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D P Alfano

Publications and source records attributed to D P Alfano.

15 recordsLinked to original sources
PubMed2006

Neuropsychological correlates of impaired emotion recognition following traumatic brain injury.

Previous research has shown that individuals with traumatic brain injury (TBI) are significantly impaired on emotion recognition tasks. In this study, the relationship between neuropsychological functioning and emotion recognition was examined in 11 individuals with moderate to severe TBI and a control group of 13 individuals matched for age,sex, and education. Emotion recognition stimuli were from Ekman and Friesen's pictures of facial affect. The group with TBI showed neuropsychological deficits consistent with those commonly found following moderate to severe TBI. The group with TBI also identified significantly fewer emotion recognition stimuli than the control group. The number of correctly identified emotion recognition stimuli was significantly correlated with measures of verbal cognitive processing in the group with TBI. These findings suggest that the role of left hemisphere brain mechanisms in the recognition of facial (nonverbal)emotion may be more important than previously recognized.

Adult↗
PubMed2006

Emotional and pain-related factors in neuropsychological assessment following mild traumatic brain injury.

A critical issue in the field of clinical neuropsychology is the idea that emotional or pain-related factors may compromise the validity of neuropsychological assessment. In this study, 53 individuals suffering from mild traumatic brain injury related to motor vehicle accident injury completed commonly used measures of emotional and pain-related functioning. A battery of commonly used neuropsychological tests, assessing attention, learning and memory, language, visuospatial and visuomotor functions, speeded processing, fine-motor skill, and symptom validity, was administered concurrently. Findings revealed a significant and negative correlation between anxiety and impaired delayed verbal memory, suggesting that as anxiety increased, delayed verbal memory decreased. The results otherwise provided little support for the idea that emotional or pain-related factors are detrimental to neuropsychological test performance following mild traumatic brain injury.

Accidents, Traffic↗
PubMed2005

The symptom checklist-90-revised and mild traumatic brain injury.

OBJECTIVE: Assessment of emotional functioning is a critical aspect of the clinical neuropsychological evaluation of individuals following mild traumatic brain injury (MTBI). The objective of this study was to examine the utility of the Symptom Checklist-90-Revised as a brief tool for assessing psychological and symptomatic distress following MTBI. METHOD: A contrasted groups approach, involving three clinical groups (MTBI, Whiplash Associated Disorder, Type I Diabetes) and a non-clinical control group, was used in this study. RESULTS: The group with MTBI scored significantly higher on the majority of primary symptom dimensions and global distress indices of the SCL-90-R compared to both the diabetes and non-clinical control groups. Analysis of individual cases further revealed that 68.2% of the participants in the group with MTBI were classified as positive cases, a rate significantly higher than that of the diabetes and non-clinical control groups. The group with MTBI did not differ significantly from the group of individuals with whiplash associated disorder with respect to elevation of primary symptom dimensions or global distress indices, or the number of cases classified as positive. CONCLUSION: The results of this study suggest that the SCL-90-R has considerable utility as a general measure of psychological and symptomatic distress following MTBI.

Adult↗
PubMed1995

Dimensions of neurobehavioural dysfunction: cross-validation using a head-injured sample.

Principal-components analysis of 44 items from the Minnesota Multiphasic Personality Inventory (MMPI) identified as neurologically related was conducted on profiles obtained from 196 individuals with head injury. Four principal factors, that accounted for 36.5% of the total variance, were extracted. The first factor was composed of items tapping attention and memory complaints. The second factor consisted of items focusing on somatic complaints. Items primarily tapping behavioural disturbance made up the third factor, and the fourth factor was composed of items reflecting specific somatic or neurological complaints. These findings partially confirmed those obtained in previous research, and further illuminate the need for developing a specific and brief measure to characterize neurobehavioural dysfunction for neurological samples.

Adolescent↗
PubMed1994

Social support, locus of control and psychological health in family members following head or spinal cord injury.

Perceived stress and psychological health were comparatively examined in relation to social support and locus of control in family members of patients who had sustained moderate to severe closed head injury (CHI) or spinal cord injury (SCI). In the group with CHI, family members reported significantly greater symptoms of depression, and greater perceived stress in relation to difficult personality characteristics of the patient and day-to-day problems involved in caregiving. The family members of the patients with SCI reported significantly greater social support within the family. In the group with CHI, an internal locus of control and greater social support from friends, but not other family members, were significantly correlated with lower levels of perceived stress and better psychological health. In the group with SCI, greater social support from both family and friends was significantly correlated with lower levels of perceived stress and better psychological health. The results of this study are consistent with the notion that social support and locus of control may significantly, albeit differentially, moderate the effects of profound life changes in these groups. The implications of these findings are discussed in terms of intervention strategies that may be utilized to facilitate family adjustment following CHI or SCI.

Journal Article↗
PubMed1994

Sources of stress in family members following head or spinal cord injury.

Sources of stress and perceptions of patients' psychosocial adjustment were comparatively examined in the family members of patients who had sustained moderate to severe closed head injury (CHI) or spinal cord injury (SCI). The family members of the patients with CHI reported significantly greater stress in relation to lack of social support, overcommitment, and difficult personality characteristics of the patient. Physical incapacitation of the patient was the principal source of stress that significantly differentiated the family members of the patients with SCI. Family members' perceptions of patients' psychosocial adjustment, as assessed across a broad range of dimensions that included the domestic and social environments, did not differ significantly between the groups. In both groups, the level of personal psychological distress reported by the family members was the most significant and consistent correlate of their perceived stress and perceptions of patients' psychosocial adjustment. The results are discussed In terms of the need to expand the traditional scope of rehabilitative efforts following head and spinal cord injury to directly address family-related issues.

Journal Article↗
PubMed1986

Halstead's Category Test: withstanding the test of time.

In spite of demonstrated validity, Halstead's Category Test has been criticized as overly time consuming. In order to evaluate this assumption, groups of severely head-injured and general neurological cases were administered the Category Test as part of routine evaluation, and the time to completion of the test was recorded. The results indicated that 93% of the patients completed the test in less than 1 h and that 50% completed it in less than 40 min. In 81% of the cases, the test lasted from 20-50 min.

Adolescent↗
PubMed1985

Postnatal lead exposure and the cholinergic system.

Previous reports have suggested that the behavioral effects of early lead (Pb) exposure may be due to an underlying deficiency in cholinergic function. To further examine this possibility, Long-Evans hooded rat pups were exposed to Pb for the first 25 postnatal days via the maternal milk. Dams were fed either 4.0% PbCO3 (High Pb), 0.4% PbCO3 (low Pb) or a Na2CO3 control diet throughout this period. Beginning at 65 days of age, animals were tested on behavioral tasks sensitive to both Pb exposure and cholinergic deficiency. Exposure to both levels of Pb impaired passive avoidance acquisition and produced lower rates of spontaneous alternation. Pb, however, had no clear effects on open field activity. The cholinergic agonist physostigmine (0.05 and 0.075 mg/kg) did not affect the behavior of control animals on any task, but in both Pb exposed groups physostigmine improved passive avoidance acquisition, increased the rate of spontaneous alternation and lowered open field activity scores. The cholinergic antagonist scopolamine (0.4 mg/kg) impaired passive avoidance acquisition, lowered the rate of spontaneous alternation and increased open field activity scores in control animals. Consistent with behavior characteristic of an inverted U shaped response curve, scopolamine (0.2 and 0.4 mg/kg) improved passive avoidance acquisition in both Pb exposed groups and decreased open field activity scores in the High Pb group. In all cases, the behavioral response of the Pb exposed animals may be interpreted as responses characteristic of cholinergically deficient animals. These results thus provide further evidence for cholinergic system involvement in the behavioral changes observed following early exposure to Pb.

Animals↗
PubMed1984

Synaptic development in the human fetus: a morphometric analysis of normal and Down's syndrome neocortex.

Postmortem tissue was obtained from six normal and four Down's syndrome brains ranging in age from 12 to 40 weeks postconception. Tissue was processed for electron microscopy using routine osmium and EPTA staining procedures, and to examine synaptic development, photomicrographs were systematically taken throughout the molecular layer of the sensorimotor neocortex. The number of EPTA-stained synapses were consistently greater than the number of osmium-stained synaptic contacts. A progressive increase in synaptic density throughout the range of ages examined was observed for both normal and Down's syndrome tissue. There was also an increase with developmental age in apparent measures of synaptic maturity, e.g., an increased ratio of mature to primitive contacts and asymmetrical to symmetrical contacts. In normal tissue, pre- and postsynaptic membrane lengths were observed to increase with the ages studied, whereas synaptic membrane widths appeared to attain mature values by 29 weeks postconception. Cleft width remained fairly constant to 28 weeks postconception. Although direct statistical comparisons could not be made, in Down's tissue synaptic parameter development was generally less consistent and the parameters appeared to be reduced during the later stages of development studied.

Down Syndrome↗
PubMed1983

Development and plasticity of the hippocampal-cholinergic system in normal and early lead exposed rats.

A review of previous evidence suggested the possibility of a functional association between the effects of early lead (Pb) exposure, hippocampal damage and cholinergic deficiency. To further assess this possibility, Long-Evans hooded rat pups were exposed to Pb for the first 25 postnatal days via the maternal milk. Dams were fed either 4.0% PbCO3 or a Na2CO3 control diet throughout this period. At 30 and 115 days of age, the brains of Pb and control animals were processed for acetylcholinesterase histochemistry. Morphometric evaluation of the molecular layer of the hippocampal dentate gyrus indicated that while absolute increases in the dimensions of the afferent systems to the hippocampal dentate gyrus are observed between 30 and 115 days of age, no significant rearrangement in the pattern of lamination occurs during this time. No effects of Pb were seen on the development of the cholinergic innervation of this brain region at either of these ages. Unilateral perforant path transections performed on Pb and control animals at 100 days of age indicated reduced cholinergic plasticity in the molecular layer of the hippocampal dentate gyrus of Pb exposed animals, as indicated by AChE histochemistry. These findings indicate that a decrease in neuroanatomical plasticity may be a critical brain mechanism underlying the learning deficits observed following exposure to Pb.

Acetylcholinesterase↗
PubMed1983

Early lead exposure and the hippocampus: a review and recent advances.

A review of previous evidence suggests an association between early Pb exposure and hippocampal dysfunction. This report summarizes recent experiments conducted in both our laboratory and others' examining the effects of early Pb exposure on hippocampal morphological development, and behaviors characteristic of hippocampal dysfunction. Following postnatal Pb exposure marked reductions are seen in general hippocampal development and in the axonal and dendritic development of hippocampal dentate granule cells. Correlated with these neuroanatomical changes are Pb induced behavioral changes which show numerous similarities to those behavioral changes seen following damage to both the adult and developing hippocampus. These observations thus support the suggestion that the hippocampus may play a critical role in mediating many of the behavioral changes observed following early Pb exposure, as well as indicate that the hippocampus may serve as an excellent model system for further examining the neurobehavioral effects of Pb. However, as other brain areas are also clearly effected by Pb, alternative explanations for these lead induced behavioral changes are also discussed.

Acoustic Stimulation↗
PubMed1979

Differential experience following developmental lead exposure: effects on brain and behavior.

Long Evans hooded rat pups were exposed to lead (Pb) via the maternal milk supply from Postnatal Day 1 (PN 1) to PN 25. Mothers were fed diets containing either 4% Pb CO3 (High Pb), 0.4% Pb CO3 (Low Pb) or 2.2% Na2 CO3 (Controls) throughout this period. Pups were weaned at PN 30 and littermates randomly assigned to either an Enriched or Isolated environment for a period of 30 days. Increases in activity levels and decreases in passive avoidance latencies were observed in Pb exposed animals. However, there were minimal effects due to Pb on symmetrical maze performance. Experience in the enriched environment had no effect on open field activity levels but resulted in a marked reduction in symmetrical maze errors. While enrichment had no effect on passive avoidance performance in High Pb animals, it was capable of raising latencies in Low Pb animals to Control values. Thus, the therapeutic value of environmental enrichment in Pb exposed animals depends on both the task employed and the severity of the pre-enrichment brain damage. From both brain regional analysis and behavioral testing results, it appeared that the hippocampus was a major site of Pb action. From comparison of blood Pb levels of our animals and those reported in children, it became apparent that the rat may have a greater tolerance for Pb, and as such, caution must be used in making direct comparisons between the two species in terms of blood Pb levels.

Animals↗