Literature suggests that aspects of social cognition, as well as neuropsychological difficulties play a key role in the development and maintenance of Post-Traumatic Stress Disorder (PTSD) symptoms in brain injury survivors. The present study aimed to explore the direct relationship between measures of neuropsychological function and social cognition, and psychological outcomes related to PTSD. A quantitative, cross-sectional, correlational design was employed, using correlational and multivariate regression methods of analysis. Forty-nine adult brain injury survivors were administered a range of measures of neuropsychological function (memory, executive function and attention); social cognition (Mentalization, emotion recognition, social judgment making and emotion-based decision-making) and Psychological outcomes related to PTSD (depression, anxiety, anger and PTSD symptoms). Significant relationships were found between measures of Mentalization, attention and memory, and symptoms relating to depression and PTSD. Selective visual attention and Mentalization were found to account for 37% of the relevant variance for depressive symptoms, while Mentalization and delayed memory recall accounted for 24% of the relevant variance for PTSD symptoms. Different measures of Mentalization showed unexpected correlation directions, which had significant implications for the role Mentalization might play in maintaining PTSD symptoms. The findings suggest an association between aspects of social cognition and neuropsychological functioning, and psychological outcomes related to PTSD. It is thought that impairments in these areas could play a role in maintaining these outcomes in Acquired Brain Injury survivors.

Cognitive complaints are common following an acquired brain injury and require careful assessment in order to guide treatment and care. There is a need for brief, comprehensive and psychometrically valid tests of cognitive function that can be used in neuro-rehabilitation services by a range of health professionals. The Short Parallel Assessments of Neuropsychological Status (SPANS) was purpose-designed to meet this need. The current study assessed the reliability, discriminative validity and factor structure of the SPANS. Participants were 61 people with an acquired brain injury, 35 people with a long-term neurological condition, and 122 healthy controls. Cronbach’s alphas were adequate to excellent for the clinical groups though poor for the healthy controls due to limited variance in the scores. Receiver operating characteristic curves showed that SPANS indices were significantly able to discriminate between people with a neurological condition and healthy controls as well as between left and right hemisphere damage. Exploratory factor analysis suggested the retention of 25 subtests representing three factors that largely followed the purported structure of the test: Memory and Learning, Language, and Visual-motor Performance. Limitations of the study, clinical/theoretical implications and research directions are considered. It is concluded that the SPANS is a reliable and valid tool for the assessment of cognitive function in people with an acquired brain injury, though further validation studies are required.

The concept of metamemory proposes that supplementary to typically measured memory abilities, memory monitoring and control processes are used to optimise learning. Accurate memory monitoring appears to be underpinned by a range of cognitive, and possibly affective, contributions. In populations with these deficits, metamemory has been shown to be impaired. In Multiple Sclerosis (MS), only a limited metamemory literature exists, surprising given that MS is a leading cause of disability among people of working age, and cognitive and mood disorder is common. Using structural equation modelling, this study of 100 people with MS explored factors contributing to performance on episodic Judgment of Learning, Retrospective Confidence and Feeling of Knowing. Given its negative influence on cognitive domains in MS, the impact of information processing deficits on metamemory was also investigated. Finally, memory self-report, a frequently used clinical indicator of memory functioning, was assessed. Findings suggest that memory complaint is associated with mood, and is unrelated to tested memory. Second, Retrospective Confidence Judgments were predictive of memory performance, even in the presence of memory impairment. Third, an unusual finding of maintained underconfidence at delay was observed in the Judgment of Learning task. Finally, Feeling of Knowing judgments related to executive, but not to memory ability. A novel finding in respect of this judgment was of processing speed relating negatively to accuracy, in the context of executive dysfunction. This suggests that some top-down direction of processing resources may be a factor in supporting accuracy, rather than the speed at which information is processed. Of all the task-based judgments, accuracy in this judgment was the only one with a reliable association with mood. Faster processing speed, executive dysfunction and least depression symptomatology related to low accuracy, perhaps typifying a profile of disinhibition seen in MS, characterised by poorly constrained processing and apparently elevated mood.

Dual-process models propose that two processes support recognition memory; familiarity, a general sense that something has been previously encountered; and recollection, the retrieval of details concerning the context in which a previous encounter occurred. Event-related potential (ERP) studies of recognition memory have identified a set of old/new effects that are thought to reflect these processes: the 300-500ms bilateral-frontal effect, thought to reflect familiarity and the 500-800ms left-parietal effect, thought to reflect recollection. Whilst the exact functional role of these effects remains unclear, they are widely viewed as reliable indices of retrieval. The ERP literature reviewed in this thesis suggests that the characteristics of these recognition effects vary with task specific details and individual participant differences, suggesting that the recognition effects purported to index retrieval may be conditional on both task and participant. This thesis examined the influence of individual differences on behavioural measures of recognition and the neural correlates of recognition memory, focusing on factors of stimulus material, task performance and participant genotype. Clear evidence of stimulus differences were found, with pictures eliciting more anteriorly distributed effects than words, and a late onsetting frontopolar old/new effect that was unique for voices. Furthermore, the pattern of ERP activity associated with successful recognition of faces appeared to vary as a function of general face recognition ability, with participants poorer at remembering faces exhibiting a 300-500ms old/new effect not present for those good at remembering faces. The data also suggested that activity over right-frontal electrodes, evident in some previous studies, may be participant specific and could reflect additional retrieval support processes. Contrary to expectations, behavioural task performance was not found to significantly modulate the ‘typical’ recognition memory effects. However, a number of genetic polymorphisms were found to significantly influence both behavioural scores and the pattern of ERP activity associated with recognition memory. These results therefore suggest that inherent participant differences influence the neural correlates of recognition memory, in a way that variations in task performance do not. Overall, the results from this thesis therefore suggest that the ‘typical’ bilateral-frontal and left-parietal effects thought to index retrieval are not universal. Furthermore the results suggest that the specific processes engaged during retrieval (as indexed by variations in ERP activity) may be dependent on specific task requirements, stimulus material and the genetic makeup of the individual.

Research suggests older adults who remain socially active and cognitively engaged have better cognitive function than older adults who are socially isolated and disengaged. Using an online social networking website, like Facebook.com, may require simultaneous cognitive and social engagement, thus yielding improvements in both domains. This study aimed to examine the efficacy of learning and using Facebook as an intervention to maintain or enhance cognitive function in older adults. Results from a small pilot study with 7 older adults suggested there may be positive effects on executive functions and memory following learning and using Facebook. Therefore, a larger and more well-controlled examination of the intervention was completed. Participants were 41 older adults (12 male), with a mean age of 79.4 and 16.5 mean years of education. Participants were assigned to learn how to use Facebook (n = 14) or an online diary website (active control, n = 13), or they were placed on a waitlist (no treatment control, n = 14). Participants assigned to learn a website attended three 2-hour classes over the course of one week and then used the website at home daily for the next 7 weeks. Participants assigned to the waitlist received no contact for 8 weeks. All participants completed a series of neuropsychological tests and questionnaires on social and lifestyle factors before and after this 8-week period. Results showed that all participants were able to learn and use Facebook or an online diary website over an 8-week period. In addition, the Facebook group showed a significant increase in updating performance at post-test compared to no significant change in the control groups. Other composite measures of executive function, memory, and social support showed no differential improvement in the Facebook group across the 8-week interval. Thus, learning and using an online social networking site appeared to provide specific benefits for executive functions associated with working memory in a group of healthy older adults. This may reflect the particular cognitive demands associated with online social networking and/or the benefits of social engagement more generally.

Following a mild head injury (MHI), a person may report a variety of symptoms such as headache, memory disturbance, dizziness, and concentration difficulties. For most persons the symptoms are transient, but some suffer persistent symptoms that can have a major impact on everyday life. It remains poorly understood why some but not others have full recovery after MHI. The aim of this thesis was to investigate outcomes after MHI, with particular focus on neuropsychological functioning, fatigue, and risk of dementia. A related objective was to examine the potential association of a genetic factor, Apolipoprotein (APOE), with MHI outcome. The APOE є4 allele has been associated with unfavorable outcomes after moderate or severe head injury, but little is known about its influence on outcome after MHI. In Study I and II, data from a population-based longitudinal study were used to compare neuropsychological functioning and fatigue before and after MHI. The results from Study I showed a post-injury decline in neuropsychological performance for є4-carriers, whereas the performance remained unchanged for non-carriers. Study II showed an increase in self-reported fatigue after MHI for both є4-carriers and non-carriers, with a more pronounced increase for є4-carriers. In Study III, a case-control study was conducted to examine whether a history of MHI increased the risk of developing dementia later in life. It was found that MHI alone did not increase the risk, but the combination of MHI and APOE є4 was associated with increased risk of dementia. Taken together, the studies generally indicate a positive outcome after MHI, but in combination with APOE є4 even mild head injury may lead to long-lasting negative outcomes. Consideration of pre-injury level of functioning and genetic factors seems critical for a complete understanding of the impact of MHI.

Hintergrund: Die Neuroborreliose ist eine bei etwa 10-15% der Patienten auftretende Folge der Infektion mit Borrelien. Die typische Klinik im Erwachsenenalter besteht zumeist aus einer polyradikulitischen Symptomatik, die als Bannwarth-Syndrom bezeichnet wird. Dagegen manifestiert sich die Neuroborreliose im Kindes- und Jugendalter meist mit einer monolateralen fazialen Parese oder einer Meningitis. Während im Erwachsenenalter neuropsychologische Langzeitfolgen nach stattgehabter Neuroborreliose anzunehmen sind, ist das mögliche Ausmaß von Langzeitfolgen im Kindes- und Jugendalter bislang noch unklar. Methoden: Das untersuchte Patientenkollektiv bestand aus 29 Patienten, die im Kindes- oder Jugendalter im Zentrum für Kinderheilkunde und Jugendmedizin der Universitätsmedizin Göttingen mit der Diagnose einer Neuroborreliose stationär behandelt wurden. Zum Zeitpunkt der Diagnose betrug das mittlere Alter der Patienten 9,0 ± 2,9 Jahre und es waren durchschnittlich 14,7 ± 3,4 Jahre zwischen Diagnosestellung und Testung vergangen. Das Patientenkollektiv wurde mit einer alters-, bildungs-, und geschlechtsgenormten, gesunden Kontrollgruppe (n=29) verglichen. Die Untersuchung setzte sich aus einer medizinischen Anamnese, einer neurologischen Untersuchung, Fragebögen zur psychiatrischen Beurteilung und einer neuropsychologischen Testbatterie zusammen. Den einzelnen neuropsychologischen Tests wurden Domänen zugeordnet. In der neuropsychologischen Testbatterie wurden die Domänen Aufmerksamkeit, Arbeitsgedächtnis, verbales Lernen und Gedächtnis, non-verbales Lernen und Gedächtnis, visuo-konstruktive Funktionen und frontale Exekutivfunktionen geprüft. Ergebnisse: Die Probanden zeigten signifikant häufiger milde neurologische Einschränkungen. Am Häufigsten fand sich eine residuelle faziale Parese. Hierbei korrelierten die Ergebnisse der neurologischen Untersuchung nicht mit den Ergebnissen der neuropsychologischen Testung. In der neuropsychologischen Testbatterie fanden sich keine signifikanten Unterschiede zur gesunden Kontrollgruppe. Fazit: Im Gegensatz zur durchgemachten Neuroborreliose im Erwachsenenalter, scheint die Erkrankung im Kindes- und Jugendalter nicht mit relevanten neuropsychologischen Langzeitfolgen einherzugehen.

Neuropsychological deficits have been implicated in Chronic Fatigue Syndrome (CFS) and there is some indication that cerebral efficiency is compromised in these patients. To further investigate the nature of this impairment, 20 patients who had received a medical diagnosis of CFS were neuropsychologically assessed and compared with age-, sex-, and education-matched controls (20 depressed and 20 healthy subjects). The test battery consisted of the Grooved Pegboard Trail Making Test, Symbol Digit Modalities Test, Auditory-Verbal Learning Test, Visual Design Learning Test, Controlled Oral Word Association Test and Paced Auditory Serial Addition Task. Additional measures included a CFS symptom checklist, SCL-90-R and Cognitive Failures Questionnaire (CFQ). Univariate statistical analysis revealed a significant difference between CFS patients and healthy individuals on only one measure; the "S" trial of the COWAT (F[2,59]=3.30, p <.05). This finding suggests the existence of subtle but detectable neuropsychological difficulty in executive or attentional mechanisms in CFS patients. Further analysis revealed that the observed finding could not be attributed to depression or medication side-effects. Although a trend of declining neuropsychological test performance was evident in moving across the spectrum of healthy, depressed, and CFS samples, this reached significance only for the CFS/depressed versus healthy comparison X22 [1] = 9.40, p < .05). The overall similarity of the neuropsychological profiles of CFS and depressed patients was noted, while an additional finding was the discrepancy between reported levels of subjective cognitive failure (CFQ) and objective neuropsychological findings in the CFS patients. The SCL-90-R profiles of the CFS and depressed patients were also found to be similar in terms of reported levels of psychological distress; however group discrimination was evident on two subscales (Somatization and Obsessive-Compulsive). Although the CFS and depressed controls did not differ with respect to levels of depression, there were some indications of a differential impact of depressive symptomatology on neuropsychological functioning. Taken together, the results of this study indicate that while subtle deficits are detectable in the neuropsychological profiles of CPS patients, the magnitude of impairment appears insufficient to significantly interfere with everyday cognitive functioning. / Thesis (Ph.D.)-University of Natal, Pietermaritzburg, 1997.

No abstract available. / Thesis (Ph.D.)-University of Natal, Durban, 1989.

Approximately half of Multiple Sclerosis (MS) patients experience cognitive deficits. Accessing neuropsychological assessment can be challenging due to the considerable time, expense, and expertise required for test administration. Computerized cognitive testing has been proposed as an alternative. The objective was to validate a computer generated cognitive screen for MS patients. Ninety-nine MS patients and 98 healthy controls completed the computerized battery consisting of the Stroop, Symbol Digit Modalities Test (C-SDMT), Paced Auditory Serial Addition Test (PVSAT-2, PVSAT-4), and simple and choice reaction time tests. The Minimal Assessment of Cognitive Function in MS (MACFIMS) was used to define cognitive impairment in the MS sample. A combination of the C-SDMT, PVSAT-2, PVSAT-4 had a sensitivity of 83.3% and specificity of 87.7% in detecting cognitive impairment. Each measure had good test-retest reliability (p < 0.001). High sensitivity and specificity, and brevity emphasize the usefulness of the computerized cognitive screen in busy MS clinics.