More often than not learners with learning difficulties are treated differently from normal mainstream learners. Often they experience themselves in a less positive manner because of the interactions with various teachers who may not always have enough patience to deal with these learners while trying to cope with large numbers of learners on a daily base. This study was conducted to explore self-configuration experiences of Intermediate Phase learners with learning difficulties within the learner-teacher relationship. Literature indicates that the self is a complex construct to define and can be interpreted in various ways. The researcher aimed to understand how the self is configured in experiences that learners have with their teachers and how these experiences contribute to and affect self-configuration. The theoretical frameworks of the Dialogical Theory of Self and the Gestalt Field Theory were used to gain an understanding of how vital relations and context are in the configuration experiences of the self. A qualitative case study with purposive sampling was conducted. The study was done at a single school where all the learners in the school have learning difficulties. There were nine learners that fell in the Intermediate Phase category and all of them were boys who voluntarily participated in the research. Data were collected by means of a semi-structured interview in which the participants were asked to use incomplete sentences and a visual map that they made to help them express their experiences. A follow-up interview was conducted to check that the meaning that the learner ascribed to his incomplete sentences and visual map was accurate and an opportunity was given to add something should the participant want to. Participants were given this opportunity as some of them had difficulty in expressing themselves adequately during the first session as a result of their learning difficulties in so much as they struggle to find words that express their feelings and what they wanted to communicate. Data were transcribed and analysed by means of thematic analysis. The study indicated that it was aspects such as quality time the teachers spent with the learners and the tone of voice of the teacher that contributed to the self-configuration experiences of the learners. Further research is necessary to determine whether this is the experience in other schools that cater for learners with learning difficulties and how this knowledge may be used to bring greater awareness to teachers to better understand how learners experience their relationship with regards to self-configuration. Quantitative studies can also be conducted to investigate the impact of teacher-learner relationships on self-configuration. / MA (Psychology), North-West University, Potchefstroom Campus, 2015

Approximately forty percent of youths’ waking hours are unrestricted and not committed to activities such as eating, sleeping or going to school. Many of this free time is spent without companionship or supervision from adults, which puts them at risk of spending their time out on the streets, where the risk of succumbing to peer pressure and becoming involved in inappropriate or illegal activities is increased. The absence of structured activities, stimulation and support can lead to youth becoming involved in rebellious and unwanted behaviour, partly due to their continuous search for adventure and excitement. Learners with Mentally Mild Learning Disabilities (MMLD) can be seen as youth at risk because of their academic and behavioural problems. Learning disabilities can increase the risk factors for delinquency and substance dependence. Previous research suggests that adventure-based experiential programmes (AEPs), which are highly structured, can thus be a very powerful intervention or prevention medium to empower youth at risk to overcome obstacles through the acquisition and practise of skills. The purpose of the study was firstly to determine what the personal functioning profile of MMLD youth looks like, which was done in order to gain insight into the different aspects of the personal functioning, which were focused on when developing the AEP. The study was secondly done to determine what the role of an AEP is on the personal functioning of learners with MMLD. Books, journals, dissertations, theses and internet sources were used to do a thorough literature review. The literature review was done in order for readers to understand the link between MMLD youth and an AEP. The literature review gave an introduction to the phenomenon of MMLD youth and also explained how an AEP could be beneficial towards them. A qualitative research design was used by the researcher in the form of an instrumental case study. Case studies make it possible for the researcher to use qualitative as well as quantitative constructs for data gathering purposes. Sampling of participants was done in two steps. A school for Learners with Special Education Needs (LSEN) (Die Wilge High School) was sampled through purposeful sampling by means of criterion-based sampling techniques. The second step was to sample fourteen male learners from Die Wilge High School through purposive sampling. The personal functioning was determined by using the Youth at Risk Assessment Scale (YAR3) Questionnaire 3. The researcher made use of semi-structured, one-on-one interviews and field notes in order to gather data. The field notes and transcribed interviews were analysed in order to obtain a clear picture of the content, which was then used to identify the codes. After the data was analysed four main themes, each with its own categories, were identified. The themes related to the personal functioning of the youth and consisted of interpersonal relationships, trust, self-worth and perseverance. The learners had positive feedback regarding their interpersonal relationships, trust, self-worth and perseverance before participation in the AEP. This was attributed to the Strengths-based Approach which the researcher followed in the development of the AEP. Despite this positive feedback, the learners still felt that there was an improvement after the AEP in all of the areas. Most of the learners attributed the improvement to learning more about each other, learning to work together and building friendships among each other. These new found friendships made it easier to trust each other and believe in themselves. The learners also realised that they experienced more positive feelings from persevering than when they quit. The results were used to discuss the objective of the study and to determine if the researcher met the objective. / MA (Recreational Science), North-West University, Potchefstroom Campus, 2015

More often than not learners with learning difficulties are treated differently from normal mainstream learners. Often they experience themselves in a less positive manner because of the interactions with various teachers who may not always have enough patience to deal with these learners while trying to cope with large numbers of learners on a daily base. This study was conducted to explore self-configuration experiences of Intermediate Phase learners with learning difficulties within the learner-teacher relationship. Literature indicates that the self is a complex construct to define and can be interpreted in various ways. The researcher aimed to understand how the self is configured in experiences that learners have with their teachers and how these experiences contribute to and affect self-configuration. The theoretical frameworks of the Dialogical Theory of Self and the Gestalt Field Theory were used to gain an understanding of how vital relations and context are in the configuration experiences of the self. A qualitative case study with purposive sampling was conducted. The study was done at a single school where all the learners in the school have learning difficulties. There were nine learners that fell in the Intermediate Phase category and all of them were boys who voluntarily participated in the research. Data were collected by means of a semi-structured interview in which the participants were asked to use incomplete sentences and a visual map that they made to help them express their experiences. A follow-up interview was conducted to check that the meaning that the learner ascribed to his incomplete sentences and visual map was accurate and an opportunity was given to add something should the participant want to. Participants were given this opportunity as some of them had difficulty in expressing themselves adequately during the first session as a result of their learning difficulties in so much as they struggle to find words that express their feelings and what they wanted to communicate. Data were transcribed and analysed by means of thematic analysis. The study indicated that it was aspects such as quality time the teachers spent with the learners and the tone of voice of the teacher that contributed to the self-configuration experiences of the learners. Further research is necessary to determine whether this is the experience in other schools that cater for learners with learning difficulties and how this knowledge may be used to bring greater awareness to teachers to better understand how learners experience their relationship with regards to self-configuration. Quantitative studies can also be conducted to investigate the impact of teacher-learner relationships on self-configuration. / MA (Psychology), North-West University, Potchefstroom Campus, 2015

The overall aim was to improve knowledge of the consequences of cognitive dysfunction in everyday life and of instruments to make these assessments. The thesis contains four studies each of different design using different populations. In study I, the relationship between cognitive function, ability to perform activities of daily living and perceived health-related quality of life were investigated in a population of 85-year-old individuals in the community of Linköping (n = 373). The study was part of the Elderly in Linköping Screening Assessment 85 (ELSA 85). Even mild cognitive dysfunction correlated with impaired ability to perform activities of daily living and lower health-related quality of life. In study II, the diagnostic accuracy and clinical utility of Cognistat, a cognitive screening instrument, were evaluated for identifying individuals with cognitive impairment in a primary care population. Cognistat has relatively good diagnostic accuracy with a sensitivity of 0.85, a specificity of 0.79 and a Clinical Utility Index (CUI) of 0.72. The corresponding values were 0.59, 0.91 and 0.53 for the Mini Mental State Examination (MMSE), and 0.26, 0.88 and 0.20 for the Clock Drawing Test (CDT). In study III, the aim was to develop an instrument measuring self-perceived or caregiver reported ability to perform everyday life activities in persons with suspected cognitive impairment or dementia and to perform psychometric testing of this instrument, named the Cognitive Impairment in Daily Life (CID). The CID was found to have good content validity. In study IV, experiences of cognitive impairment, its consequences in everyday life and the need for support in persons with mild cognitive impairment (MCI) or mild dementia and their relatives were explored. Interviews were performed with five people with MCI, eight people with mild dementia and their relatives (n = 13). The main finding was that persons with MCI and dementia experienced cognitive changes that could be burdensome and result in changed activity patterns. In conclusion, the findings support earlier research and show that cognitive dysfunction even at mild stages has an impact on everyday life and reduces perceived quality of life. To improve interventions for persons with cognitive impairment, it is important to assess not only cognitive function but also its consequences in everyday life activities.

Introduction: Dementia is a syndrome due to disease of the brain, usually of a chronic nature, in which there is disturbance of multiple higher cortical functions including Memory, Comprehension, Thinking, Judgment, Orientation, language and communication skills and abstract thinking. It is one of the most challenging disorders both in terms of prevalence and economic burden. There are currently approximately 800,000 people with dementia in UK and national cost is 17 billion per year. It is estimated that in next thirty years, number of people with dementia will increase to 1.4 million and the national cost will be over 50 billion. The exceptional advances in modern medicine in terms of prolonging life expectancy do not necessarily improve the care delivered to people with dementia. Dementia is a progressive condition where clinical recovery is not possible despite the discovery of cognition enhancing drugs. This belief leads to low expectations that tend to erode hope and foster indignity. Advances in treatment of Alzheimer’s disease have, however, stimulated new thinking and methods of service delivery. At certain stage of their illness, if not from the very beginning, personal, and social recovery becomes more meaningful for service users than their clinical recovery. Objective: To investigate whether recovery-orientated psychiatric assessment and therapeutic intervention enhances the wellbeing of people with memory problems and their family carers. Method: This study was a preliminary randomised control study. Patients were randomly allocated to recovery focus group or treatment as usual group acting as the control. Participants in the recovery focus group received a recovery-focused pre-diagnostic wellbeing assessment and counselling, diagnostic consultation with written feedback and post-diagnostic support over a period of six months. Participants in both groups were assessed using the WHO Wellbeing Index (WHO-5) as the primary outcome measure. The Mini Mental State Examination, Cornell Scale for Depression in Dementia, EuroQol-5D and Zarit Burden Interview were used as secondary outcome measures. Written records of the narrative accounts of participants in the recovery focus group were also obtained. Results: 48 patients with early dementia were recruited and agreed to take part in the study. Out of these, 34 patients completed the study, of which 17 patients were in the recovery focus group and 17 patients were in the treatment as usual group (control).There was a significant difference between the groups in terms of greater improvement in wellbeing as rated by the WHO – 5 Wellbeing Index in the recovery focus group compared to the control group. The secondary outcome measures in the areas of cognition, quality of life and caregiver burden showed no differences between the groups. However, case histories from the recovery focus group identified the main areas of improvement in improved mood, increased social interaction, reduction in carer strain and/or burden and improved self-worth and/or confidence. Conclusions: This study shows that recovery focused care can enhance the wellbeing of people with mild to moderate dementia. The additional benefits perceived by the patients and their relatives /carers include improvement in mood symptoms, social interaction and confidence as well as reduction in carer burden and strain.

<p>Use of chemotherapeutics in treatment of solid tumors suffers from insufficient and heterogeneous drug delivery, systemic toxicity and lack of knowledge of delivered drug concentration. The overall objectives of this work were: 1) to address these shortcomings through development and characterization of a treatment system capable of real-time spatiotemporal control of drug distribution and 2) to investigate the role of MR-image-able tissue transport parameters in predicting drug distribution following hyperthermia-triggered drug release from nanoparticles. Towards these objectives, a combination of potentially synergetic technologies was used: 1) image-able low temperature-sensitive liposomes (iLTSLs) for drug delivery, 2) quantitative drug delivery and transport parameter imaging with magnetic resonance imaging (MRI), and 3) control over drug release with magnetic resonance-guided high intensity focused ultrasound (MR-HIFU). The overall hypothesis of this work is that the drug distribution in the targeted zone spatially correlates with the image-able transport-related parameters as well as contrast enhancement due to release of contrast agent during treatment.</p><p>We began by developing and characterizing iLTSLs, which were designed using a lipid formulation similar to one that is in clinical trials in the US (ThermoDox®) and a gadolinium-based MR contrast agent that is in widespread clinical use (Prohance®) and least likelihood of toxicity due to nephrogenic systemic fibrosis (NSF). The resulting liposome was found to stably encapsulate both an anthracycline chemotherapeutic, doxorubicin, and the MR contrast agent. Release rates were similar for these two species in physiologic buffer as well as in human plasma. The next step towards control and imaging of release with this drug delivery system (DDS) was development of algorithms that allowed for large-volume mild hyperthermia with MR-HIFU that would be required to move this combination of technologies into the clinic.</p><p>Optimal drug delivery with iLTSL requires a sustained period of heating of the entire target to the range of temperatures that are optimal for liposomal release and maintenance of perfusion (40 - 45 &#61616;C). The MR-HIFU technology was developed and used mainly for rapid thermal ablation or mechanical disruption of tissue in small ellipsoid volumes. Variability and size of common clinical lesions called for modifications that would enable stable conformal heating of large tumor volumes to the sub-ablative temperature range of mild hyperthermia (40 - 45 &#61616;C). Therefore, we set out to develop an algorithm that would allow rapid attainment and maintenance of mild hyperthermia in larger volumes of variable shape that were typically encountered in the clinic. We approached this goal through a series of successive steps that addressed different aspects of mild hyperthermia treatment: 1) controlled heating to mild hyperthermia, 2) conformity of heating and 3) ability to heat large volumes.</p><p>To achieve controlled heating to mild hyperthermia we implemented a simple binary mild hyperthermia feedback mechanism that adequately maintained mild hyperthermia for extended periods of time in small ellipsoidal volumes. We then developed a conformal small-volume mild hyperthermia algorithm that could provide spatial control over heating in an environment with spatially heterogeneous perfusion. This algorithm used electronic steering of the HIFU focus to heat each MR image voxel with different power, depending on temperature measured within that voxel. Finally, to heat large volumes conformally, we developed an algorithm that combined mechanical displacement of the MR-HIFU transducer (to cover large areas) with electronic deflection of the HIFU beam (to heat sub-volumes conformally). This advancement allowed us to quickly attain mild hyperthermia (<8.1 min to steady state) in larger volumes (cross-sectional area = 8.4 cm, ~12 times larger than previous methods).</p><p>Following their characterization, we examined iLTSL pharmacokinetics and combined MR-HIFU large volume mild hyperthermia with iLTSL to deliver doxorubicin to large Vx2 carcinomas in the hindlimb muscle of rabbits. To determine MR image-able correlates to the intratumoral drug distribution, we assessed the spatial pattern of drug distribution with fluorescence microscopy and examined spatial correlations of this pattern to several parameters measured with MRI, including the spatial distributions of temperature, contrast enhancement following injection of iLTSL, dynamic contrast-enhanced MRI (DCE-MRI) parameters, and maps of apparent diffusion coefficient (ADC). Dynamic contrast-enhanced MRI parameters have been used extensively in literature to approximate a mixture of parameters critical to drug delivery, such as perfusion (F), permeability-vascular surface area product (PS) and vascular volume and ADC has been previously correlated with cellular density in tumors. Possible utility of such spatial correlations was examined for future use in treatment planning, intraprocedural feedback control and post-treatment evaluation.</p><p>Highly perfused peripheral regions of Vx2 tumors in rabbit hindlimb displayed high Ktrans and ve, indicative of high perfusion. Maps of ADC obtained with low b-values also showed high ADC in the periphery of these tumors, indicating high perfusion there. ADC maps that were weighted more towards diffusion (using higher b-values) showed that diffusion was largest in the tumor core, indicating destruction of the cellular membranes and greater mobility of water. Microscopic examination of excised tumors was spatially registered to the MRI datasets and showed that most of the tumor core is necrotic, though some highly vascularized and viable tissue was present in strands or segments that traversed the necrotic regions. Those segments also showed bright doxorubicin fluorescence following treatment with MR-HIFU and iLTSL. The two control groups - free drug and iLTSL without mild hyperthermia - showed minimal to no doxorubicin fluorescence in the tumor.</p><p>Susceptibility effects due to use of contrast agent caused large errors (up to 15 °C) in MR thermometry measurements. To address this phenomenon, experiments were designed to arrive at steady state heating (target temperature = 41 °C), and employ an algorithm to learn the spatiotemporal distribution of power that was needed to maintain steady state heating. This heating pattern was then played back several times to verify maintenance of steady state, and if satisfactory, image-able liposomes were injected. Since temperature feedback was replaced by the learned steady-state heating, injection of image-able liposomes likely did not alter the heating performance. Following injection, changes in T1 and magnetic susceptibility were most pronounced in regions that previously showed greatest enhancement during DCE-MRI and displayed larger values of ADC with perfusion-weighted, low b-value scans. Maps of T1 were obtained in real time using a variable flip angle sequence during heating, and were corrected for inhomogeneity of the B1 field and calibrated against a more accurate, T1 mapping technique.</p><p>After treatment with MR-HIFU and iLTSL, the drug was preferentially distributed in the viable tissue, in and around the tumor. Doxorubicin fluorescence was greatest in zones that were heated, though the drug distribution did not display a clear boundary between heated and unheated tissue. While iLTSL provided intraprocedural feedback via enhancement of T1-weighted image intensity, susceptibility-related effects of iLTSL on MR thermometry complicate their prospects of clinical use, where precise temperature feedback is required for control of therapy and MR thermometry techniques that are in widespread use would be affected. Spatial correlations between drug delivery with iLTSL and MR-imageable parameters may serve as a predictive tool to identify areas that will not receive adequate drug. Such a-priori knowledge of correlates to the approximate tumor drug distribution has the potential to inform treatment planning by revealing the extent to which drug dose could be painted with a combination of LTSL and MR-HIFU. These studies point to an adjustment of course in further development of drug dose painting this combination of technologies, towards informing treatment planning, and not only painting the dose, but predicting it. These results also point to the need to develop rational combinations other treatments, such as ablation and radiation, to treat regions that will not receive sufficient drug.</p> / Dissertation

This thesis reports on the research outcome of corrosion mechanism and corrosion rate of mild steel in different environments (saline, alkaline solutions and concrete media) using potentiodynamic polarization technique. The study also included the effect of corrosion on bond strength between reinforcing steel and concrete using pull-out test. Corrosion of mild steel and 316L stainless steel with different surface conditions in 1, 3 and 5% saline (NaCl + Distilled water) was investigated. Specimens ground with 200 and 600 grit silicon carbide grinding paper as well as 1μm surface finish (polished with 1μm diamond paste) were tested. In case of mild steel specimens, reduction in surface roughness caused increase in corrosion rate, while in 316L stainless steel corrosion rate decreased as the surface roughness improved. Metallographic examination of corroded specimens confirmed breakdown of passive region due to pitting corrosion. Corrosion of mild steel was also investigated in alkaline solution (saturated calcium hydroxide, pH =12.5) contaminated with 1, 3 and 5% saline. A series of corrosion experiments were also conducted to examine the efficiency of various concentrations of calcium nitrite (CN) on corrosion behaviour of both as-received and polished mild steel in alkaline solution containing 3% saline after 1 hour and 28 days of exposure. Corrosion rate was higher for the as-received than polished mild steel surface under the same testing conditions in NaCl alkaline solution with and without nitrites due to the effect of surface roughness. Morphology investigation of mild steel specimens in alkaline solution ii containing chlorides and nitrites showed localized pits even at nitrite concentration equal to chloride concentration. Corrosion of steel bars embedded in concrete having compressive strengths of 20, 30 and 46MPa was also investigated. The effect of 2 and 4% CN by weight of cement on corrosion behaviour of steel bar in low and high concrete strengths specimens were also studied. All reinforced concrete specimens were immersed in 3% saline solution for three different periods of 1, 7 and 15 days. In order to accelerate the chemical reactions, an external current of 0.4A was applied. Corrosion rate was measured by retrieving electrochemical information from polarization tests. Pull-out tests of reinforced concrete specimens were then conducted to assess the corroded steel/concrete bond characteristics. Experimental results showed that corrosion rate of steel bars and bond strength were dependent on concrete strength, amount of CN and acceleration corrosion period. As concrete strength increased from 20 to 46MPa, corrosion rate of embedded steel decreased. First day of corrosion acceleration showed a slight increase in steel/concrete bond strength, whereas severe corrosion due to 7 and 15 days corrosion acceleration significantly reduced steel/concrete bond strength. Addition of only 2% CN did not give corrosion protection for steel reinforcement in concrete with 20MPa strength at long time of exposure. However, the combination of good quality concrete and addition of CN appear to be a desirable approach to reduce the effect of chloride induced corrosion of steel reinforcement. At less time of exposure, specimens without CN showed higher bond strength in both concrete mixes than those with CN. After 7 days of corrosion acceleration, the higher concentration of CN gave higher bond strength in both concrete mixes. The same trend was observed at 15 days of corrosion acceleration except for the specimen with 20MPa compressive strength and 2% CN which recorded the highest deterioration in bond strength.

Alzheimer's disease (AD) is a progressive, irreversible, neurodegenerative disease. The key to understanding AD is to elucidate the pathogenesis of neuron degeneration in specific brain regions.We hypothesize that there is increased DNA oxidation in AD brain compared to age-matched control subjects, especially in mitochondrial DNA (mtDNA), and that the changes in DNA bases will affect protein expression in mitochondria and contribute to neurodegeneration in AD. To test this hypothesis:1) We quantified multiple oxidized bases in nuclear DNA (nDNA) and mtDNA of frontal, parietal, and temporal lobes and cerebellum from late-stage AD (LAD), mild cognitive impairment (MCI), and age-matched control subjects using gas chromatography/mass spectrometry with selective ion monitoring (GC/MS-SIM). Also, we quantified oxidized DNA bases in cortex of APP/PS1 transgenic mice. (a) nDNA and mtDNA were extracted from eight LAD and eight control subjects. We found levels of multiple oxidized bases were significantly higher in frontal, parietal, and temporal lobes and that mtDNA had approximately 10-fold higher levels of oxidized bases than nDNA. Eight-hydroxyguanine was approximately 10-fold higher than other oxidized base adducts in both LAD and control subjects. These results suggest that oxidative damage to mtDNA may contribute to the neurodegeneration of AD. (b) Mild Cognitive Impairment (MCI), the phase between normal aging and early dementia, is a common problem in the elderly with many subjects going on to develop AD. Results from eight amnestic MCI and six control subjects suggest oxidative damage to DNA occurs in the earliest detectable phase of AD. (c) Analysis of nDNA from the cortex of four groups (3m, 6m, 9m, 12m) of APP/PS1 and wild type mice showed elevations of 8-hydroxyguanine in 12 month old APP/PS1 mice.2) To analyze mitochondrial protein changes in LAD, 2D gels were run to separate proteins and MALDI-TOF mass spectrometry was used to identify proteins.Five mitochondrial proteins were significantly decreased in LAD. This proteomic study provides a proteome map of mitochondria in LAD brain and an insight into the pathogenesis of neuron degeneration in Alzheimer's disease.

Dementia is increasingly recognized as a major and growing threat to public health worldwide, and there is a critical need for prevention and treatment strategies. However, it is necessary that appropriate methodologies are used in the identification of risk factors. The purpose of this dissertation research was to develop further the body of literature featuring Markov chains as an analytic tool for data derived from longitudinal studies of aging and dementia. Data drawn from 649 participants in the University of Kentucky’s Alzheimer’s Disease Center’s (UK ADC) Biologically Resilient Adults in Neurological Studies (BRAiNS) cohort, which was established in 1989 and follows adults age 60 years and older who are cognitively normal at baseline to death, were used to conduct three studies. The first study, “Mild cognitive impairment: Statistical models of transition using longitudinal clinical data,” shows that mild cognitive impairment is a stable clinical entity when a rigorous definition is applied. The second study, “Self-reported head injury and risk of cognitive impairment and Alzheimer’s-type pathology in a longitudinal study of aging and dementia,” shows that when the competing risk of death is properly accounted for, self-reported head injury is a clear risk factor for late-life dementia and is associated with increased beta-amyloid deposition in the brain. The third study, “Incorporating prior-state dependence among random effects and beta coefficients improves multistate Markov chain model fit,” shows that the effect of risk factors, like age, may not be constant over time and may be altered based on the subject’s cognitive state and that model fit is significantly improved when this is taken into account.

Background and aims: The provenance of post-concussion symptoms (PCS) and post-traumatic stress (PTSD) after mild traumatic brain injury (mTBI) is controversial. This thesis investigated factors influencing these two conditions separately, as well as the interplay between PCS and PTSD, in individuals with mTBI and a control sample without mTBI (orthopaedic injuries). Method: Consecutive adult attendees of an Emergency Department with mTBI or orthopaedic injury were prospectively recruited and completed the Rivermead Post-concussion Questionnaire (RPQ) and Trauma Screening Questionnaire (TSQ) for PTSD at two weeks (T1) and three months (T2) post-injury. The sample at T1 consisted of 34 with complicated mTBI, 76 with uncomplicated mTBI and 47 with orthopaedic injury, and 18 with complicated mTBI, 43 with uncomplicated mTBI and 33 orthopaedic controls at T2. Results: Although there were no differences in overall PCS symptomology between groups, a subset of PCS symptoms (headaches, dizziness and nausea) was found to be specific to mTBI at both time points. These symptoms are proposed to have a neurological basis, as opposed to a psychological basis. PTSD interacted with PCS, particularly in mTBI, such that PTSD was associated with greater “neurogenic” and “psychogenic” symptomology in this group, but only a moderate increase in psychogenic symptoms for controls. A model of the influence of PTSD on PCS is presented. PTSD was influenced by poor memory quality for the traumatic event and attribution of blame to others, but not by mTBI. Discussion and conclusions: Though mTBI may set the scene for at least neurogenic symptoms of PCS to occur, psychological mechanisms, particularly PTSD, have a significant role in the persistence of PCS. Our findings suggest the need for a clear story and sense of meaning for a traumatic event for good recovery from PTSD. Taken together, the results suggest that psychological interventions, particularly aimed at PTSD, may be most effective after mTBI.