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1.
Sci Rep ; 12(1): 18938, 2022 11 07.
Article in English | MEDLINE | ID: mdl-36344534

ABSTRACT

Data from eight numerosity estimation experiments reliably exhibit wave-like patterns in plots of the standard deviations of the response times along the abstract parameter of the magnitude of the error in the numerosity estimation. An explanation for this phenomenon is proposed in terms of an analogy between response times and error magnitude on one hand, and energy and position of quantum particles on the other, constructed using an argument for an overlap between the mathematical apparatus describing Hopfield-type neural networks and quantum systems, established by some researchers. Alternative explanations are presented within the traditional explanatory framework of oscillations due to neural firing, involving hypothetical mechanisms for converting oscillation patterns in time to oscillation patterns in the space of an abstract parameter, such as the magnitude of the error during numerosity estimation. The viability of the proposal of causal influences propagating from the microscale of quantum phenomena to the macroscale of human behavior, needed for the first type of explanation, is exemplified by the phenomenon of magnetoreception in some species of birds, which is allegedly quantum in nature.


Subject(s)
Brain , Neural Networks, Computer , Humans , Brain/physiology , Reaction Time
2.
Atten Percept Psychophys ; 82(4): 1566-1572, 2020 May.
Article in English | MEDLINE | ID: mdl-31898063

ABSTRACT

Readers can acquire useful information from only a narrow region of text around each fixation (the perceptual span), which extends asymmetrically in the direction of reading. Studies with bilingual readers have additionally shown that this asymmetry reverses with changes in horizontal reading direction. However, little is known about the perceptual span's flexibility following orthogonal (vertical vs. horizontal) changes in reading direction, because of the scarcity of vertical writing systems and because changes in reading direction often are confounded with text orientation. Accordingly, we assessed effects in a language (Mongolian) that avoids this confound, in which text is conventionally read vertically but can also be read horizontally. Sentences were presented normally or in a gaze-contingent paradigm in which a restricted region of text was displayed normally around each fixation and other text was degraded. The perceptual span effects on reading rates were similar in both reading directions. These findings therefore provide a unique (nonconfounded) demonstration of perceptual span flexibility.


Subject(s)
Eye Movements/physiology , Multilingualism , Reading , Adolescent , Female , Fixation, Ocular/physiology , Humans , Language , Male , Orientation/physiology , Orientation, Spatial/physiology , Random Allocation , Writing , Young Adult
3.
BMJ Open ; 9(7): e026405, 2019 07 09.
Article in English | MEDLINE | ID: mdl-31289067

ABSTRACT

AIM: To examine system characteristics associated with variations in unplanned admission rates in those aged 85+. DESIGN: Mixed methods. SETTING: Primary care trusts in England were ranked according to changes in admission rates for people aged 85+ between 2007 and 2009, and study sites selected from each end of the distribution: three 'improving' sites where rates had declined by more than 4% and three 'deteriorating' sites where rates had increased by more than 20%. Each site comprised an acute hospital trust, its linked primary care trust/clinical commissioning group, the provider of community health services and adult social care. PARTICIPANTS: A total of 142 representatives from these organisations were interviewed to understand how policies had been developed and implemented. McKinsey's 7S framework was used as a structure for investigation and analysis. RESULTS: In general, improving sites provided more evidence of comprehensive system focused strategies backed by strong leadership, enabling the development and implementation of policies and procedures to avoid unnecessary admissions of older people. In these sites, primary and intermediate care services appeared more comprehensive and better integrated with other parts of the system, and policies in emergency departments were more focused on providing alternatives to admission. CONCLUSIONS: Health and social care communities which have attenuated admissions of people aged 85+ prioritised developing a shared vision and strategy, with sustained implementation of a suite of interventions.


Subject(s)
Emergency Medical Service Communication Systems/statistics & numerical data , Emergency Service, Hospital/organization & administration , Hospitalization/statistics & numerical data , Aged, 80 and over , Analysis of Variance , Clinical Coding , England , Evaluation Studies as Topic , Female , Humans , Male , Qualitative Research
4.
J Health Psychol ; 24(10): 1318-1333, 2019 09.
Article in English | MEDLINE | ID: mdl-28847166

ABSTRACT

Cognitive behavioural therapy and graded exercise therapy are promoted as evidence-based treatments for myalgic encephalomyelitis/chronic fatigue syndrome. This article explores patients' symptom responses following these treatments versus pacing therapy, an approach favoured by many sufferers. We analyse data from a large cross-sectional patient survey (n = 1428) and compare our findings with those from comparable patient surveys (n = 16,665), using a mix of descriptive statistics and regression analysis modelling. Findings from analysis of primary and secondary surveys suggest that cognitive behavioural therapy is of benefit to a small percentage of patients (8%-35%), graded exercise therapy brings about large negative responses in patients (54%-74%), while pacing is the most favoured treatment with the lowest negative response rate and the highest reported benefit (44%-82%).


Subject(s)
Cognitive Behavioral Therapy , Exercise Therapy/methods , Fatigue Syndrome, Chronic/therapy , Adolescent , Adult , Aged , Combined Modality Therapy , Cross-Sectional Studies , Fatigue Syndrome, Chronic/diagnosis , Fatigue Syndrome, Chronic/psychology , Female , Health Surveys , Humans , Male , Middle Aged , Patient Satisfaction/statistics & numerical data , Self Care/methods , Treatment Outcome , Young Adult
5.
Prim Health Care Res Dev ; 19(1): 53-63, 2018 01.
Article in English | MEDLINE | ID: mdl-28899447

ABSTRACT

Aim To examine how the introduction of intensive community support (ICS) affected admissions to community hospital (CH) and to explore the views of patients, carers and health professionals on this transition. BACKGROUND: ICS was introduced to provide an alternative to CH provision for patients (mostly very elderly) requiring general rehabilitation. METHOD: Routine data from both services were analysed to identify the number of admissions and length of stay between September 2012 and September 2014. In total, 10 patients took part in qualitative interviews. Qualitative interviews and focus groups were undertaken with 19 staff members, including managers and clinicians. Findings There were 5653 admissions to CH and 1710 to ICS between September 2012 and September 2014. In the five months before the introduction of ICS, admission rates to CH were on average 217/month; in the final five months of the study, when both services were fully operational, average numbers of patients admitted were: CH 162 (a 25% reduction), ICS 97, total 259 (a 19% increase). Patients and carers rated both ICS and CH favourably compared with acute hospital care. Those who had experienced both services felt each to be appropriate at the time; they appreciated the 24 h availability of staff in CH when they were more dependent, and the convenience of being at home after they had improved. In general, staff welcomed the introduction of ICS and appreciated the advantages of home-based rehabilitation. Managers had a clearer vision of ICS than staff on the ground, some of whom felt underprepared to work in the community. There was a consensus that ICS was managing less complex and dependent patients than had been envisaged. CONCLUSION: ICS can provide a feasible adjunct to CH that is acceptable to patients. More work is needed to promote the vision of ICS amongst staff in both community and acute sectors.


Subject(s)
Caregivers/statistics & numerical data , Community Health Services/methods , Community Health Services/statistics & numerical data , Hospitalization/statistics & numerical data , Hospitals, Community/statistics & numerical data , Adult , Aged , Aged, 80 and over , Attitude of Health Personnel , Female , Focus Groups , Humans , Interviews as Topic , Length of Stay/statistics & numerical data , Male
6.
Front Psychol ; 8: 807, 2017.
Article in English | MEDLINE | ID: mdl-28769827

ABSTRACT

Printed words are complex visual stimuli containing a range of different spatial frequencies, and several studies have suggested that various spatial frequencies are effective for skilled adult reading. But while it is well known that the area of text from which information is acquired during reading extends to the left and right of each fixation, the effectiveness of spatial frequencies falling each side of fixation has yet to be determined. To investigate this issue, we used a spatial frequency adaptation of the gaze-contingent moving-window paradigm in which sentences were shown to skilled adult readers either entirely as normal or filtered to contain only low, medium, or high spatial frequencies except for a window of normal text around each point of fixation. Windows replaced filtered text either symmetrically 1 character to the left and right of each fixated character, or asymmetrically, 1 character to the left and 7 or 13 to the right, or 1 character to the right and 7 or 13 to the left. Reading times and eye-movement measures showed that reading performance for sentences presented entirely as normal generally changed very little with filtered displays when windows extended to the right but was often disrupted when windows extended to the left. However, asymmetrical windows affected performance on both sides of fixation. Indeed, increasing the leftward extent of windows from 7 to 13 characters produced decreases in both reading times and fixation durations, suggesting that reading was influenced by the spatial frequency content of leftward areas of text some considerable distance from fixation. Overall, the findings show that while a range of different spatial frequencies can be used by skilled adult readers, the effectiveness of spatial frequencies differs for text on each side of central vision, and may reflect different roles played by these two areas of text during reading.

7.
Front Psychol ; 7: 1433, 2016.
Article in English | MEDLINE | ID: mdl-27733837

ABSTRACT

Recent research has shown that differences in the effectiveness of spatial frequencies for fast and slow skilled adult readers may be an important component of differences in reading ability in the skilled adult reading population (Jordan et al., 2016a). But the precise nature of this influence on lexical processing during reading remains to be fully determined. Accordingly, to gain more insight into the use of spatial frequencies by skilled adult readers with fast and slow reading abilities, the present study looked at effects of spatial frequencies on the processing of specific target words in sentences. These target words were of either high or low lexical frequency and each sentence was displayed as normal or filtered to contain only very low, low, medium, high, or very high spatial frequencies. Eye movement behavior for target words was closest to normal for each reading ability when text was shown in medium or higher spatial frequency displays, although reading occurred for all spatial frequencies. Moreover, typical word frequency effects (the processing advantage for words with higher lexical frequencies) were observed for each reading ability across a broad range of spatial frequencies, indicating that many different spatial frequencies provide access to lexical representations during textual reading for both fast and slow skilled adult readers. Crucially, however, target word fixations were fewer and shorter for fast readers than for slow readers for all display types, and this advantage for fast readers appeared to be similar for normal, medium, high, and very high spatial frequencies but larger for low and very low spatial frequencies. Therefore, although fast and slow skilled adult readers can both use a broad range of spatial frequencies when reading, fast readers make more effective use of these spatial frequencies, and especially those that are lower, when processing the identities of words.

8.
J Exp Psychol Hum Percept Perform ; 42(8): 1066-71, 2016 08.
Article in English | MEDLINE | ID: mdl-27123680

ABSTRACT

Text contains a range of different spatial frequencies but the effectiveness of spatial frequencies for normal variations in skilled adult reading ability is unknown. Accordingly, young skilled adult readers showing fast or slow reading ability read sentences displayed as normal or filtered to contain only very low, low, medium, high, or very high spatial frequencies. Reading times and eye movement measures of fixations and saccades assessed the effectiveness of these displays for reading. Reading times showed that, for each reading ability, medium, high, and very high spatial frequencies were all more effective than lower spatial frequencies. Indeed, for each reading ability, reading times for normal text were maintained when text contained only medium, high, or very high spatial frequencies. However, reading times for normal text and for each spatial frequency were all substantially shorter for fast readers than for slow readers, and this advantage for fast readers was similar for normal, medium, high, and very high spatial frequencies but much larger for low and very low spatial frequencies. In addition, fast readers made fewer and shorter fixations, fewer and shorter regressions, and longer forward saccades, than slow readers, and these differences were generally similar in size for normal, medium, high, and very high spatial frequencies, but larger when spatial frequencies were lower. These findings suggest that fast and slow adult readers can each use a range of different spatial frequencies for reading but fast readers make more effective use of these spatial frequencies and especially those that are lower. (PsycINFO Database Record


Subject(s)
Eye Movements/physiology , Pattern Recognition, Visual/physiology , Psychomotor Performance/physiology , Reading , Adolescent , Adult , Comprehension/physiology , Female , Humans , Male , Time Factors , Young Adult
9.
J Exp Psychol Learn Mem Cogn ; 42(2): 296-307, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26322828

ABSTRACT

When reading from left to right, useful information acquired during each fixational pause is widely assumed to extend 14 to 15 characters to the right of fixation but just 3 to 4 characters to the left, and certainly no further than the beginning of the fixated word. However, this leftward extent is strikingly small and seems inconsistent with other aspects of reading performance and with the general horizontal symmetry of visual input. Accordingly, 2 experiments were conducted to examine the influence of text located to the left of fixation during each fixational pause using an eye-tracking paradigm in which invisible boundaries were created in sentence displays. Each boundary corresponded to the leftmost edge of each word so that, as each sentence was read, the normal letter content of text to the left of each fixated word was corrupted by letter replacements that were either visually similar or visually dissimilar to the originals. The proximity of corrupted text to the left of fixation was maintained at 1, 2, 3, or 4 words from the left boundary of each fixated word. In both experiments, relative to completely normal text, reading performance was impaired when each type of letter replacement was up to 2 words to the left of fixated words but letter replacements further from fixation produced no impairment. These findings suggest that key aspects of reading are influenced by information acquired during each fixational pause from much further leftward than is usually assumed. Some of the implications of these findings for reading are discussed.


Subject(s)
Fixation, Ocular , Reading , Adolescent , Adult , Eye Movement Measurements , Humans , Language Tests , Pattern Recognition, Visual , Psychological Tests , Time , Young Adult
10.
PLoS One ; 6(9): e23957, 2011.
Article in English | MEDLINE | ID: mdl-21935368

ABSTRACT

BACKGROUND: The existence and function of unilateral hemispheric projections within foveal vision may substantially affect foveal word recognition. The purpose of this research was to reveal these projections and determine their functionality. METHODOLOGY: Single words (and pseudowords) were presented to the left or right of fixation, entirely within either foveal or extrafoveal vision. To maximize the likelihood of unilateral projections for foveal displays, stimuli in foveal vision were presented away from the midline. The processing of stimuli in each location was assessed by combining behavioural measures (reaction times, accuracy) with on-line monitoring of hemispheric activity using event-related potentials recorded over each hemisphere, and carefully-controlled presentation procedures using an eye-tracker linked to a fixation-contingent display. PRINCIPAL FINDINGS: Event-related potentials 100-150 ms and 150-200 ms after stimulus onset indicated that stimuli in extrafoveal and foveal locations were projected unilaterally to the hemisphere contralateral to the presentation hemifield with no concurrent projection to the ipsilateral hemisphere. These effects were similar for words and pseudowords, suggesting this early division occurred before word recognition. Indeed, event-related potentials revealed differences between words and pseudowords 300-350 ms after stimulus onset, for foveal and extrafoveal locations, indicating that word recognition had now occurred. However, these later event-related potentials also revealed that the hemispheric division observed previously was no longer present for foveal locations but remained for extrafoveal locations. These findings closely matched the behavioural finding that foveal locations produced similar performance each side of fixation but extrafoveal locations produced left-right asymmetries. CONCLUSIONS: These findings indicate that an initial division in unilateral hemispheric projections occurs in foveal vision away from the midline but is not apparent, or functional, when foveal word recognition actually occurs. In contrast, the division in unilateral hemispheric projections that occurs in extrafoveal locations is still apparent, and is functional, when extrafoveal word recognition takes place.


Subject(s)
Evoked Potentials , Fovea Centralis/physiology , Pattern Recognition, Visual , Adolescent , Adult , Behavior , Brain Mapping/methods , Electroencephalography/methods , Fixation, Ocular , Functional Laterality , Humans , Reaction Time , Reading , Reproducibility of Results , Research Design , Time Factors , Vision, Ocular , Visual Fields
11.
Cortex ; 46(3): 298-309, 2010 Mar.
Article in English | MEDLINE | ID: mdl-19576580

ABSTRACT

It has been claimed that word recognition is affected fundamentally by the precise location at which a word is fixated because a precise split in hemispheric processing at the point of fixation causes all letters to the left and right of fixation to project to different, contralateral hemispheres. To assess this claim, 5-letter words (and nonwords) were presented for lexical decision when participants fixated the space immediately to the left (location 1) or right (location 6) of each stimulus, or one of the four possible inter-letter spaces (locations 2-5). Fixation location was controlled using an eye-tracker linked to a fixation-contingent display and all stimuli were presented entirely within foveal vision to avoid confounding influences of extrafoveal hemispheric projections. Performance was equally poorest when fixating locations 1 and 6 (when words were shown entirely to either the right and left of fixation), intermediate for location 5, and equally superior for locations 2, 3, and 4. Additional word-specific analyses also showed no evidence of the effects of fixation location on optimal word recognition predicted by split-fovea processing. These findings suggest that, while fixation location influences word recognition, word recognition is apparently not affected by a split in hemispheric processing at the point of fixation and does not depend critically on the precise location at which a word is fixated. Implications of these findings for the role of fixation location in word recognition are discussed.


Subject(s)
Fixation, Ocular , Fovea Centralis , Functional Laterality , Pattern Recognition, Visual , Reading , Analysis of Variance , Eye Movement Measurements , Humans , Neuropsychological Tests , Photic Stimulation , Reaction Time , Recognition, Psychology , Vocabulary
12.
Cortex ; 46(1): 100-5, 2010 Jan.
Article in English | MEDLINE | ID: mdl-19147129

ABSTRACT

Several studies have claimed that, when fixating a word, a precise split in foveal processing causes all letters to the left and right of fixation to project to different, contralateral hemispheres (split-fovea theory--SFT). In support of this claim, Lavidor et al. (2001; hereafter LES&B) reported that lexical decisions were affected by the number of letters to the left of fixation but not the right, and that this indicates a functional division in hemispheric processing at the point of fixation. Jordan, Paterson, and Stachurski (Cortex, 2009; hereafter JP&S) re-evaluated these claims over 3 experiments using LES&B's original stimuli and procedures and found no support for the findings of LES&B. Following LES&B, JP&S presented stimuli binocularly (i.e., as in normal viewing). However, this procedure has its own complications for SFT (and for assessing the validity of the theory) because the two eyes often do not fixate the same location. Consequently, we report two further experiments which used an eye-tracker to ensure fixation accuracy and monocular viewing to eliminate influences of fixation disparity. Experiment 1 used the same-sized typeface as JP&S, and Experiment 2 used a larger typeface to approximate normal reading size. In line with the findings of JP&S, neither experiment could replicate the findings of LES&B and both experiments showed simply that word recognition was easier when fixations were made towards the beginning of words. Thus, after a total of 5 separate experiments, using binocular and monocular viewing conditions and stimuli presented in a range of sizes, none of these experiments has been able to replicate the findings of LES&B or provide any evidence for a functional division in hemispheric processing at the point of fixation.


Subject(s)
Fovea Centralis/physiology , Functional Laterality/physiology , Pattern Recognition, Visual/physiology , Vision Disparity/physiology , Vocabulary , Adult , Analysis of Variance , Discrimination, Psychological/physiology , Fixation, Ocular/physiology , Humans , Photic Stimulation , Psychomotor Performance/physiology , Reaction Time/physiology , Reading , Surveys and Questionnaires , Verbal Behavior , Vision, Ocular/physiology , Visual Fields/physiology
13.
J Exp Psychol Hum Percept Perform ; 35(6): 1961-8, 2009 Dec.
Article in English | MEDLINE | ID: mdl-19968446

ABSTRACT

It has been claimed that the recognition of words displayed in isolation is affected by the precise location at which they are fixated. However, this putative role for fixation location has yet to be reconciled with the finding from reading research that binocular fixations are often misaligned and, therefore, more than 1 location in a word is often fixated simultaneously. The accuracy and alignment of binocular fixations during single word processing have not been assessed previously. To investigate this issue, words were presented for lexical decision at locations around a central fixation point. Eye-tracking data revealed that participants often fixated inaccurately and that fixations were frequently misaligned, but that this did not affect word recognition. The findings show that binocular fixation disparity is pervasive even in single word displays and a potential source of confound for research into effects of fixation location on word recognition.


Subject(s)
Fixation, Ocular/physiology , Language , Pattern Recognition, Visual/physiology , Vision, Binocular/physiology , Decision Making/physiology , Humans , Photic Stimulation , Psychomotor Performance/physiology
14.
Cogn Affect Behav Neurosci ; 9(1): 113-21, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19246332

ABSTRACT

Many studies have claimed that hemispheric projections are split precisely at the foveal midline and so hemispheric asymmetry affects word recognition right up to the point of fixation. To investigate this claim, four-letter words and nonwords were presented to the left or right of fixation, either close to fixation in foveal vision or farther from fixation in extrafoveal vision. Presentation accuracy was controlled using an eyetracker linked to a fixation-contingent display. Words presented foveally produced identical performance on each side of fixation, but words presented extrafoveally showed a clear left-hemisphere (LH) advantage. Nonwords produced no evidence of hemispheric asymmetry in any location. Foveal stimuli also produced an identical word-nonword effect on each side of fixation, whereas extrafoveal stimuli produced a word-nonword effect only for LH (not right-hemisphere) displays. These findings indicate that functional unilateral projections to contralateral hemispheres exist in extrafoveal locations but provide no evidence of a functional division in hemispheric processing at fixation.


Subject(s)
Fovea Centralis/physiology , Pattern Recognition, Visual/physiology , Recognition, Psychology/physiology , Retina/physiology , Visual Fields/physiology , Vocabulary , Adolescent , Adult , Analysis of Variance , Fixation, Ocular/physiology , Functional Laterality , Humans , Photic Stimulation/methods , Reaction Time/physiology , Young Adult
15.
Neuropsychologia ; 47(8-9): 2004-7, 2009 Jul.
Article in English | MEDLINE | ID: mdl-19133280

ABSTRACT

Many studies have claimed that hemispheric processing is split precisely at the foveal midline and so place great emphasis on the precise location at which words are fixated. These claims are based on experiments in which a variety of fixation procedures were used to ensure fixation accuracy but the effectiveness of these procedures is unclear. We investigated this issue using procedures matched to the original studies and an eye-tracker to monitor the locations actually fixated. Four common types of fixation cues were used: cross, two vertical gapped lines, two vertical gapped lines plus a secondary task in which a digit was presented at the designated fixation point, and a dot. Accurate fixations occurred on <35% of trials for all fixation conditions. Moreover, despite the usefulness often attributed to a secondary task, no increase in fixation accuracy was produced in this condition. The indications are that split-fovea theory should not assume that fixation of specified locations occurs in experiments without appropriate eye-tracking control or, indeed, that consistent fixation of specified locations is plausible under normal conditions of word recognition.


Subject(s)
Cues , Fixation, Ocular/physiology , Functional Laterality/physiology , Recognition, Psychology/physiology , Visual Fields/physiology , Vocabulary , Humans , Pattern Recognition, Visual/physiology , Photic Stimulation/methods , Reaction Time/physiology
16.
Appl Opt ; 42(13): 2327-8, 2003 May 01.
Article in English | MEDLINE | ID: mdl-12737464

ABSTRACT

We present refractometric measurements made in the 266-1064-nm spectral region with a pulsed Nd:YAG laser, and the second, third, and fourth harmonics of the laser's fundamental wavelength. The critical angle is determined by the disappearance of the diffraction orders from a metal grating, forming a microcuvette with the prism's reflecting wall. A fused-silica measuring prism is used in the experiments.

17.
Appl Opt ; 41(9): 1677-84, 2002 Mar 20.
Article in English | MEDLINE | ID: mdl-11921795

ABSTRACT

Hermite-Gaussian modes in geometrically unconfined resonators with a four-level system saturable gain guide inside are experimentally observed and proved. The gain guide was formed with a polished cylindrical surface low-concentration Nd:YAG rod exposed to isotropic pump radiation. The connection of the mode scaling factor with the system parameters is compared with the theory. The abilities of the recently established gain-saturation guiding mechanism to support the generation of beams with wide tops and rapidly decreasing intensity in the wings are also experimentally proved. Application areas for saturable gain guiding are briefly discussed.

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