China
Africa
Explore chapters and articles related to this topic
Dementia
Published in Henry J. Woodford, Essential Geriatrics, 2022
Home adaptations to address physical functional impairment may be required in addition to other adjustments (see page 29). Occupational therapist home visits are valuable. Orientation can be helped by clocks that also clearly display the date. Living spaces should be uncluttered but still feel homely. Visual perception can be affected. Dementia-friendly environments have increased contrast between walls and floor, handrails and walls, doors and walls and so on, to help compensate. Perceptual changes can also be used to limit unhelpful behaviours – e.g. painting the door to the outside the same colour as the surrounding wall to discourage wandering outdoors. Patterned designs or shiny surfaces can be confusing (e.g. flooring appearing like water) and should be minimised. The person may not see pale food on a pale plate or colourless liquid in a colourless glass. Consider using coloured plates and cups.
The Conceptual Basis of Mental Health Practice
Published in Cathy Laver-Bradbury, Margaret J.J. Thompson, Christopher Gale, Christine M. Hooper, Child and Adolescent Mental Health, 2021
‘Green’ is an idea that we need to understand before we can ‘see’ it. It is important to understand that our perception of reality responds to our pre-existing understanding of that reality. The psychological mechanisms involved in visual perception are the same as those found in hallucinations. Both vision and hallucinations are mental processes.
Sci-fi dreaming
Published in Josie Malinowski, The Psychology of Dreaming, 2020
Following this, they created the DeepDream Generator, which anyone can use by simply uploading an image and running it through the generator. The final image often ends up being very psychedelic: the sort of thing you might see if you’d taken a tab of acid (LSD) or gone on a magic mushroom (psilocybin) trip. Since DeepDream images are similar to acid-induced hallucinations, this might mean that what DeepDream is doing to artificial neural nets and what psychedelics do to human neural nets is also similar: superimposing patterns identified in the visual scene back onto the scene itself. Perception of visual layers in humans is usually an unconscious process, but under the influence of psychedelics, these layers may become superimposed into our conscious visual perception and even fed back repeatedly until we perceive the trippy world of psychedelic hallucination that’s part-normal reality and part-visual hallucination.
Impact of Degraded Optics on Monocular and Binocular Vision: Lessons from Recent Advances in Highly-Aberrated Eyes
Published in Seminars in Ophthalmology, 2022
Preetirupa Devi, Preetam Kumar, Bhagya Lakshmi Marella, Shrikant R. Bharadwaj
All these observations have significant implications for the clinical diagnosis and management of patients with highly aberrated optics. From a clinical diagnosis perspective, an increase in the eye’s HOAs seem to be an early marker for disease conditions like keratoconus and several metrics surrounding this aspect are being steadily accrued in the literature.78–80 However, a detailed discussion of this issue is beyond the scope of the present review. From a clinical management perspective, the following three implications may be derived from the results presented here. First, all these results reiterate the fact that human visual perception is a highly evolved and complex function, containing several dimensions that cannot be veridically represented using a single measure of high-contrast visual acuity. While high contrast acuity may be used ubiquitously as an outcome measure of disease severity and clinical management, it does not provide a holistic measure of the patient’s visual experience. Clinicians are therefore urged to look beyond high-contrast visual acuity as the sole outcome measure of their management of conditions described in this review (as much as for other disease conditions that are not part of this review). Including measures of contrast sensitivity and binocularity, among others, may provide a more comprehensive view of the patient’s visual experience, as shown here.
Visual perceptual deficit screening in stroke survivors: evaluation of current practice in the United Kingdom and Republic of Ireland
Published in Disability and Rehabilitation, 2022
Michael J. Colwell, Nele Demeyere, Kathleen Vancleef
Consistent with Vancleef et al. [12], we observed a disparate understanding of visual perception among clinician respondents. When provided a list of visual perceptual functions/deficits, most respondents (83%) were able to correctly identify these as belonging to visual perception. However, when provided a list of sensory vision functions/deficits, 48% of responses inaccurately identified these as visual perceptual. Further, 91% of respondents regarded visual neglect as a deficit of visual perception, contrasting with literature which considers it an attentional processing deficit [11]. Incongruence in how sensory vision and visual perception are understood appears problematic, particularly where exact and consistent language is relied upon in information exchanges to inform clinical decision-making, such as in referral reports. Inconsistencies between referrals from stroke units to orthoptics and subsequent orthoptic diagnoses have been highlighted previously [37,38].
Current practice and challenges in screening for visual perception deficits after stroke: a qualitative study
Published in Disability and Rehabilitation, 2022
Kathleen Vancleef, Michael J. Colwell, Olivia Hewitt, Nele Demeyere
Visual perception is the dynamic process of perceiving the environment through sensory inputs and translating the sensory input into meaningful concepts associated with visual knowledge of the environment [1]. Visual perception problems are therefore distinct from sensory visual impairments such as reduced visual acuity, visual field and eye movements [2]. Where sensory visual impairments result from damage to the eye or early visual pathways from the eye to the primary visual cortex, visual perception deficits are attributed to impaired function in later visual processing areas in the occipital, parietal and temporal cortex [3]. Examples of visual perceptual deficits include apperceptive and associative agnosia (object recognition difficulties), prosopagnosia (face recognition difficulties), akinetopsia (difficulties in perceiving motion), achromatopsia (difficulties in perceiving colour), problems in visual memory (remembering what you have seen before), and in visuospatial abilities (e.g., judging distances or spatial relations between objects) [3]. Visual inattention or hemispatial neglect is sometimes considered to be part of visual perception [1,4], though neuropsychology research attributes this to an attentional deficit [5]. In particular, the presence of preserved perception when attention is stretched to focus on the stimuli, the existence of cross-modal neglect and manipulations of stimulus density on the extent of neglect support the classification of hemispatial neglect as a disorder of attention [6,7].