RESUMO
Traumatic events can be associated with positive change, termed "post-traumatic growth." Existing resesarch suggests some overlap between post-traumatic growth and value-directed living. This study sought to explore the relationship between post-traumatic growth and value-directed living after acquired brain injury. Self-report questionnaires including the Posttraumatic Growth Inventory, Valued Living Questionnaire, Engaged Living Scale, Valuing Questionnaire, Hospital Anxiety and Depression Scale, World Health Organization Well-Being Index, Brief Resilience Scale, Trauma Screening Questionnaire and Glasgow Outcome Scale were posted to 317 individuals who had experienced a head injury, stroke or subarachnoid haemorrhage in the previous 3-13 years, with a hospital admission of minimum 7 days. Questionnaires were completed by 81 participants. Post-traumatic growth was significantly positively associated with two measures of value-directed living (VLQ, r = .269; VQ, r = .215). Higher levels of value-directed living were significantly associated with increased positive outcomes (wellbeing) and reduced negative outcomes (distress, post-traumatic stress symptoms). There was no significant association between post-traumatic growth and any of these outcomes. The association between post-traumatic growth and value-directed living indicates possible common underlying processes. Value-directed living appears to be a more useful concept, as it was associated with clinically relevant outcomes. It is recommended that value-directed living interventions are considered in brain injury rehabilitation.
Assuntos
Lesões Encefálicas Traumáticas , Lesões Encefálicas , Crescimento Psicológico Pós-Traumático , Lesões Encefálicas/complicações , Lesões Encefálicas Traumáticas/complicações , Humanos , Inquéritos e QuestionáriosRESUMO
Considerable research has demonstrated that workplace rudeness can have a variety of negative consequences. However, although research has examined the impact of patient aggression, no research has examined patient or client rudeness towards those who work in mental health roles. The present study investigated the nature of client rudeness, how mental health workers respond and the coping strategies used. Eighteen participants from a range of mental health roles and experience levels participated in semi-structured interviews based on their experience of client rudeness. Thematic analysis revealed that participants experienced a variety of client behaviours they classified as rude, the majority of which were verbal. Reasons for rudeness included the client's personal history, mood, and mental health, and as such rudeness was conceptualised as simply a part of the job. Client rudeness was found to have both negative and positive outcomes on a range of areas including work and client relationships. Participants identified supervisors and colleagues as key sources of support for coping with rudeness. These findings suggest that rudeness is "part and parcel" of a mental health practitioner's role. Supervisor support and further training are recommended to help practitioners deal with rudeness in practice.
Assuntos
Adaptação Psicológica , Incivilidade , Relações Enfermeiro-Paciente , Enfermagem Psiquiátrica , Atitude do Pessoal de Saúde , Feminino , Humanos , Masculino , Pesquisa Qualitativa , Reino UnidoRESUMO
Significantly above-chance detection of stimuli presented within the field defect of patients with postgeniculate lesions is termed "blindsight." It has been proposed that those with blindsight are more likely to benefit from visual rehabilitation by repeated stimulation, leading to increased visual sensitivity within their field defect. Establishing the incidence of blindsight and developing an objective and reliable method for its detection are of great interest. Sudden onsets of a grating pattern in the absence of any change in light flux result in a transient constriction of the pupil, termed "pupil grating response." The existence of pupil grating responses for stimuli presented within the blindfield has previously been reported in a hemianopic patient and two monkeys with removal of the primary visual cortex unilaterally. Here, we have systematically investigated the presence of a spatial channel of processing at a range of spatial frequencies using a psychophysical forced-choice technique and obtained the corresponding pupil responses in the blindfield of 19 hemianopic patients. In addition, in 13 cases we determined the pupil responses in a sighted field location that matched the blindfield eccentricities. Our findings demonstrate that blindfield pupil responses are similar to those for the sighted field, but attenuated in amplitude. Pupillometry correctly characterized the presence or absence of a significant psychophysical response and thus is worth measuring in the cortically blindfields as a predictor of intact psychophysical capacity. The incidence of blindsight where detection performance had been investigated psychophysically over a range of spatial frequencies was 70%.
Assuntos
Hemianopsia/fisiopatologia , Pupila/fisiologia , Visão Ocular/fisiologia , Humanos , Estimulação Luminosa , Psicofísica , EscóciaRESUMO
PURPOSE: We investigated systematically the effect of repeated exposure on detection and reported awareness of visual stimuli presented deep within the field defect of 5 hemianopic patients. METHODS: An objective measure of sensitivity (detection in a temporal two-alternative forced-choice paradigm) and subjective reports of awareness were recorded on trial by trial bases. Visual stimulus to be detected was a temporally modulated (10 Hz) circular patch (6° diameter) of vertical grating (1 c/°). Hemianopic patients took part in the study 8 to 15 months after injury, so that the findings could not be attributed to spontaneous recovery. RESULTS: Initially, high contrast (90%) target stimuli were detected at or near chance level with little reported awareness. In 4 of 5 cases, repeated stimulation led to improved sensitivity, indicated by increased detection scores and higher incidence of awareness. In a fifth case, there was no change in sensitivity despite extensive exposure (>22,000 trials). CONCLUSIONS: At retinal locations deep within the field defect, repeated stimulation can lead to blindsight performance (type I detection without awareness), followed by detection with reported awareness (type II blindsight), and eventual reported visual experiences. The findings indicate that conscious awareness of stimuli lies on a continuous spectrum and repeated systematic training can lead to improved visual sensitivity.
Assuntos
Conscientização/fisiologia , Cegueira/fisiopatologia , Cegueira/reabilitação , Hemianopsia/fisiopatologia , Hemianopsia/reabilitação , Percepção Visual/fisiologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estimulação Luminosa/métodos , Acidente Vascular Cerebral/fisiopatologia , Córtex Visual/fisiologia , Córtex Visual/fisiopatologia , Campos Visuais/fisiologiaRESUMO
Lesions of occipital cortex result in loss of sight in the corresponding regions of visual fields. The traditional view that, apart from some spontaneous recovery in the acute phase, field defects remain permanently and irreversibly blind, has been challenged. In patients with partial field loss, a range of residual visual abilities in the absence of conscious perception (blindsight) has been demonstrated (Weiskrantz, 1986). Recent findings (Sahraie et al., 2006, 2010) have also demonstrated increased visual sensitivity in the field defect following repeated stimulation. We aimed to extend these findings by systematically exploring whether repeated stimulation can also lead to increased visual sensitivity in two cases with total (bilateral) cortical blindness. In addition, for a case of partial blindness, we examined the extent of the recovery as a function of stimulated region of the visual field, over extended periods of visual training. Positive auditory feedback was provided during the training task for correct detection of a spatial grating pattern presented at specific retinotopic locations using a temporal two alternative forced-choice paradigm (Neuro-Eye Therapy). All three cases showed improved visual sensitivity with repeated stimulation. The findings indicate that perceptual learning can occur through systematic visual field stimulation even in cases of bilateral cortical blindness.
RESUMO
At suprathreshold levels, detection and awareness of visual stimuli are typically synonymous in nonclinical populations. But following postgeniculate lesions, some patients may perform above chance in forced-choice detection paradigms, while reporting not to see the visual events presented within their blind field. This phenomenon, termed "blindsight," is intriguing because it demonstrates a dissociation between detection and perception. It is possible, however, for a blindsight patient to have some "feeling" of the occurrence of an event without seeing per se. This is termed blindsight type II to distinguish it from the type I, defined as discrimination capability in the total absence of any acknowledged awareness. Here we report on a well-studied patient, D.B., whose blindsight capabilities have been previously documented. We have found that D.B. is capable of detecting visual patterns defined by changes in luminance (first-order gratings) and those defined by contrast modulation of textured patterns (textured gratings; second-order stimuli) while being aware of the former but reporting no awareness of the latter. We have systematically investigated the parameters that could lead to visual awareness of the patterns and show that mechanisms underlying the subjective reports of visual awareness rely primarily on low spatial frequency, first-order spatial components of the image.
Assuntos
Estado de Consciência , Percepção Visual , Conscientização , Humanos , Reconhecimento Visual de Modelos , Estimulação Luminosa , Campos VisuaisRESUMO
Damage to the optic radiation or the occipital cortex results in loss of vision in the contralateral visual field, termed partial cortical blindness or hemianopia. Previously, we have demonstrated that stimulation in the field defect using visual stimuli with optimal properties for blindsight detection can lead to increases in visual sensitivity within the blind field of a group of patients. The present study was aimed to extend the previous work by investigating the effect of positive feedback on recovery of visual sensitivity. Patients' abilities for detection of a range of spatial frequencies within their field defect were determined using a temporal two-alternative forced-choice technique, before and after a period of visual training (n = 4). Patients underwent Neuro-Eye Therapy which involved detection of temporally modulated spatial grating patches at specific retinal locations within their field defect. Three patients showed improved detection ability following visual training. Based on our previous studies, we had hypothesised that should the occipital brain lesion extend anteriorly to the thalamus, little recovery would be expected. Here, we describe one such case who showed no improvements after extensive training. The present study provides further evidence that recovery (a) can be gradual and may require a large number of training sessions (b) can be accelerated using positive feedback and (c) may be less likely to take place if the occipital damage extends anteriorly to the thalamus.
Assuntos
Lesões Encefálicas/patologia , Lesões Encefálicas/reabilitação , Corpos Geniculados/fisiopatologia , Modalidades de Fisioterapia , Adulto , Cegueira/etiologia , Cegueira/fisiopatologia , Cegueira/reabilitação , Lesões Encefálicas/fisiopatologia , Feminino , Lateralidade Funcional/fisiologia , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Estimulação Luminosa/métodos , Psicofísica/métodos , Tomografia Computadorizada por Raios X/métodos , Córtex Visual/patologia , Campos Visuais/fisiologia , Adulto JovemRESUMO
Residual sensorimotor skills which survive compromise of the geniculostriate visual system may depend on activity of the dorsal stream of extrastriate occipitoparietal cortex. These circuits are crucial for controlling hand and eye movements to targets in a three-dimensional world. Remarkably, demonstrations of above chance localisation by hand and by eye in blindsight patients have used luminous targets that were only varied in one spatial dimension. These limitations result in experimental confounds. In the present study we examined saccadic and manual localisation in a well-studied patient (DB) to positions that were varied in 1 or 2 dimensions, using targets which control for luminance artefacts. We found that his good manual localisation without awareness in 1D conditions was relatively preserved when the targets were varied in 2D. In stark contrast, saccadic performance was completely attenuated with 2D targets. These paradoxical results are difficult to reconcile with feedforward models of eye-hand coordination and with accounts of localisation that depend on intact multidimensional representations of the visual fields in non-geniculostriate systems.
Assuntos
Cegueira Cortical/fisiopatologia , Percepção de Forma/fisiologia , Desempenho Psicomotor , Movimentos Sacádicos/fisiologia , Visão Ocular/fisiologia , Idoso , Estudos de Casos e Controles , Humanos , Masculino , Pessoa de Meia-Idade , Estimulação Luminosa/métodos , Tato/fisiologia , Campos Visuais/fisiologiaRESUMO
The term blindsight, coined by Larry Weiskrantz, describes those discrimination abilities that can be elicited with visual stimuli restricted to the blindfield of a patient with occipital brain lesion or damaged optic radiation. Over the past 3 decades, many aspects of blindsight have been investigated including detection of basic stimulus attributes such as structure, colour and movement as well as more complex tasks such as discrimination of facial expressions and semantic processing. The neuronal mechanisms mediating blindsight rely on processing in subcortical and/or extrastriate areas. It appears that following the occipital brain damage, there is a restricted "window of processing" and stimulus parameters mainly outside this window may not lead to blindsight performance. Here we report how the restricted "window of processing" appears to have a specific spatio-temporal response profile, mainly tuned to low spatial frequencies and intermediate temporal frequencies. In addition, in a group of blindsight patients, we demonstrate that above chance detection performance is related to the target size. The findings have implications both for the reported incidence of blindsight and development of rehabilitation strategies.
Assuntos
Mapeamento Encefálico , Discriminação Psicológica/fisiologia , Hemianopsia/patologia , Percepção Espacial/fisiologia , Córtex Visual/fisiopatologia , Campos Visuais/fisiologia , Adulto , Idoso , Comportamento de Escolha/fisiologia , Feminino , Hemianopsia/etiologia , Hemianopsia/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estimulação Luminosa/métodos , Psicofísica , Vias Visuais/patologia , Vias Visuais/fisiopatologiaRESUMO
DB, the first extensively tested blindsight case, has demonstrated the ability to detect and discriminate a range of visual stimuli presented within his perimetrically blind visual field [Weiskrantz L. (1986). Blindsight: A case study and implications. Oxford: Oxford University Press]. After initial reports of basic form discrimination (Weiskrantz, 1986), it later emerged that this ability to discriminate single stimuli presented to the blind field was probably based on the discrimination of orientation cues [Weiskrantz, L. (1987). Residual vision in a scotoma. A follow-up study of 'form' discrimination. Brain, 110, 77-92]. Even so, DB found it impossible to make a 'same/different' discrimination for pairs of stimuli in the blind field (Weiskrantz, 1986). In the current study, DB's discrimination and identification of stimuli on the basis of their form was tested (in 2AFC and FR paradigms). We have demonstrated that DB could successfully identify outline low contrast images of objects, make successful 'same/different' discriminations for pairs of stimuli presented in his blind field and identify complex images (digital photographs) presented entirely within his cortically blind field. The results are discussed in relation to the issues of likely neuronal mediation, the potential for improvement in cases of blindsight and the potential relevance of these findings in relation to theories of normal visual perception.
Assuntos
Discriminação Psicológica/fisiologia , Percepção de Forma/fisiologia , Hemianopsia/fisiopatologia , Reconhecimento Visual de Modelos/fisiologia , Campos Visuais/fisiologia , Idoso , Estudos de Casos e Controles , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estimulação Luminosa/métodosRESUMO
DB, the first blindsight case to be tested extensively (Weiskrantz, 1986) has demonstrated the ability to detect and discriminate a range of visual stimuli presented within his perimetrically blind visual field defect. In a temporal two alternative forced choice (2AFC) detection experiment we have investigated the limits of DB's detection ability within his field defect. Blind field performance was compared to his sighted field performance and to an age-matched control group (n=6). DB reliably detected the presence of a small (2 degrees ), low contrast (7%), 4.6c/ degrees Gabor patch with the same space-averaged luminance as the background presented within his blind field but performed at chance levels at the same eccentricity (11.3 degrees ) within his sighted field. Investigation of detection as a function of stimulus contrast revealed DB's ability to detect the presence of an 8% contrast stimulus within his blind field, compared to 12% in his sighted field. No significant difference in detection performance between DB's sighted field and the performance of six age-matched control participants suggests poor sighted field performance does not account for the results. Monocular testing also rules out differences between the eyes as an explanation, suggesting that DB demonstrates superior detection for certain stimuli within his visual field defect compared to normal vision.
Assuntos
Detecção de Sinal Psicológico , Percepção Visual , Comportamento de Escolha , Sensibilidades de Contraste , Humanos , Pessoa de Meia-Idade , Campos VisuaisRESUMO
Lesions of the occipital cortex result in areas of cortical blindness affecting the corresponding regions of the patient's visual field. The traditional view is that, aside from some spontaneous recovery in the first few months after the damage, when acute effects have subsided the areas of blindness are absolute and permanent. It has been found, however, that within such field defects some residual visual capacities may persist in the absence of acknowledged awareness by the subject (blindsight type 1) or impaired awareness (type 2). Neuronal pathways mediating blindsight have a specific and narrow spatial and temporal bandwidth. A group of cortically blind patients (n = 12) carried out a daily detection "training" task over a 3-month period, discriminating grating visual stimuli optimally configured for blindsight from homogeneous luminance-matched stimuli. No feedback was given during the training. Assessment of training was by psychophysical measurements carried out before and after training and included detection of a range of spatial frequencies (0.5-7 cycles per degree), contrast detection at 1 cycle per degree, clinical perimetry, and subjective estimates of visual field defect. The results show that repeated stimulation by appropriate visual stimuli can result in improvements in visual sensitivities in the very depths of the field defect.
Assuntos
Cegueira Cortical/fisiopatologia , Percepção Visual/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Conscientização , Estudos de Casos e Controles , Sensibilidades de Contraste , Discriminação Psicológica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Vias Neurais , Estimulação Luminosa , Psicofísica , Testes de Campo Visual , Campos Visuais/fisiologiaRESUMO
Blindsight is the ability of some cortically blind patients to discriminate visual events presented within their field defect. We have examined a fundamental aspect of visual processing, namely the detection of spatial structures presented within the field defect of 10 cortically blind patients. The method outlined is based on the detection of high-contrast stimuli and is effective in flagging a 'window of detection' in the spatial frequency spectrum, should it exist. Here we report on the presence of a narrowly tuned psychophysical spatial channel optimally responding to frequencies less than 4 cycles/ degrees in eight out of 10 patients tested. The two patients who did not show any evidence of blindsight appear to have intact midbrain structures, but have lesions that extend from the occipital cortex to the thalamus. In addition, we have recorded subjective reports of awareness of the visual events in each trial. Detection scores of eight blindsight patients were subsequently subdivided based on the subjective reports of awareness. It appears that the psychophysical spatial channel-mediating responses in the absence of any awareness of the visual event have a narrower frequency response than those involved when the patients report some awareness of the visual event. The findings are discussed in relation to previous reports on the incidence of blindsight and performance on tasks involving spatial processing.
Assuntos
Cegueira Cortical/fisiopatologia , Percepção Espacial/fisiologia , Campos Visuais/fisiologia , Adulto , Idoso , Conscientização , Mapeamento Encefálico , Sensibilidades de Contraste/fisiologia , Discriminação Psicológica , Feminino , Humanos , Imageamento por Ressonância Magnética/instrumentação , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Estimulação LuminosaRESUMO
Blindsight subjects are typically better at discriminating rapid, transient visual events than those with gradual on/off-sets. Surprisingly, the detailed investigation of temporal characteristics of mechanisms mediating blindsight is only reported in one subject (GY). It is of interest to establish whether these characteristics are similar to those in other cases of blindsight. Here, we report on a systematic study of spatio-temporal properties of mechanisms mediating blindsight in a subject VN. VN has a lower right quadranopia following surgical removal of the left occipital cortex above the calcarine sulcus, therefore, there are no remaining islands of intact visual cortex within this area. Similar to GY, the blindsight mechanisms in VN have narrowly tuned band-pass temporal characteristics with a peak sensitivity at 20Hz and above chance performance at temporal frequencies >/=10 and =33Hz. The spatial channel in VN has low-pass characteristics with an upper cut-off <3.5c/ degrees. There is extensive spatial summation in the blindfield whereas no temporal summation was found in the time range tested (50-1600ms). In agreement with our previous reports, pupillary responses can predict the existence of residual vision within the field defect and show similar spatial characteristics to those obtained psychophysically. The spatio-temporal characteristics of blindsight in VN reported here are similar to those reported in subjects with ischaemic lesions, suggesting that such visual capacities need not necessarily be attributed to spared areas of visual cortex.