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PubMed2004

Increasing social and psychological information conveyed to General Practitioners after bad news consultations by use of separate letters from the Lung Cancer Nurse Specialist.

Multidisciplinary teams (MDT) now review all cases of lung cancer. These teams include a Lung Cancer Nurse Specialist (LCNS). These Nurses help support the patient and should facilitate communication and liaise with other services. The LCNS is present when the diagnosis is given to the patient but also usually spends time afterwards with the patient and their family. We postulated that a separate letter from the LCNS to the General Practitioner (GP) after the consultations would convey extra information to the GP. In 58 new lung cancer patients reviewed in the clinic, the LCNS and Physician independently wrote separate letters after the consultation in which the diagnosis of lung cancer was given. The GPs were asked by questionnaire about the usefulness of the letter from the LCNS. This letter was considered by the GP to provide extra information in: (i) 69% concerning the patients reaction to the diagnosis; (ii) 85% concerning who attended the clinic with the patient; (iii) 85% about what referrals were made to community services; (iv) 86% about who the patient was living with; (v) 81% about who the patients carers were; (vi) 81% information on the patients condition; (vii) 70% concerning the information given to patients about benefits. Ninety-seven percent of the GPs found the LCNS letter useful or very useful and 92% of the GPs thought that the information in the letter would be useful or very useful when they next saw the patient. Separate and independent letters from the LCNS after "bad news" consultation in lung cancer provides added useful information for GPs. Ninety-one percent of the GPs wanted the letters from the LCNS to continue.

Communication↗
PubMed1993

The bilateral field advantage on a letter-matching task.

A series of studies have reported that responding is faster when letter pairs to be matched are projected to two hemispheres rather than one. Four experiments described here tested this bilateral field advantage and identified factors that influence its extent. Subjects were shown letter pairs drawn from the ensemble "AaBb", and classified the letter pairs as "Match" if the letters had the same name (regardless of case) and "No Match" if they did not. In the first two experiments the letter pairs were presented unilaterally (both letters in one visual field), bilaterally (one letter in each visual field), or centrally (both letters on the vertical midline, above and below fixation), in order to investigate how the bilateral field advantage is influenced by screen location. The third experiment added a bilateral-diagonal position (to check for artefacts related to horizontal scanning strategies), and the fourth experiment added distractor digits (to equate initial processing demands in the bilateral and unilateral conditions). Results indicate that the bilateral field advantage is a robust phenomenon, although several manipulations reduced its magnitude. Implications of these findings for models of hemispheric collaboration and interhemispheric processing are discussed.

Adolescent↗
PubMed2001

Psychophysics of reading. XX. Linking letter recognition to reading speed in central and peripheral vision.

Our goal is to link spatial and temporal properties of letter recognition to reading speed for text viewed centrally or in peripheral vision. We propose that the size of the visual span - the number of letters recognizable in a glance - imposes a fundamental limit on reading speed, and that shrinkage of the visual span in peripheral vision accounts for slower peripheral reading. In Experiment 1, we estimated the size of the visual span in the lower visual field by measuring RSVP (rapid serial visual presentation) reading times as a function of word length. The size of the visual span decreased from at least 10 letters in central vision to 1.7 letters at 15 degrees eccentricity, in good agreement with the corresponding reduction of reading speed measured by Chung and coworkers (Chung, S. T. L., Mansfield, J. S., & Legge, G. E. (1998). Psychophysics of reading. XVIII. The effect of print size on reading speed in normal peripheral vision. Vision Research, 38, 2949-2962). In Exp. 2, we measured letter recognition for trigrams (random strings of three letters) as a function of their position on horizontal lines passing through fixation (central vision) or displaced downward into the lower visual field (5, 10 and 20 degrees ). We also varied trigram presentation time. We used these data to construct visual-span profiles of letter accuracy versus letter position. These profiles were used as input to a parameter-free model whose output was RSVP reading speed. A version of this model containing a simple lexical-matching rule accounted for RSVP reading speed in central vision. Failure of this version of the model in peripheral vision indicated that people rely more on lexical inference to support peripheral reading. We conclude that spatiotemporal characteristics of the visual span limit RSVP reading speed in central vision, and that shrinkage of the visual span results in slower reading in peripheral vision.

Analysis of Variance↗
PubMed1998

Vernier and letter acuities for low-pass filtered moving stimuli.

Vernier and letter acuities are both susceptible to degradation by image motion. In a previous study, we showed that the worsening of Vernier acuity for stimuli moving up to 4 degrees/s is accounted for primarily by a shift of visual sensitivity to mechanisms of lower spatial frequency. The purposes of this study were to extend the previous results for Vernier acuity to higher stimulus contrast and velocities, and to determine if a shift in spatial scale can similarly explain the degradation of letter acuity for moving stimuli. We measured Vernier discrimination for a pair of vertical abutting thin lines and letter resolution for a four-orientation letter 'T' as a function of stimulus velocity ranging from 0 to 12 degrees/s. Stimuli were presented at 20 times the detection threshold, determined for each velocity. To determine the spatial-frequency mechanism that mediates each task at each velocity, we measured Vernier and letter acuities with low-pass filtered stimuli (cut-off spatial-frequency: 17.1-1.67 c/deg) and analyzed the data using an equivalent blur analysis. Our results show that the empirically determined, equivalent intrinsic blur associated with both tasks increases as a function of stimulus velocity, suggesting corresponding increases in the size of optimally responding mechanisms. This progressive increase in mechanism size can account for the worsening of Vernier and letter acuities with velocity. Vernier discrimination is found to be more susceptible to degradation by various stimulus parameters than letter resolution, suggesting that different mechanisms are involved in the two tasks. We conclude that the elevations in Vernier and letter acuities for moving stimuli are the consequence of a shift of visual sensitivity toward mechanisms of lower spatial frequencies.

Female↗
PubMed1999

Identification of band-pass filtered letters and faces by human and ideal observers.

To better understand how the visual system makes use of information across spatial scales when identifying different kinds of complex patterns, we measured human and ideal contrast identification thresholds to estimate identification efficiency for 1- and 2-octave wide band-pass filtered letters and faces embedded in 2-D dynamic Gaussian noise. Varying stimulus center frequency from 1 to 70 c/object had different effects on letter and face identification efficiency. In the 2-octave conditions, identification efficiencies decreased by 0.25-0.5 log units for letters and 0.5-1.2 log units for faces as center frequency increased from 6.2 to 49.5 c/object, but only letters were identifiable at center frequencies below 6.2 c/object. In the 1-octave conditions, letter identification efficiencies increased by about 0.5 log units as center frequency increased from 1.1 to 2.2 c/object, and were nearly constant from 2.2 to 35 c/object. Letters were unidentifiable by human observers at 70 c/object. Surprisingly, face identification was impossible for human observers at all center frequencies except 8.8 c/object for one observer, and 8.8 and 17.5 c/object for a second observer. Ideal observer thresholds were obtained for both letters and faces in all conditions, so information was always available to perform the task. Thus, the failure to identify faces reflects constraints on visual processing rather than a lack of stimulus information. Selective spatial sampling may account for some of the differences between letter and face identification efficiencies.

Contrast Sensitivity↗
PubMed2001

The effect of a combined influenza/pneumococcal immunization reminder letter.

BACKGROUND: The effect of a combined influenza and pneumococcal immunization reminder letter on increasing influenza and pneumococcal immunization rates, and the timeliness of receiving immunizations after receipt of a reminder letter, have not been examined. This study addresses these issues using a sample of new Medicare beneficiaries residing in Hawaii. METHODS: Newly enrolled Medicare beneficiaries in Hawaii from 25 September 1995 through 31 August 1996 were randomly assigned to one of three groups: Group 1, no letter (n=2144); Group 2, influenza immunization reminder letter only (n=2213); or Group 3, pneumococcal and influenza immunization reminder letter (n=2171). Health Care Financing Administration claims data were compared among groups. RESULTS: In Group 3, the influenza immunization rate increased 3.8 percentage points (n=87; p=0.017) compared with Group 1. The Group 3 pneumococcal immunization rate increased 3.5 percentage points (n=78; p<0.001) compared to Group 1 and 4.0 percentage points (n=86; p<0.001) compared to Group 2. Sixty-six beneficiaries in Group 3 received simultaneous pneumococcal and influenza immunizations, a significant difference compared to Group 1 or Group 2. Increases in immunizations were observed immediately following the reminder letters and the effect persisted for 5 to 7 weeks. CONCLUSIONS: The combination letter increased both influenza and pneumococcal immunization rates and the simultaneous administration of immunizations without detrimental effect to influenza immunization rates. A combined reminder letter is inexpensive and recommended as part of a multicomponent campaign for adult immunization.

Aged↗
PubMed1999

Unconscious letter discrimination is enhanced by association with conscious color perception in visual form agnosia.

Adaptive behavior guided by unconscious visual cues occurs in patients with various kinds of brain damage as well as in normal observers, all of whom can process visual information of which they are fully unaware [1] [2] [3] [4] [5] [6] [7] [8]. Little is known on the possibility that unconscious vision is influenced by visual cues that have access to consciousness [9]. Here we report a 'blind' letter discrimination induced through a semantic interaction with conscious color processing in a patient who is agnosic for visual shapes, but has normal color vision and visual imagery. In seeing the initial letters of color names printed in different colors, it is normally easier to name the print color when it is congruent with the initial letter of the color name than when it is not [10]. The patient could discriminate the initial letters of the words 'red' and 'green' printed in the corresponding colors significantly above chance but without any conscious accompaniment, whereas he performed at chance with the reverse color-letter mapping as well as in standard tests of letter reading. We suggest that the consciously perceived colors activated a representation of the corresponding word names and their component letters, which in turn brought out a partially successful, unconscious processing of visual inputs corresponding to the activated letter representations.

Adult↗
PubMed1989

Types and tokens in visual letter perception.

Five experiments demonstrate that in briefly presented displays, subjects have difficulty distinguishing repeated instances of a letter or digit (multiple tokens of the same type). When subjects were asked to estimate the numerosity of a display, reports were lower for displays containing repeated letters, for example, DDDD, than for displays containing distinct letters, for example, NRVT. This homogeneity effect depends on the common visual form of adjacent letters. A distinct homogeneity effect, one that depends on the repetition of abstract letter identities, was also found: When subjects were asked to report the number of As and Es in a display, performance was poorer on displays containing two instances of a target letter, one appearing in uppercase and the other in lowercase, than on displays containing one of each target letter. This effect must be due to the repetition of identities, because visual form is not repeated in these mixed-case displays. Further experiments showed that this effect was not influenced by the context surrounding the target letters, and that it can be tied to limitations in attentional processing. The results are interpreted in terms of a model in which parallel encoding processes are capable of automatically analyzing information from several regions of the visual field simultaneously, but fail to accurately encode location information. The resulting representation is thus insufficient to distinguish one token from another because two tokens of a given type differ only in location. However, with serial attentional processing multiple tokens can be kept distinct, pointing to yet another limit on the ability to process visual information in parallel.

Attention↗
PubMed1982

Experimental test of contemporary mathematical models of visual letter recognition.

A letter confusion experiment that used brief durations manipulated payoffs across the four stimulus letters, which were composed of line segments equal in length. The observers were required to report the features they perceived as well as to give a letter response. The early feature-sampling process is separated from the later letter-decision process in the substantive feature models, and predictions are thus obtained for the frequencies of feature report as well as letter report. Four substantive visual feature-processing models are developed and tested against one another and against three models of a more descriptive nature. The substantive models predict the decisional letter report phase much better than they do the feature-sampling phase, but the best overall 4 X 4 letter confusion matrix fits are obtained with one of the descriptive models, the similarity choice model. The present and other recent results suggest that the assumption that features are sampled in a stochastically independent manner may not be generally valid. The traditional high-threshold conceptualization of feature sampling is also falsified by the frequent reporting by observers of features not contained in the stimulus letter.

Discrimination Learning↗
PubMed1983

Resource allocation and the attentional demands of letter encoding.

The idea that familiar events can be encoded automatically has gained general acceptance in cognitive psychology since Posner and Boies (1971) first reported that reaction times to a secondary probe were not interfered with by letter encoding. More recently, Ogden, Martin, and Paap (1981) used a more valid control for estimating baseline probe performance and found secondary task interference, suggesting that letter encoding does require attentional resources. The present series of experiments began with the aim of evaluating Ogden et al's evidence against automaticity when the first letter was not terminated after a brief exposure, as was done in their study. In the first set of experiments we found evidence of encoding interference when the interval between the two letters was varied (50 to 1,000 msec), but this interference disappeared when there was a constant 1,000-msec interval between the letters. On the basis of these findings, we hypothesized that changes in the primary task (e.g., the exposure duration of the first letter or the interval between the two letters) may influence the momentary allocation of resources between the primary and secondary tasks. More specifically, we hypothesized that any momentary reduction in the resources demanded by the primary tasks results in a reallocation of resources to the secondary task, which in turn reduces the sensitivity of the secondary task to the demands of the primary task, that is, probe performance is moved into the data-limited region of processing (Norman & Bobrow, 1975). This idea was tested by reducing resource allocation to the probe task at the time of encoding by reducing the expectancy (i.e., the probability) of probes in the temporal proximity of the first letter. The results showed that this manipulation produced a large and significant increase in encoding interference. Moreover, when the intensity of the tone (probe) was decreased from 70 to 60 dB, the magnitude of encoding interference was further increased. In regard to the specific issue of automaticity, the findings suggest that encoding familiar events does require resources, which will result in secondary task interference given that the secondary task is in the resource-limited region of processing. More important, the findings suggest that the magnitude of secondary task interference is dependent on within-trial changes in resource allocation between the primary and secondary tasks. This possibility has general implications for dual-task methodology and the measurement of attentional demands.

Adult↗
PubMed2003

Groups perform better than the best individuals on letters-to-numbers problems: informative equations and effective strategies.

One-hundred 3-person groups and 300 individuals solved 2 letters-to-numbers problems, requiring identification of the coding of 10 letters to 10 numbers by proposing an equation in letters, receiving the answer in letters, proposing a hypothesis, and receiving feedback on the hypothesis on each trial. There were 5 instruction conditions: (a). standard, (b). use at least 3 letters on all equations, (c). use at least 4 letters on all equations, (d). number 1 known before beginning problem, and (e). number 9 known before beginning problem. The groups had fewer trials to solution, proposed more complex equations, and identified more letters per equation than the best individuals. Performance was best under instructions to use at least 4 letters and with the number 9 known.

Cooperative Behavior↗
PubMed2005

Trade-offs in detecting letters and comprehending text.

Critics of the letter detection task have questioned whether findings from that paradigm reflect normal reading processes. The present study addresses these questions using a new computerized version of the letter detection task in which reading rate along with letter detection and comprehension accuracy are examined. Previous letter detection findings were replicated with this new computerized task. Different conditions were compared in which detection and comprehension instructions were manipulated as well as the salience of the target letters. The requirement to comprehend had small effects on letter detection accuracy and reading rate, and letter detection only modestly reduced comprehension. Thus, the procedures developed in this study permit examination of the component processes contributing to performance in the letter detection task.

Adolescent↗
PubMed2006

A survey of general dental practitioners' opinions of response letters received from hospital specialists following a referred patient's first appointment.

OBJECTIVES: To discover what dentists require of a hospital response letter with regards to content and timeliness. DESIGN: Postal survey. SETTING: South Wales. SUBJECTS AND METHODS: A postal questionnaire was issued to all dentists (n = 256) who had referred a patient to the dental hospital between 1 January 2003 and 1 March 2003. RESULTS: The response rate was 60.2% (154). The preferred time frame for the receipt of a letter following a patient's appointment was one to three weeks for 96.4% (n = 133) of respondents, but 58.4% believed that they currently do not receive responses within this time frame. The preferred method of communication remained the letter (n = 82, 53%), followed by the telephone (n = 58, 38%). E-mail accounted for eight percent (n = 12) of communication. Most respondents (70%, n = 107) were satisfied with the letters' content. Eight of the ten items of information suggested as being appropriate in a response letter were considered essential by 53.2% of dentists (n = 82), and 55.8% (n = 76) believed the remaining two items to be desirable. CONCLUSIONS: Dentists agree closely on the information required in a response letter and most are satisfied with the content of current response letters. However, many dentists believe response letters arrive later than three weeks after their patient's appointment.

Correspondence as Topic↗
PubMed1999

Improving the letters we write: an exploration of doctor-doctor communication in cancer care.

Referral and reply letters are common means by which doctors exchange information pertinent to patient care. Twenty-eight semi-structured interviews were conducted exploring the views of oncologists, referring surgeons and general practitioners. Twenty-seven categories of information in referral letters and 32 in reply letters after a consultation were defined. The letters to and from six medical oncologists relating to 20 consecutive new patients were copied, and their content analysed. Oncologists, surgeons and general practitioners Australia wide were surveyed using questionnaires developed on data obtained above. Only four of 27 categories of referral information appear regularly (in > 50%) in referral letters. Oncologists want most to receive information regarding the patient's medical status, the involvement of other doctors, and any special considerations. Referring surgeons and family doctors identified delay in receiving the consultant's reply letter as of greatest concern, and insufficient detail as relatively common problems. Reply letters include more information regarding patient history/background than the recipients would like. Referring surgeons and family doctors want information regarding the proposed treatment, expected outcomes, and any psychosocial concerns, yet these items are often omitted. Consultants and referring doctors need to review, and modify their letter writing practices.

Correspondence as Topic↗
PubMed2004

The effect of hypertension and hypercholesterolemia screening with subsequent intervention letter on the use of blood pressure and lipid lowering drugs.

AIM: To evaluate the effect of a letter intervention that was send to both the participants of a population screening and their general practitioners. We also tested what predicting variables influenced the GP to actually prescribe blood pressure lowering drugs (BPLD) or lipid lowering drugs (LLD). METHOD: The study design was cross sectional, in the PREVEND outpatient clinic in Groningen University Hospital, the Netherlands. We used the clinical data of the 8592 subjects that participated in the first screening of the PREVEND study. Data on drug use was collected from community pharmacies. Drug use was measured the year before and after the screening with the subsequent intervention letter. As control population without intervention, we used the data from the InterAction DataBase (IADB) standardized for the population characteristics of the intervention group. The letter intervention was sent to participants who had shown after screening to have either an elevated blood pressure or plasma cholesterol, and the letter contained the advice to use a BPLD or LLD. Main outcome measures were proportion of patients prescribed BPLD and/or LLD in the year before and after the intervention, and variables that influence the GP to prescribe BPLD and LLD. RESULTS: Data from the community pharmacy were available from 7567 (88%) subjects. 397 participants (5.2%) received a letter with advice to start a BPLD, and 326 participants (4.3%) received a letter with advice to start a LLD. The prevalence of patients who were using BPLD and LLD before the intervention was not significantly different between the intervention and control group, 16.6 (CI 95% 15.8 -17.5) vs 16.0 and 4.8 (4.4-5.3) vs 4.6, respectively. After the letter intervention, the prevalence of BPLD use was higher in the intervention group compared with the control group (19.4 [18, 5-20, 3]vs 17.0%), as was the prevalence of LLD use (7.1[6.5-7.7) vs 5.4%). The same held true for the incidence of BPLD (3.4[3.0-3.8]vs 2.5%) and LLD use (2.1 [1, 6-2, 4]vs 1.0%), respectively, in the year after the intervention. Univariate and multivariate analysis showed that a higher blood pressure and cholesterol level, but not the presence of other cardiovascular risk factors, were associated to with a greater percentage use of a BPLD and a LLD. CONCLUSION: A population survey followed by a letter of intervention to both the patient and GP are effective to improve the use of blood pressure and lipid lowering drugs as a primary prevention in patients with hypertension and hyperlipidemia. Our therapeutic advice however, was followed only in about one of the three subjects with hypertension and one of the four subjects with hyperlipidemia. The levels of blood pressure and plasma total cholesterol are important variables influencing the GP to prescribe a BPLD and/or LLD.

Adult↗
PubMed2002

[Patient countersigned referral letters in schizophrenic disorders].

OBJECTIVE: Our aim was to discuss referral letters with psychotic patients and to assess patients views about this proceeding and about the letters. Also patients knowledge of their diagnosis was assessed. METHODS: The day after discussing the letter 80 patients were evaluated with a short questionnaire. RESULTS: 92 % of patients responded very positively to the discussion of the referral letter. Many patients appreciated the transparency and information and stated, that it improved the understanding of the illness and the doctor-patient-relationship. The day of hospital discharge 96 % of patients were able to name the exact diagnosis or an adequate replacement. CONCLUSIONS: Our results show, that the majority of psychotic patients - in contrast to previous experiences - responded very favourably to the referral letters, probably because they not only received the letter but also discussed the letter with their doctor and had the opportunity to correct false details before discharge. The encouragement of communication, the acceptance of patients as equal partners and the improvement of information, empower patients as active partners in care, which improves the course of the disease. Therefore patients should have the possibility to discuss the referral letter with their doctor.

Adaptation, Psychological↗
PubMed1997

Visual perception of motor anticipation in cursive handwriting: influence of spatial and movement information on the prediction of forthcoming letters.

The execution of a graphemic sequence is constrained by spatial demands that result in fluctuations of letter shape and movement time. When producing two letters (ll, le, or ln) the movement time and the letter shape of the first letter depend on the execution constraints of the second one. The motor system thus anticipates the production of the forthcoming graphemic sequence during the production of the first letter. An experiment is reported the aim of which was to examine whether the visual system could exploit this anticipatory information to predict the identity of the letter following the l. Different ls belonging to ll, le, and ln were presented on a screen. Subjects had to predict to which couple of letters (ll, le, or ln) the presented l belonged to, by using information on the shape of the l and/or the movement that produced it. Results showed that the percentages of correct responses were higher in the conditions where the stimulus provided kinematic information than in the condition in which only spatial information was available. The ability to predict the forthcoming letter seems to be mediated by implicit knowledge on motor anticipation rules.

Adult↗
PubMed1990

Representation of letters when mislocation errors occur.

Errors in reporting a cued target letter appearing among a string of letters more often reflect the mislocation of a letter appearing elsewhere in the string than the intrusion of one not in the string. The current experiment was conducted to determine the representation of letters at the stage at which errors occur. Four letters (from a set of 12 chosen to contain counterpart pairs that were similar physically, phonemically, or both physically and phonemically) appeared in each exposure, with the target letter indicated by a cue in the postexposure mask. Letter strings presented to one group of subjects were flanked on either side by a pound sign (#) to assess the effect of lateral masking on the terminal letter in the string. Physical similarity dictated the pattern of mislocations between counterparts, suggesting a physical rather than phonemic or abstract representation. Lateral masking played no significant role in the difference between intrusions and mislocations.

Attention↗