Presurgical assessment of memory-related brain structures: the Wada test and functional neuroimaging

Medial temporal lobe structures are known to play a major role in memory processing. Recent work has revealed that extratemporal structures (e.g. the frontal lobe and thalamus) may also be important in memory function. In candidates for epilepsy surgery, particularly in those with temporal lobe seizures, presurgical evaluation of memory function is essential, since seizures may originate in the neural substrate that is critical for memory. In this article, we review the tools used for presurgical evaluation and their contribution to the understanding of memory function, focusing on the Wada test, [18F]fluorodeoxy-glucose positron emission tomography ([18F]FDG-PET) and functional magnetic resonance imaging (fMRI). We also explore perspectives on future studies that may elucidate the role of the temporal and extratemporal structures in memory function and the mechanisms of cerebral plasticity.

Playing ice hockey and basketball increases serum levels of S-100B in elite players: a pilot study

OBJECTIVE

To investigate changes in serum concentrations of the biochemical markers of brain damage S-100B and neuron-specific enolase (NSE) in ice hockey and basketball players during games.

DESIGN

Descriptive clinical research.

SETTING

Competitive games of the Swedish Elite Ice Hockey League and the Swedish Elite Basketball League.

PARTICIPANTS

Twenty-six male ice hockey players (from two teams) and 18 basketball players (from two teams).

INTERVENTIONS

None.

MAIN OUTCOME MEASURES

S-100B and NSE were analyzed using two-site immunoluminometric assays. The numbers of acceleration/deceleration events were assessed from videotape recordings of the games. Head trauma-related symptoms were monitored 24 hours after the game using the Rivermead Post Concussion Symptoms Questionnaire.

RESULTS

Changes in serum concentrations of S-100B (postgame - pregame values) were statistically significant after both games (ice hockey, 0.072 +/- 0.108 microg/L, P = 0.00004; basketball, 0.076 +/- 0.091 microg/L, P = 0.001). In basketball, there was a significant correlation between the change in S-100B (postgame-pregame values) and jumps, which were the most frequent acceleration/deceleration (r = 0.706, P = 0.002). For NSE, no statistically significant change in serum concentration was found in either game. For one ice hockey player who experienced concussion during play, S-100B was increased more than for the other players.

CONCLUSIONS

S-100B was released into the blood of the players as a consequence of game-related activities and events. Analysis of the biochemical brain damage markers (in particular S-100B) seems to have the potential to become a valuable additional tool for assessment of the degree of brain tissue damage in sport-related head trauma and probably for decision making about returning to play.

Cognitive rehabilitation in schizophrenia: a quantitative analysis of controlled studies

RATIONALE

Cognitive rehabilitation is now recognized as an important tool in the treatment of schizophrenia, and findings in this area are emerging rapidly. There is a need for a systematic review of the effects of the different training programs.

OBJECTIVES

To review quantitatively the controlled studies on cognitive rehabilitation in schizophrenia for the effect of training on performance on tasks other than those practiced in the training procedure.

METHODS

A meta-analysis was conducted on 12 controlled studies of cognitive rehabilitation in schizophrenia taking into account the effects of type of rehabilitation approach (rehearsal or strategy learning) and duration of training.

RESULTS

The mean weighted effect size was 0.45, with a 95% confidence interval from 0.26 to 0.64. Effect sizes differed slightly, depending on rehabilitation approach, in favor of strategy learning, but this difference did not reach statistical significance. Duration of training did not influence effect size.

CONCLUSIONS

Cognitive rehabilitation can improve task performance in patients with schizophrenia and this effect is apparent on tasks outside those practiced during the training procedure. Future studies should include more real-world outcomes and perform longitudinal evaluations.

Minimal model to document psychometric change after standard anterior temporal lobectomy for intractable seizure disorder

Neuropsychological assessment of persons with epilepsy is recommended whenever neurosurgery is considered as an alternative therapy for seizure disorders refractory to ordinary medical management. Although psychological assessment is common in centers specialized in the care of epilepsy patients, standardized protocols are not common. This study addresses the question of the optimal minimal test battery necessary to differentiate groups of right-handed patients with refractory, complex partial seizure disorder who receive either right or left anterior temporal lobectomy or no surgery. No variable differentiated the groups before surgery. Only Logical Memory-Immediate of the Wechsler Memory Scale differentiated the groups following surgery. This finding is consistent with the literature.

The Effects of Intensive Voice Treatment on Facial Expressiveness in Parkinson Disease

OBJECTIVE

The purpose of the present retrospective study was to examine the effects of intensive voice therapy on facial expression in Parkinson disease.

BACKGROUND

Parkinson disease (PD) often presents with symptoms that reduce communicative effectiveness on multiple levels, including decreased vocal loudness and reduced facial mobility. Recent advances in voice treatment have provided the first short- and long-term efficacy data indicating improvements in voice and speech following intensive voice therapy (Lee Silverman Voice Treatment [LSVT]). Anecdotal reports from both clinicians and patients indicate that the LSVT also has a positive impact on facial expression. These observations suggest a need to investigate more directly the effects of voice therapy on facial movement and expressiveness in PD.

METHOD

Forty-four individuals with idiopathic PD participated in this study. Video data were taken from recordings of individuals with PD who had received either one month of phonation-based treatment (LSVT) or respiratory treatment (RT) as part of a large treatment efficacy study designed to examine the effects of different types of therapy on speech and voice in PD. Twenty-second video samples of all subjects taken before and after treatment were paired and played at random without sound to trained raters, who judged each pair of video clips for facial mobility and engagement. All recordings were made while subjects were engaged in conversational speech.

RESULTS

Inter-rater reliability was extremely high (0.90) for both the rating of facial mobility and engagement. Overall, members of the LSVT group received more ratings of increased facial mobility (P = 0.036) and engagement (P = 0.056) following treatment relative to members of the RT group. In addition, the extent of change for facial mobility after treatment was perceived as greater (P = 0.05) for the LSVT group than for the RT group.

CONCLUSIONS

These results indicate that intensive voice therapy may have a positive effect on facial expressivity in PD. Such findings lend support to contemporary theories relating multiple expressive modalities (e.g., voice, face, and gesture) and suggest that targeting voice may be an effective and efficient way to influence expressive output in general.

Impact of viral and bacterial burden on cognitive impairment in elderly persons with cardiovascular diseases

BACKGROUND AND PURPOSE

Inflammation and infectious etiology have been implicated in the pathogenesis of dementia. We sought to investigate whether the seropositivity of common infections was associated with cognitive function.

METHODS

Viral burden (seropositivity for herpes simplex virus type 1 [HSV-1], herpes simplex virus type 2 [HSV-2], or cytomegalovirus [CMV]) and bacterial burden (Chlamydia pneumoniae and Mycoplasma pneumoniae) were related to cognitive status and its impairment among 383 home-dwelling elderly with cardiovascular diseases (mean age, 80 years). The Mini-Mental State Examination (MMSE) and its changes and the Clinical Dementia Rating (CDR) were used to define cognitive impairment.

RESULTS

At baseline, 0 to 1, 2, and 3 positive titers toward viruses were found in 48 (12.5%), 229 (59.8%), and 106 individuals (27.7%), respectively. MMSE points decreased with increasing viral burden (P=0.03). At baseline, 58 individuals (15.1%) had cognitive impairment, which after adjustments was significantly associated with seropositivity for 3 viruses (hazard ratio, 2.5; 95% CI, 1.3 to 4.7). MMSE score decreased in 150 (43% of 348) during 12-month follow-up. After adjustment for MMSE score at baseline and with 0 to 1 seropositivities as reference (1.0), the hazard ratios were 1.8 (95% CI, 0.9 to 3.6) and 2.3 (95% CI, 1.1 to 5.0) for 2 and 3 seropositivities, respectively. The prevalence of possible or definite dementia according to CDR also increased with viral burden. No significant associations were observed between bacterial burden and cognition.

CONCLUSIONS

Viral pathogen burden of HSV and CMV was associated with cognitive impairment in home-dwelling elderly persons with cardiovascular diseases. The results need to be tested in larger databases, but they may offer a preventable cause of cognitive decline.

Cognitive impairment and nocturnal blood pressure fall in treated elderly hypertensives

OBJECTIVES

We investigated the association between the fall of nocturnal blood pressure (BP) and cognitive impairment in elderly subjects.

METHODS

The study was a cross-sectional survey of 204 elderly subjects who had no cerebrovasucular episodes. Ambulatory BP monitoring and assessments of cognitive functions using the Mini-Mental State Examination (MMSE) were performed at the subjects' homes. We classified, the subjects treated with antihypertensive drugs into three groups: non-dippers (nocturnal fall<10% of the mean day diastolic BP; n=51), normal dippers (10% to less than 20%; n=58), and extreme dippers (20% or more; n=17). The subjects not treated with antihypertensive drugs were also classified as non-dippers (n=40), normal dippers (n=24), and extreme dippers (n=14).

RESULTS

The mean age of participants was 75.2±7.2 years, and 126 (61.7%) were being treated with antihypertensive drugs. In the group of antihypertensive drug users, the number with MMSE≤23 was 30 and the adjusted odds ratio for cognitive impairment in those with an extreme dip in diastolic BP (DBP) was 4.18 (95% CI, 1.07-16.40) in reference to the normal dippers. In contrast, no association was observed between cognitive function and nocturnal BP fall in the group no using antihypertensive drugs.

CONCLUSIONS

Cognitive impairment was associated with an extreme dip in DBP in the antihypertensive drug users only. It remains to be seen whether careful monitoring of nighttime BP as well as daytime BP may reduce the risk of cognitive impairment in antihypertensive drug users.

Perceiving Biological Motion: Dissociating Visible Speech from Walking

Neuropsychological research suggests that the neural system underlying visible speech on the basis of kinematics is distinct from the system underlying visible speech of static images of the face and identifying whole-body actions from kinematics alone. Functional magnetic resonance imaging was used to identify the neural systems underlying point-light visible speech, as well as perception of a walking/jumping point-light body, to determine if they are independent. Although both point-light stimuli produced overlapping activation in the right middle occipital gyrus encompassing area KO and the right inferior temporal gyrus, they also activated distinct areas. Perception of walking biological motion activated a medial occipital area along the lingual gyrus close to the cuneus border, and the ventromedial frontal cortex, neither of which was activated by visible speech biological motion. In contrast, perception of visible speech biological motion activated right V5 and a network of motor-related areas (Broca's area, PM, M1, and supplementary motor area (SMA)), none of which were activated by walking biological motion. Many of the areas activated by seeing visible speech biological motion are similar to those activated while speechreading from an actual face, with the exception of M1 and medial SMA. The motor-related areas found to be active during point-light visible speech are consistent with recent work characterizing the human “mirror” system (Rizzolatti, Fadiga, Gallese, & Fogassi, 1996).

Children's attentional skills 2 years post-traumatic brain injury

This study examined sustained attention abilities 24 months postinjury, in 3 groups of children who had suffered a traumatic brain injury (TBI): (a). mild TBI (n = 24), (b). moderate TBI (n = 31), and (c). severe TBI (n = 14). Three manipulations of the traditional Continuous Performance Test paradigm (CPT) were employed in the study, to delineate factors that might influence CPT performance, including speed of processing, attentional lapses, and stimulus complexity. No significant differences were evident among the TBI groups on a measure of simple reaction time, nor on a CPT version where the interstimulus interval was lengthened. However, there was a significant difference between the mild and severe TBI groups on the most complex task, which required speed, accuracy, and decision making, suggesting that these factors underlie impaired performances previously identified on the CPT in children with severe TBI. These findings have implications for the development of intervention programs for these children.

High frequency stimulation of the subthalamic nucleus has beneficial antiparkinsonian effects on motor functions in rats, but less efficiency in a choice reaction time task

Chronic subthalamic nucleus high frequency stimulation (STN HFS) improves motor function in Parkinson's disease. However, its efficacy on cognitive function and the mechanisms involved are less known. The aim of this study was to assess the effects of STN HFS in hemiparkinsonian awake rats performing different specific motor tests and a cognitive operant task. Unilateral STN HFS applied in unilaterally DA-depleted rats decreased the apomorphine-induced circling behaviour and reduced catalepsy induced by the neuroleptic haloperidol. DA-depleted rats exhibited severe deficits in the operant task, among which the inability to perform the task was not alleviated by STN HFS. However, in a few animals showing less impairment, STN HFS significantly reduced the contralateral neglect induced by the lesion. These results are the first to demonstrate a beneficial effect of STN HFS applied in awake rats on basic motor functions. However, STN HFS appears to be less effective on impaired cognitive functions.

Risk factors for continued cigarette use after subarachnoid hemorrhage

BACKGROUND AND PURPOSE

Cigarette smoking is a risk factor for the formation and rupture of intracranial aneurysms. Few studies have examined predictors of resumption of cigarette smoking after a first episode of subarachnoid hemorrhage (SAH).

METHODS

Of 620 SAH patients treated between July 1996 and November 2002, we prospectively evaluated continued cigarette use in 152 smokers alive at 3 months. Univariate and multivariate logistic regression analyses were used to identify potential demographic, social, and clinical predictors of continued cigarette use, defined as smoking > or =1 cigarette per week in the month before follow-up.

RESULTS

Thirty-seven percent (56 of 152) resumed smoking after their SAH. Patients who continued smoking were younger, were more often black, had begun smoking at an earlier age, and had a higher frequency of prior alcohol or cocaine use and self-reported depression or anxiety than those who quit (all P<0.05). Smoking at < or =16 years of age (odds ratio [OR], 5.88; 95% confidence interval [CI], 2.33 to 14.29), self-reported depression (OR, 5.29; 95% CI, 2.10 to 13.35), and prior alcohol use (OR, 4.51; 95% CI, 1.45 to 14.05) independently predicted continued cigarette use. Smokers had a functional outcome similar to that of nonsmokers at 3 months but were more likely to resume alcohol consumption (OR, 3.88; 95% CI, 1.91 to 7.88).

CONCLUSIONS

More than one third of prior smokers continue to use nicotine after SAH. Young age at smoking onset and a history of depression or alcohol use are risk factors for continued cigarette use. Targeted smoking cessation programs are needed to reduce the high rate of smoking resumption after SAH.

Therapeutic effects of milnacipran (serotonin noradrenalin reuptake inhibitor) on depression following mild and moderate traumatic brain injury

BACKGROUND

The present study investigated the efficacy and safety of milnacipran, a serotonin noradrenalin reuptake inhibitor (SNRI), for the treatment of depression following mild and moderate traumatic brain injury (MMTBI). While other reports have been published on the use of antidepressants such as selective serotonin reuptake inhibitors (SSRIs) and tricyclics for the treatment of depression following MMTBI, no previous study has examined the use of a SNRI for this condition.

METHODS

A six-week open study was conducted using 10 patients (4 males and 6 females) of ages ranging from 28 to 74 years. DSM-IV (diagnostic statistical manual of mental disorders, 4th Ed. American psychiatric association, 1994) was used to diagnose mood disorders. The severity of depression was measured with the 21-item Hamilton rating scale for depression (HAM-D). The cognitive state of the patients was assessed using the mini-mental state examination (MMSE).

RESULTS

The maximum daily milnacipran dosage for the patients ranged from 30 to 150 mg. One patient experienced side effects, but none of the side effects were serious. On the basis of having a decrease in a final HAM-D score of more than 50%, the response rate for the nine patients was 66.7%, while in a final score of 7 or less, the remission rate for the nine patients was 44.4%. Furthermore, significantly greater improvement in cognitive function was seen in patients treated with milnacipran.

CONCLUSION

The results demonstrated that milnacipran is a safe and effective drug for depression following mild and moderate TBI and could be the first choice drug for the treatment of this condition.

Functional imaging of cognition in Parkinson's disease

PURPOSE OF REVIEW

Cognitive deficits that occur even early in the course of Parkinson's disease have received increasing attention in current imaging research. The exact physio-pathological processes mediating the deficits and the complex relationship of cognitive signs and antiparkinsonian treatment are not well understood. A clearer understanding of these mechanisms could potentially influence treatment choices, drug development and, ultimately, patient care.

RECENT FINDINGS

Abnormal networks identified in studies of resting state metabolism in Parkinson's disease represent metabolic markers for remote effects of striato-nigral degeneration. These metabolic changes include subcortico-cortical networks, in particular cognitive cortico-striato-pallidal-thalamocortical loops. Recent brain studies focus on intervention-related brain changes. They illustrate different task-specific changes in brain activation with deep brain stimulation and with levodopa. Variable results of stimulation can be attributed to different effects on segregated cortico-striato-pallidal-thalamocortical loops during stimulation. By contrast, the heterogeneity observed in studies with levodopa possibly reflects the disease-stage and task-specific effects of levodopa. A decline in caudate dopamine modulated basal ganglia outflow appears to contribute to executive dysfunction and to brain activation changes in these loops at early Parkisnon's disease stages, while mesocortical degeneration mediated increases of inefficient dorsolateral prefrontal cortex activation may display a feature of more advanced disease stages only.

SUMMARY

Despite evidence for the role of dopamine and cortico-striato-pallidal-thalamocortical loops in cognition, the specific contributions of mesocortical dopamine depletion and striatal dysfunction with downstream consequences on the loops remain to be separated. Additionally, more research is needed into the role of non-dopaminergic pathology in cognitive decline in Parkinson's disease.

Familial bipolar disorder and multiple sclerosis: a three-generation HLA family study

The coexistence of bipolar disorder (BD) and multiple sclerosis (MS) is well known. Manic symptoms may represent initial symptoms of MS, at least in some cases, and follow the MS-HLA phenotype frequencies. The purpose of this study was to examine the possible relation of BD and MS based on an HLA family study of a woman with BD and comorbid MS, with family history of BD. Five members of the family from three generations (the patient, her mother, her brother, and her two daughters) were examined regarding the two disorders and the HLA class I and II specificities, performed by serology and molecular techniques. Her deceased father, her brother, and her older daughter suffered from BD. Moreover, in her brother, BD and MS comorbidity was diagnosed. The three affected members and the nonaffected grandmother share the same class I and II, HLA-A2, B18, CW8, DR2, DQ1 haplotype. The shared class II, HLA-DR2, DQ1 haplotype among affected individuals, which is well known to be associated with MS in Caucasians, suggests a possible susceptibility locus for BD, mapped on chromosome 6, very close to the HLA region, underlying the clinical comorbidity of the two disorders.

Brain injury in battered women

The goals of the present study were to examine (a) whether battered women in a sample of both shelter and nonshelter women are sustaining brain injuries from their partners and (b) if so, whether such brain injuries are associated with partner abuse severity, cognitive functioning, or psychopathology. Ninety-nine battered women were assessed using neuropsychological, psychopathology, and abuse history measures. Almost three quarters of the sample sustained at least 1 partner-related brain injury and half sustained multiple partner-related brain injuries. Further, in a subset of women (n = 57), brain injury severity was negatively associated with measures of memory, learning, and cognitive flexibility and was positively associated with partner abuse severity, general distress, anhedonic depression, worry, anxious arousal, and posttraumatic stress disorder symptomatology.

Traumatic brain injury and its effects on synaptic plasticity

Animal models have been used to simulate the effects of human head trauma. Some of these models have been further utilized to explore how trauma affects specific mechanisms of synaptic plasticity, a cellular model for memory consolidation. Unfortunately, these studies have been more limited in number in spite of their importance for understanding alterations in synaptic plasticity and memory impairments in trauma patients. Research in this area includes well characterized trauma models, genetically engineered animals and neuroprotective studies. One largely ignored but important idea that is entertained here is that trauma may be a crucial aetiological factor for the loss of potassium homeostasis. Moreover, high extracellular potassium has been shown to promote abnormal expression of hippocampal synaptic plasticity due to K(+)-induced glutamate release, thus showing important relationships among trauma, glia, potassium and synaptic plasticity. Collectively, this mini review surveys investigations of head trauma involving altered mechanisms of synaptic plasticity and how trauma may be related to increased risk for dementia.

Neurocognitive rehabilitation for schizophrenia

A critical review of randomized, controlled trials of extended programs of neurocognitive rehabilitation for the cognitive deficits characteristic of schizophrenia conducted between the years 2000 to 2002 was completed. Over the past several years, two models of cognitive rehabilitation have emerged. In one model, labeled "cognitive remediation," cognitive deficits are treated directly through repeated practice and acquisition of compensatory strategies on cognitive exercises designed to engage underfunctioning brain systems. In a second model, labeled "cognitive adaptation," neurocognitive deficits are addressed through modification of the patients' environment to allow patients to bypass their deficits. Results revealed that a range of cognitive remediation strategies varying widely along dimensions of duration, intensity, method, target of behavioral intervention, and clinical status of participants produced improvements on measures of working memory, emotion perception, and executive function distinct from those trained during remediation. No effects were evident in secondary verbal or nonverbal memory. Results of two pilot studies using functional magnetic resonance imaging to assess changes in task-evoked brain activation have revealed that these interventions may produce changes in several functionally relevant neural systems in a subset of patients. Results from studies of standardized cognitive adaptation interventions have indicated that these treatments can produce improvements in symptoms, psychosocial status, and relapse rates. A variety of approaches for future research are also discussed.

Profiles of neuropsychologic function in schizophrenia

In this article, the author reviews basic neuropsychologic issues in the study of schizophrenia. The first issue is whether cognitive dysfunction reflects a degenerative process or is a core feature of the disorder. Evidence demonstrating that cognitive difficulties are present at illness onset and are not caused by medication, illness progression, or other nonspecific factors is reviewed. The second question is less easily answered and deals with whether cognitive difficulties represent generalized dysfunction or differential deficits in specific neurocognitive domains. One difficulty in answering this question is the heterogeneous nature of the disorder. Clinical and cognitive subtyping approaches to reducing heterogeneity are discussed, with the conclusion that cognitive approaches hold the most promise for understanding subtype differences in neurobiologic substrates. Finally, the relation of cognitive ability to functional outcome is described, and it is explained why there is a resurgent interest in remediation efforts. The article closes with suggestions for future directions.

Continuing challenges for computer-based neuropsychological tests

A number of issues critical to the development of computer-based neuropsychological testing systems that remain continuing challenges to their widespread use in occupational and environmental health are reviewed. Several computer-based neuropsychological testing systems have been developed over the last 20 years, and they have contributed substantially to the study of neurologic effects of a number of environmental exposures. However, many are no longer supported and do not run on contemporary personal computer operating systems. Issues that are continuing challenges for development of computer-based neuropsychological tests in environmental and occupational health are discussed: (1) some current technological trends that generally make test development more difficult; (2) lack of availability of usable speech recognition of the type required for computer-based testing systems; (3) implementing computer-based procedures and tasks that are improvements over, not just adaptations of, their manually-administered predecessors; (4) implementing tests of a wider range of memory functions than the limited range now available; (5) paying more attention to motivational influences that affect the reliability and validity of computer-based measurements; and (6) increasing the usability of and audience for computer-based systems. Partial solutions to some of these challenges are offered. The challenges posed by current technological trends are substantial and generally beyond the control of testing system developers. Widespread acceptance of the "tablet PC" and implementation of accurate small vocabulary, discrete, speaker-independent speech recognition would enable revolutionary improvements to computer-based testing systems, particularly for testing memory functions not covered in existing systems. Dynamic, adaptive procedures, particularly ones based on item-response theory (IRT) and computerized-adaptive testing (CAT) methods, will be implemented in new tests that will be more efficient, reliable, and valid than existing test procedures. These additional developments, along with implementation of innovative reporting formats, are necessary for more widespread acceptance of the testing systems.

Stability of formal thought disorder and referential communication disturbances in schizophrenia

This study examined the degree to which different types of communication disturbances in the speech of 48 schizophrenia patients and 28 controls were variable and state related versus stable and traitlike. Clinically rated formal thought disorder and 5 types of referential disturbance showed substantial stability within participants over time. The sixth type of referential disturbance, the vague reference, was not stable over time. Formal thought disorder was associated with the severity of core psychotic symptoms in patients. whereas referential disturbances showed little or no association with positive or negative symptom severity. Furthermore, changes in psychotic symptoms over time were accompanied by corresponding changes in formal thought disorder but not referential disturbances. These results support the idea that some types of referential disturbances are traitlike and may be reflective of vulnerability as well as manifest illness.

Return to play following sports-related mild traumatic brain injury: the role for neuropsychology

Cerebral concussions frequently occur at all levels of athletic competition. The effects from these concussions can be transient or may lead to chronic, debilitating symptoms. A growing literature has established that neuropsychological tests are useful in detecting the subtle neurocognitive changes that occur following concussions. The identification of these deficits and subsequent recovery of function can be important components in making return-to-play (RTP) decisions. This article describes the emergence of neuropsychology in sports medicine, discusses the context in which RTP decisions are made, outlines factors that are important to RTP decisions, and presents a model that views the RTP decision as a dynamic risk-benefit analysis that involves complex interactions among variables. It is argued that neuropsychology has a unique, but not exclusive, role in the decision making process. Implications for future research are discussed.

Current issues in the identification, assessment, and management of concussions in sports-related injuries

The recent literature has focused on the need for appropriate identification, assessment, and management of sports-related concussion. This article addresses current issues in the prevalence and assessment of sports-related concussion. Despite a paucity of research on female athletes and youth athletes, there is evidence that female athletes are at higher risk for injury than males and that concussions may affect children and young adolescents differently than older adolescents and adults. Sideline, baseline, and postconcussion assessments have become prevalent in documenting preinjury and postinjury performance, tracking recovery rates, and assisting return-to-play decisions. New computerized assessment procedures are growing in popularity and use. Future directions in the assessment and management of sports-related concussion include increased research on prevalence rates and effects of concussions for females and youth athletes, educating parents of youth athletes as well as family physicians on the importance of baseline and postconcussion cognitive assessments, and further validation of computerized assessment measures.

Recency and frequency of soccer heading interact to decrease neurocognitive performance

This study investigated the role of heading recency interacting with heading frequency in determining neuropsychological deficits associated with heading the ball during soccer play. Sixty-four high-ability male soccer players ages 16 to 34 completed the California Verbal Learning Test (CVLT), the Trailmaking Test, the Paced Auditory Serial Addition Test (PASAT), the Facial Recognition Test, the Rey-Osterrieth Complex Figure, and the Shipley Scales. Heading recency interacted with heading frequency, such that players with the highest self-reported estimates of heading who also experienced heading within the previous 7 days scored significantly lower on CVLT, Shipley, Trailmaking, and PASAT than other combinations of heading and recency. Although strict ball-to-head contacts could not be isolated as sufficient to cause this interaction, these results increase the weight of evidence that heading behavior is problematic for causing at least transient cognitive impairment.

The neuropsychology of repeated 1- and 3-meter springboard diving among college athletes

This study examined the neuropsychological effects of repeated springboard diving. It was hypothesized that the impact velocity, which can range from 20 to 30 mph, and accompanying deceleration in the water may lead to concussions and affect the diver's cognitive function. Six varsity National Collegiate Athletic Association Division 1 springboard divers participated in the study. Each diver performed a total of 50 practice dives from either the 1- or 3-m springboard. After each set of 10 dives, the participants were immediately evaluated at poolside using the Symbol Digit Modalities Test, the Stroop Color Word Test, and the Trail Making Test B. Baseline testing revealed, consistent with their athletic specialty, clear neurocognitive strengths among the divers on tests sensitive to proprioception, motor speed, and visual-spatial organization. Results from the serial assessments indicated no detectable neuropsychological deficits among competitive divers compared to baseline testing. Skilled diving at the collegiate level appears to be a safe sport and water appears to present the perfect medium for gradual deceleration. More studies, however, are warranted for 5-, 7.5-, and 10-m platform diving since the impact velocity of the diver from these heights is higher.

Computer-based assessment of sports-related concussion

Sports-related concussion has received considerable attention from neuropsychologists, athletic trainers, team coaches, physicians, families, and athletes. In this context, researchers have recently developed computer programs for the assessment of sports-related concussion. Computer-based assessment of sports-related concussion saves time, allows for team baseline testing, and can be easily incorporated into the sports medicine environment. This article reviews the advantages and limitations of computer-based assessment of sports-related concussion. Within a well-coordinated concussion management program that includes input from a neuropsychologist, computer-based assessment of sports-related concussion will soon be the most common approach for assessing concussion in athletes.

Psychological aspects of serious head injury in the competitive athlete

In addition to the physical aspects of athletic injury, there are psychological aspects to consider. These are important during all phases of injury management: the acute injury, the rehabilitative process, and the return-to-play progression. Emotional disturbances are often associated with mild traumatic brain injury (mTBI) both directly and indirectly. Evaluating the athlete with mTBI can be made more difficult by the need to distinguish the physical and the emotional effects of injury and to differentiate the emotional factors directly related to the brain injury from those that arise indirectly (eg, reaction to being held out of play). This article discusses some of the psychological issues related to evaluating the head injured athlete.

Cognitive presentation of multiple sclerosis: evidence for a cortical variant

BACKGROUND

Although neuropsychiatric complications are well recognised, the presentation of multiple sclerosis with cognitive or neuropsychiatric symptoms has generally been considered a rare occurrence and to reflect subcortical pathology.

OBJECTIVES

To document the clinical, neuropsychological, and radiological features of six cases of cognitive presentation of multiple sclerosis, to review the relevant literature, and to propose a possible cortical basis for this clinical presentation.

SUBJECTS

Six patients (five women; age range 38 to 60 years) presented to the memory and cognitive disorders clinic in Cambridge with an initially undiagnosed cognitive/neuropsychiatric syndrome. All underwent neuropsychological evaluation, brain imaging, and ancillary investigations to establish a diagnosis of multiple sclerosis.

RESULTS

The six cases all had a progressive dementia syndrome with prominent amnesia, often accompanied by classic cortical features including dysphasia, dysgraphia, or dyslexia. Mood disturbance was ubiquitous and in three patients there was a long history of preceding severe depression. All six developed characteristic physical signs on follow up, with marked disabilities. A review of 17 previously reported cases highlighted the prominence of memory impairment and depression in the early stages.

CONCLUSIONS

On clinical, pathological, and radiological grounds, the neuropsychiatric presentation of multiple sclerosis may represent a clinicopathological entity of "cortical multiple sclerosis." Failure to recognise this will delay diagnosis and may expose patients to potentially dangerous and invasive investigation. Because the neuropsychiatric features of cortical multiple sclerosis are a major cause of handicap, their early recognition may be particularly important in view of emerging treatments.

Practitioner review: computerized assessment of neuropsychological function in children: clinical and research applications of the Cambridge Neuropsychological Testing Automated Battery (CANTAB)

BACKGROUND

Computers have been used for a number of years in neuropsychological assessment to facilitate the scoring, interpretation, and administration of a variety of commonly used tests. There has been recent interest in applying computerized technology to pediatric neuropsychological assessment, which poses unique demands based on the need to interpret performance relative to the child's developmental level.

FINDINGS

However, pediatric neuropsychologists have tended to implement computers in the scoring, but not administration, of tests. This trend is changing based on the work of experimental neuropsychologists who frequently combine data obtained from test batteries with lesion or neuroimaging data allowing descriptions of brain-behavior relations to be made with increasing confidence. One such battery is the Cambridge Neuropsychological Testing Automated Battery (CANTAB), and current studies in which the CANTAB has been used to measure executive functions in children are reviewed.

CONCLUSIONS

Computerized batteries of this type can record aspects of performance that are difficult for psychometrists to achieve, and these may reflect activity in developing neural networks with more sensitivity than can be achieved with traditional tests. However, before computerized test administration becomes a routine part of pediatric neuropsychological assessment, several obstacles must be overcome. Despite these limitations, it is concluded that computerized assessment can improve the field by facilitating the collection of normative and clinical data.

Reports of head injury and symptom knowledge among college athletes: implications for assessment and educational intervention

OBJECTIVE

To identify the prevalence of head injuries and related symptoms among college athletes and examine knowledge of head injury consequences and behavioral tendencies of athletes in the presence of symptoms.

DESIGN

Retrospective survey.

PARTICIPANTS

A total of 461 male and female athletes beginning competitive play at the University of Akron (Akron, OH) during the years 1995 to 2001.

MAIN OUTCOME MEASURES

Responses to survey questions were analyzed to determine the frequency of concussions and injury-related symptoms (eg, dizziness, headache, nausea or vomiting) in addition to behavioral responses in the presence of certain symptoms (eg, playing with headache, failure to report symptoms while playing). Written responses to queries regarding symptom knowledge were analyzed for thematic content and were used to identify deficiencies in signs and symptoms of concussion.

RESULTS

Nearly 32% of all athletes had experienced a blow to the head causing dizziness, with over 1/4 confirming various somatic symptoms following a blow to the head (eg, seeing stars, nausea or vomiting, head pain). Continuing to play despite symptom presence was noted (eg, dizziness, 28.2%; headache, 30.4%), with 19.5% reporting a concussion diagnosis. Knowledge of head injury consequences was found to be deficient, with 56% indicating no knowledge of the possible consequences following a head injury. Of those providing responses, the majority reflected awareness of cognitive (eg, memory problems) and physical (eg, brain damage) consequences.

CONCLUSIONS

A sizable number of athletes may enter collegiate play with a previous concussion diagnosis, and many more are likely to have experienced symptoms suggestive of a mild head injury. Of considerable concern is the tendency to play while symptomatic (eg, headache, dizziness) and the failure to report symptoms while playing--especially among football players (25.2%). The apparent deficiency in athlete knowledge of head injury consequences raises concern regarding athlete recognition of potentially problematic symptoms and represents an important area for educational intervention.

Preservation of cognitive function after long-term tetraplegia

The claim of a significant relationship between pulmonary peak expiratory flow rate and cognitive decline in normal aging is bound to raise the question of whether accelerated cognitive decline would be an automatic consequence of long-term tetraplegia, with its significant effects on normal respiratory function. We present a case series of three persons with long-term tetraplegia (11, 15, and 21 yr) comparing their cognitive test results (short-term and working memory, the ability to inhibit interference, and cognitive processing speed) with scores for age-matched noninjured adults. Results showed that long-term tetraplegia, even with compromised respiration, does not inevitably lead to decline in fundamental cognitive functions relative to age-matched noninjured controls.

Head injury as a risk factor for Alzheimer's disease: the evidence 10 years on; a partial replication

OBJECTIVE

To determine, using a systematic review of case-control studies, whether head injury is a significant risk factor for Alzheimer's disease. We sought to replicate the findings of the meta-analysis of Mortimer et al (1991).

METHODS

A predefined inclusion criterion specified case-control studies eligible for inclusion. A comprehensive and systematic search of various electronic databases, up to August 2001, was undertaken. Two independent reviewers screened studies for eligibility. Fifteen case-control studies were identified that met the inclusion criteria, of which seven postdated the study of Mortimer et al.

RESULTS

We partially replicated the results of Mortimer et al. The meta-analysis of the seven studies conducted since 1991 did not reach significance. However, analysis of all 15 case-control studies was significant (OR 1.58, 95% CI 1.21 to 2.06), indicating an excess history of head injury in those with Alzheimer's disease. The finding of Mortimer et al that head injury is a risk factor for Alzheimer's disease only in males was replicated. The excess risk of head injury in those with Alzheimer's disease is only found in males (males: OR 2.29, 95% CI 1.47 to 2.06; females: OR 0.91, 95% CI 0.56 to 1.47).

CONCLUSIONS

This study provides support for an association between a history of previous head injury and the risk of developing Alzheimer's disease.

A waitlist control-group study of cognitive, mood, and quality of life outcome after posteroventral pallidotomy in Parkinson disease

OBJECT

The aim of this study was to examine neuropsychological outcome from unilateral posteroventral pallidotomy (PVP) in Parkinson disease while controlling for confounding factors such as test practice and disease progression.

METHODS

Participants underwent baseline and 2-month follow-up assessments of cognition, quality of life, mood, and motor functioning. The surgery group (22 patients) underwent PVP (15 left, seven right) after baseline assessment. The waitlist group (14 patients) underwent PVP after follow up. At follow up, the left PVP group exhibited a decline on verbal measures of learning, fluency, working memory, and speeded color naming. The incidence of significant decline on these measures after left PVP ranged from 50 to 86%. The right PVP group did not exhibit a significant cognitive decline, but fluency did decline in 71% of patients who underwent right PVP. Participants who underwent PVP reported better bodily pain and social functioning at follow up than participants in the waitlist group. Improved bodily pain was evident for 62% of the surgery group, and social functioning improved for 19%. Surgery did not alter reported physical functioning or mood. Dyskinesia improved after surgery, but there were no improvements in "on-state" manual dexterity or handwriting.

CONCLUSIONS

Most patients who underwent left PVP exhibited declines in learning, fluency, working memory, and speeded color naming. Accounting for retesting effects altered the magnitude of these declines by up to one quarter of a standard deviation, but did not increase the breadth of postsurgical neuropsychological decline beyond that typically reported in the literature. It was found that PVP improved dyskinesia, bodily pain, and social functioning, but did not lead to improvement on other objective and self-reported measures of motor functioning.

Emotion processing in chimeric faces: hemispheric asymmetries in expression and recognition of emotions

Since the discovery of facial asymmetries in emotional expressions of humans and other primates, hypotheses have related the greater left-hemiface intensity to right-hemispheric dominance in emotion processing. However, the difficulty of creating true frontal views of facial expressions in two-dimensional photographs has confounded efforts to better understand the phenomenon. We have recently described a method for obtaining three-dimensional photographs of posed and evoked emotional expressions and used these stimuli to investigate both intensity of expression and accuracy of recognizing emotion in chimeric faces constructed from only left- or right-side composites. The participant population included 38 (19 male, 19 female) African-American, Caucasian, and Asian adults. They were presented with chimeric composites generated from faces of eight actors and eight actresses showing four emotions: happiness, sadness, anger, and fear, each in posed and evoked conditions. We replicated the finding that emotions are expressed more intensely in the left hemiface for all emotions and conditions, with the exception of evoked anger, which was expressed more intensely in the right hemiface. In contrast, the results indicated that emotional expressions are recognized more efficiently in the right hemiface, indicating that the right hemiface expresses emotions more accurately. The double dissociation between the laterality of expression intensity and that of recognition efficiency supports the notion that the two kinds of processes may have distinct neural substrates. Evoked anger is uniquely expressed more intensely and accurately on the side of the face that projects to the viewer's right hemisphere, dominant in emotion recognition.

A retrospective study of premorbid ability and aging differences in cognitive clusters of schizophrenia

This retrospective, cross-sectional study evaluated whether age-related differences in patterns of cognitive deficit exist among four cognitively based schizophrenia subgroups. These subgroups had previously been identified through cluster analyses of a battery of abstraction and problem-solving tests in large samples. Evaluation of estimated premorbid intellectual ability and postmorbid cognitive functioning stratified by decade from the twenties through the fifties revealed different patterns across the schizophrenia subgroups and a clinical comparison sample. A near normal cognitive subgroup demonstrated relatively high premorbid intellectual ability and a pattern of age differences similar to the comparison sample, with the exception of deficits on the Wisconsin Card Sorting Test that were detectable in the twenties and remained stable thereafter. In contrast, a subgroup characterized by severe, pervasive cognitive deficit demonstrated low premorbid intellectual ability and extremely low test scores across the four decades studied. The remaining clusters were characterized by moderate cognitive impairment and showed age differences suggestive of a decline in cognitive function around the time of illness onset that remained stable. Results provide further support for the validity of these subgroups and encourage continued efforts to identify cognitively based candidate schizophrenia subtypes.

Pulse width is associated with cognitive decline after thalamic stimulation for essential tremor

The present study sought to identify predictors of cognitive decline after thalamic deep brain stimulation (DBS) for essential tremor (ET). Twenty-seven patients (55%) with ET demonstrated mild cognitive decrements relative to pre-surgical baseline (ET-D), whereas 22 patients (45%) were classified as neuropsychologically stable (ET-S). The ET-D and ET-S groups were comparable in terms of baseline demographic, disease, and neuropsychological characteristics, as well as post-surgical motor outcomes. However, the ET-D group had significantly higher pulse width (PW) stimulator settings, and a greater proportion of ET-D than ET-S patients underwent left in comparison to right thalamic stimulation. A subsequent step-wise discriminant function analysis revealed that disease onset after age 37 years and higher PW settings (>or=120 micros) were the strongest predictors of post-surgical cognitive decline in this sample. Findings indicate that although relatively higher PW settings might afford optimal tremor control in some patients, the corresponding risk of mild, probably often subclinical, cognitive morbidity must be weighed accordingly.

Odor identification deficits in diffuse lewy body disease

OBJECTIVES

To describe odor identification performance in patients with diffuse Lewy body disease and determine the clinical utility of odor identification tests in distinguishing diffuse Lewy body disease from Alzheimer disease.

BACKGROUND

The presence of olfactory deficits, especially odor identification deficits, has been well established in both Alzheimer disease and Parkinson disease. The presence of olfactory deficits in diffuse Lewy body disease is also likely given the overlap of clinical symptoms and neuropathology with Alzheimer disease and Parkinson disease. However, odor identification abilities have not been described previously in diffuse Lewy body disease.

METHODS

Nine patients from a clinic sample with diffuse Lewy body disease and nine carefully matched patients with Alzheimer disease were administered an odor identification task as part of their neuropsychologic evaluations.

RESULTS

Patients with diffuse Lewy body disease performed significantly worse than patients with Alzheimer disease on the odor identification test.

CONCLUSIONS

Odor identification deficits may be more prevalent and severe in people with diffuse Lewy body disease than in people with Alzheimer disease, and olfactory testing may be useful in antemortem differential diagnosis of the two disorders.

Verbal declarative memory dysfunction in schizophrenia: from clinical assessment to genetics and brain mechanisms

The recent literature on the neuropsychology of schizophrenia has emphasized memory deficits as a key area of impairment. Abnormalities in the medial temporal lobe, a brain region crucial for long-term memory formation, have also consistently been reported. We conducted a comprehensive review of verbal declarative memory (VDM) in schizophrenia with the aim of systematically addressing the nature of this impairment. We conclude that verbal declarative memory is significantly impaired in schizophrenia and is largely accounted for by deficits in the encoding stage. Subtle impairments in increased rates of forgetting are present, but are mild compared with those in amnestic disorders. Impairment in other cognitive domains studied thus far (e.g., attention), medication effects, or fluctuations in symptoms do not completely account for the deficit. VDM is among the most impaired neurocognitive domains in schizophrenia (along with attention and executive functions). Milder encoding deficits are present in high-risk subjects and non-psychotic relatives of individuals with schizophrenia suggesting that components of the deficit are associated with a genetic vulnerability to the illness, and are independent of the frank psychotic illness. Furthermore, VDM is observed in individuals experiencing their first-psychotic episode and it remains fairly consistent over time. Preliminary imaging studies and other work suggest abnormalities in prefrontal-hippocampal processing networks. Future work should emphasize delineating specific information processing components contributing to the deficit. This would allow imaging studies to determine which brain regions contribute to specific information processing deficits in schizophrenia.

A brief neuropsychological testing battery for evaluating patients with schizophrenia

Current conceptualizations of schizophrenia include neurocognitive impairment, particularly in aspects of attention, memory, and executive functioning. Evaluation of these cognitive abilities typically involves use of comprehensive batteries which may take up to six hours to complete. The current study examined the effectiveness of a briefer battery to detect cognitive impairments usually seen in schizophrenia as established by previous studies using more lengthy and labor intensive protocols. The current study involved 61 outpatients with schizophrenia who were separated into three subgroups: paranoid type (n = 20), undifferentiated type (n = 21), and schizoaffective (n = 20). The majority of the patients were male (61%), African-American (52%), and of low socio-economic status. The mean age was 41.4 years (SD = 8.8), and the mean years of education was 11.7 (SD = 6.8). For the overall sample, results revealed mild to moderate impairments in memory, construction, concept formation, response set maintenance, psychomotor speed, and visual speed of information processing. Post-hoc analyses revealed significant differences between subgroups on Similarities and psychomotor speed, with the undifferentiated group performing more poorly than the paranoid or schizoaffective groups. In conclusion, the current brief battery minimized respondent burden in terms of both time demands and level of task complexity. However, it was also sensitive enough to capture many of the same cognitive weaknesses as those reported when using more labor-intensive neuropsychological test protocols.

Age and task parameters in continuous performance tests for preschoolers

66 children (M=56.2 mo., SD=10.9), recruited from preschool and daycare centers, were administered two continuous performance tests, one auditory and one visual. Both tests utilized a format with one target and one nontarget. Interstimulus interval was fixed at 1350 msec. for the visual test and 5000 msec. for the auditory test. The visual test produced greater rates of omission and commission errors than the auditory test. Age was significantly related to mean reaction time and response variability for both tests; however, the visual test produced an unexpected pattern of increasing response time across age groups. On both tests omission rates improved significantly with age, while commission rates were consistent across ages 3-6 years. When considering continuous performance test paradigms for preschoolers, 3-yr.-olds may need at least a 4000-msec. interstimulus interval to make a choice for the stimulus cue. Hits following an interstimulus interval shorter than 1400 msec. may reflect younger preschoolers' response to a previous stimulus.

Recovery from mild head injury in pediatric populations

This article provides an overview of the diagnosis, classification, and pathophysiology of mild head injury (MHI) in children. The difficulties associated with determination of MHI severity are outlined. Also, recently published research pertaining to pediatric MHI is reviewed. The recent research pertaining to MHI in children is generally consistent with the conclusions reached by the authors of the most recent comprehensive review, which reported that children who have suffered MHI often experience a symptomatic phase that could extend up to a few months, but these symptoms usually resolve. Numerous preinjury variables have been identified, including premorbid learning and behavior problems, disadvantaged socioeconomic status, premorbid neurodevelopmental abnormalities, and adverse family conditions, that appear to explain the persistence of some symptoms experienced by a subset of children with MHI. Directions for future research are provided.

Psychogenic nonepileptic seizures: review and update

The population incidence of psychogenic nonepileptic seizures (PNES) may be only 4% that of epilepsy, but many patients with PNES have a tendency to seek medical attention, and PNES make up a larger share of the workload of neurologists and emergency and general physicians. Although a great number of publications describe how PNES can be distinguished from epileptic seizures, it usually takes several years to arrive at this diagnosis, and three-quarters of patients (with no additional epilepsy) are treated with anticonvulsants initially. However, the management of PNES as epileptic seizures can lead to significant iatrogenic harm. Moreover, the failure to recognize the psychological cause of the disorder detracts from addressing associated psychopathology and enhances secondary somatization processes. This review provides an overview of studies of the diagnosis, etiology, treatment, and prognosis of PNES. Physicians should always consider PNES in the differential diagnosis of a seizure disorder. If a diagnosis of PNES is possible, or a diagnosis of epilepsy in doubt, a clear diagnostic categorization should be sought. This should involve the assessment of the patient by a physician versed in the diagnosis of seizure disorders and, in many cases, the documentation of a typical seizure by video-EEG. Outcome may be improved if the diagnosis is more actively sought, made earlier, and communicated more convincingly.

Cognitive dysfunction following adjuvant chemotherapy for breast cancer: two case studies

PURPOSE/OBJECTIVES

To describe the cognitive dysfunction experienced by two women after they received adjuvant chemotherapy for breast cancer and to discuss the potential role of changes in reproductive status and depression in the development of cognitive dysfunction.

DATA SOURCES

Journal articles, research data, and clinical experience.

DATA SYNTHESIS

Following chemotherapy, 17%-50% of women with breast cancer experience cognitive dysfunction that may include decrements in memory, attention, and psychomotor efficiency. One mechanism that may contribute to cognitive dysfunction involves changes in reproductive status resulting from chemotherapy. Additionally, the presence of depression may confound the experience of cognitive dysfunction.

CONCLUSIONS

A comprehensive description of cognitive dysfunction and improved understanding of the interrelationships among cognitive dysfunction, reproductive hormone levels, and depression in women with breast cancer receiving adjuvant chemotherapy may hasten the development of interventions for the management of cognitive dysfunction.

IMPLICATIONS FOR NURSING

Nurses should teach women with breast cancer and their families about the potential for cognitive dysfunction after chemotherapy so the problem can be recognized and interventions can be implemented to help women compensate for the dysfunction.

Gourmand savants and environmental determinants of obesity

Obesity is an embodiment of a multifactorial problem with several intermediates in its casual pathway. Virtually all who have written on obesity have responded to four inter-related factors: genetic, perinatal, environmental, and consumption-expenditure energy imbalance. The message to take home is that while a molecular description of each participant of the obesity machinery seems achievable in principle, a complex model describing all of them is currently beyond our grasp. That is why the eradication of the obesity epidemic is seen in a more precise neuropsychological description of what is wrong with each subset of patients. This review proposes that the neuropsychiatric experience might be the most fundamental for it could help to refocus the view of obesity from 'traditional' environmental factors and lifestyle changes to those dominated by a more 'individual-centred' perspective in which different modes of causal attribution are appropriate. This review advocates the idea of environmental dependency as a determinant of obesity, which has been an important idea in neurosciences for more than 30 years with roots in three important areas: psychological, neuropsychiatric, and experimental. The neuropsychology of obesity is yet to become part of today's agenda of obesity research.

Cognitive changes with coronary artery disease: a prospective study of coronary artery bypass graft patients and nonsurgical controls

BACKGROUND

Cognitive impairment after coronary artery bypass grafting (CABG) is well recognized, but previous investigations have been limited by lack of an appropriate control group. We compared changes in cognitive performance at 3 and 12 months after CABG with those in a control group of patients with comparable risk factors for coronary artery disease (CAD) who had not undergone surgery.

METHODS

Patients undergoing CABG (n = 140) and demographically similar nonsurgical control subjects with CAD (n = 92) completed baseline neuropsychological assessment and were followed prospectively at 3 and 12 months. Cognitive function was evaluated with a battery of neuropsychological tests assessing the cognitive domains of attention, language, verbal and visual memory, visuoconstruction, executive function, and psychomotor and motor speed.

RESULTS

The CABG patients who were tested in their hospital rooms before surgery had lower scores for timed tests; however, after adjustment for demographic variables and testing location there were no statistically significant differences between the CABG and nonsurgical control subjects in baseline neuropsychological test performance. Both groups improved from baseline to 3 months; the only statistically significant group difference was a greater improvement in the CABG group with regard to verbal memory. At 12 months there were no statistically significant differences between the two groups.

CONCLUSIONS

The prospective longitudinal neuropsychological performance of patients with CABG did not differ from that of comparable nonsurgical control subjects with CAD at 3 months or 1 year after base line examination. This suggests that the previously reported cognitive decline during the early postoperative period after CABG is transient and reversible. Continued follow-up will determine whether a specific "late decline" occurs in CABG patients but not in nonsurgical control subjects with similar risk factors for cardiovascular and cerebrovascular disease.

Amyloid beta accumulation in axons after traumatic brain injury in humans

OBJECT

Although plaques composed of amyloid beta (AD) have been found shortly after traumatic brain injury (TBI) in humans, the source for this Abeta has not been identified. In the present study, the authors explored the potential relationship between Abeta accumulation in damaged axons and associated Abeta plaque formation.

METHODS

The authors performed an immunohistochemical analysis of paraffin-embedded sections of brain from 12 patients who died after TBI and from two control patients by using antibodies selective for Abeta peptides, amyloid precursor protein (APP), and neurofilament (NF) proteins. In nine brain-injured patients, extensive colocalizations of Abeta, APP, and NF protein were found in swollen axons. Many of these immunoreactive axonal profiles were present close to Abeta plaques or were surrounded by Abeta staining, which spread out into the tissue. Immunoreactive profiles were not found in the brains of the control patients.

CONCLUSIONS

The results of this study indicate that damaged axons can serve as a large reservoir of Abeta, which may contribute to Abeta plaque formation after TBI in humans.

Functional transcranial Doppler sonography as a tool in psychophysiological research

Functional transcranial Doppler sonography (fTCD) allows the noninvasive and uncomplicated registration of intracranial blood flow parameters under defined conditions of stimulation. Although local distribution patterns of regional blood perfusion can be measured with high spatial resolution through neuroimaging methods (e.g., PET or SPECT), these methods are limited by their low temporal resolution. The high temporal resolution provided by fTCD, however, allows the recording of the dynamic component of cerebral blood perfusion by continuously measuring the cerebral blood flow velocity in the basal cerebral arteries. Hence, this method is especially appropriate for the investigation of fast neuronal activation processes, which are generally accompanied by changes in local blood perfusion. In this review, we present methodical issues regarding fTCD, as well its application in the field of psychology, especially psychophysiology. The relevant studies available to date investigate processes of attention and perception, higher cognitive functions, and emotional and psychomotor processes. Considering the current state of methodology and research, fTCD can be seen to be an important complement to the other psychophysiological methods for studying brain function.