from the sham-operated groups in the cold, although not under ambient or warm conditions. The fact that the serial lesion group performed the same as the 1-stage lesion groups in the cold is significant because earlier tests on these same animals revealed much better recovery after serial lesions in swimming, and a partial serial lesion effect in open field performance.

Animals↗