Grover C Gilmore

• PhD, Psychology, Johns Hopkins
• Case Western Reserve University

BACKGROUND Cognitive assessment employing tangible objects can measure fine-motor and hand-eye coordination skills along with other cognitive domains. Administering such tests is often expensive, labor-intensive, and error-prone due to manual recording and the potential subjectivity. Automating the administration and scoring process can address the...

Background: Cognitive assessment using tangible objects can measure fine motor and hand-eye coordination skills along with other cognitive domains. Administering such tests is often expensive, labor-intensive, and error prone owing to manual recording and potential subjectivity. Automating the administration and scoring processes can address these...

Background Deficits in basic vision are associated with visual hallucinations in Parkinson's disease. Of particular interest is contrast sensitivity loss in this disorder and its effect on object identification. Objectives Evaluate whether increased contrast improves object perception in persons with Parkinson's disease and visual hallucinations,...

This article summarizes the presentations and recommendations of the tenth annual American Geriatrics Society and National Institute on Aging Bench‐to‐Bedside research conference, “Sensory Impairment and Cognitive Decline,” on October 2–3, 2017, in Bethesda, Maryland. The risk of impairment in hearing, vision, and other senses increases with age, a...

Responding to David Stoesz’s invited article criticizing the Children’s Bureau and the National Child Welfare Workforce Institute (NCWWI), the author’s inaccurate assertions are challenged, and new information is provided about the significant work underway to support the child welfare workforce. The Children’s Bureau has made historic investments...

Recent evidence indicates that sensory and motor changes may precede the cognitive symptoms of Alzheimer's disease (AD) by several years and may signify increased risk of developing AD. Traditionally, sensory and motor dysfunctions in aging and AD have been studied separately. To ascertain the evidence supporting the relationship between age-relate...

Conceptualized by social work deans and actualized with the support of major social work organizations, the American Academy of Social Work and Social Welfare was established in 2009. This article describes the historical context and creation of the Academy, whose objectives include recognizing outstanding social work scholars and practitioners; in...

Contrast sensitivity functions were measured in elderly and young persons for sinusoidal gratings that reversed phase by 180° at rates of 0.3 and 6.3 Hz. Elderly subjects showed less sensitivity than young subjects for spatial frequencies. Their sensitivity to high spatial frequencies declined faster as the rate of reversal increased. These changes...

We examined performance of healthy older and younger adults and individuals with Alzheimer's disease (AD) and Parkinson's disease (PD) on digit cancellation, a task putatively sensitive to cognitive impairment, but possibly affected by visual impairment, particularly in contrast sensitivity. Critical contrast thresholds were established to create c...

External support may improve task performance regardless of an individual's ability to compensate for cognitive deficits through internally generated mechanisms. We investigated if performance of a complex, familiar visual search task (the game of bingo) could be enhanced in groups with suboptimal vision by providing external support through manipu...

As psychological instruments are converted for administration on computers, differences in luminance and contrast of these displays may affect performance. Specifically, high-luminance assessments may mask age-group differences that are apparent under lower luminance conditions. We examined the effects of luminance and contrast on object detection...

Visual perceptual problems are common in Parkinson's disease (PD) and often affect activities of daily living (ADLs). PD patients with non-tremor symptoms at disease onset (i.e., rigidity, bradykinesia, gait disturbance or postural instability) have more diffuse neurobiological abnormalities and report worse non-motor symptoms and functional change...

Deficits in visual cognition in Alzheimer's disease (AD) arise from neuropathological changes in higher-order association areas of the cortex and from defective input from lower-level visual processing areas. We investigated whether enhanced signal strength may lead to improvement of visual cognition in AD. We tested 35 individuals with probable AD...

Multiple forms of a symbol-digit substitution task were used to provide a componential analysis of age differences in coding task performance. The results demonstrated age differences in feature encoding, memory, and visual search. A 2nd experiment was conducted with young adults to investigate a sensory deficit as a locus of age differences. The s...

The oral word reading speed of patients with Alzheimer's disease (AD) and healthy young and older control participants was evaluated across a broad range of stimulus contrast levels in two experiments. The impact of stimulus repetition on reading speed also was examined. It was found that the older adult participants, and particularly the AD patien...

Deficient perception and cognition in Alzheimer's disease (AD) has been attributed to slow information processing and attentional disturbance, but an additional explanation may be reduced signal strength. In 21 individuals with probable AD, 29 healthy older and 54 younger adults, we enhanced the contrast level of rapidly-flashed masked letters. The...

This chapter addresses the hypothesis that Alzheimer’s disease (AD) involves a deficit in the magnocellular pathway of the visual system. Evidence from the neuroanatomical, neurophysiological, and psychophysical literatures that assesses the magnocellular deficit hypothesis is reviewed. A meta-analysis of the studies on coherent motion perception i...

Substitution tests have a long history in psychology because of their simplicity of administration and their sensitivity to individual differences related to complex cognitive performance. Despite their widespread use there is no agreement on what the substitution test measures. The present study approached this question by applying a method of com...

Deficient perception and cognition in Parkinson's disease (PD) has been attributed to slow information processing, but an alternative explanation may be reduced signal strength. In 18 nondemented individuals with PD and 15 healthy adults, we enhanced the contrast level of rapidly flashed masked letters. The PD group required significantly higher co...

Young and older adults were tested in both a letter-identification and a letter-matching task in which the integrity of the letter stimuli was manipulated through contrast reduction and low-pass spatial frequency filtering. The use of the contrast and filtering manipulations was an attempt to increase encoding difficulty in an effort to examine whe...

Young and older adults were tested in both a letter-identification and a letter-matching task in which the integrity of the letter stimuli was manipulated through contrast reduction and low-pass spatial frequency filtering. The use of the contrast and filtering manipulations was an attempt to increase encoding difficulty in an effort to examine whe...

We developed an adaptive forced-choice method whereby reference and test presentations were alternated in order to minimize effects from variables such as subject attention level. In our demonstration example of an X-ray fluoroscopy perception study, we measured detectability of low-contrast objects in noisy image sequences and determined X-ray dos...

In this study, we tested the hypothesis that low smooth pursuit gain in schizophrenia is related to an abnormality in motion perception. The subjects were 19 schizophrenics treated with clozapine and 19 controls. In addition to smooth pursuit and motion perception paradigms, sustained attention was also assessed using a continuous performance task...

Studies conducted at our Alzheimer Center in Cleveland, Ohio, along with those of other investigators, have documented that visual hallucinations occur with sufficient frequency in Alzheimer's disease and related dementias to warrant further investigation of their meaning and implications. The largest data set in which frequency of hallucinations a...

Examined the hypothesis that the reading speed deficit often experienced by Alzheimer's disease (AD) patients could be modified through contrast enhancement. 10 AD patients (mean age 71.5 yrs), 10 nondemented elderly (mean age 67.1 yrs), and 10 young adults (mean age 18.8 yrs) were asked to identify briefly presented letters. The stimuli were shown...

The chapter discusses the studies that are stimulated by the observation that Alzheimer's disease (AD) patients experience a marked decline in contrast sensitivity. The decline is attributed to deficiencies of signal processing, especially within the M-cell channels. It is speculated that such an elementary deficit may be linked to the poor perform...

Spatial contrast sensitivity was evaluated in normal elderly adults and a group with probable Alzheimer's disease (AD) in three sessions over a 1-year period. There was evidence of a reduction over 1 year in contrast sensitivity for static, high spatial frequencies in both groups of subjects. A striking difference between the subject groups was obs...

Spatial contrast sensitivity was evaluated in normal elderly adults and a group with probable Alzheimer's disease (AD) in three sessions over a 1-year period. There was evidence of a reduction over 1 year in contrast sensitivity for static, high spatial frequencies in both groups of subjects. A striking difference between the subject groups was obs...

The motion sensitivity of 15 probable alzheimer disease (AD) patients and 15 healthy elderly adults was investigated with a correlated motion paradigm. The AD patients exhibited significantly higher thresholds for detecting the direction of motion. Contrast sensitivity for a 2 cpd, 7.5 Hz counterphased stimulus was related to motion threshold in th...

Pulsed fluoroscopy (hereafter called pulsed) at reduced acquisition rates, typically 15 acq/s (pulsed‐15), is proposed to reduce x‐ray dose in interventional procedures. However, since the human visual system (HVS) acts as a temporal low‐pass filter that interacts with such acquisitions, the proper dose for pulsed must be obtained in perception exp...

Eight models are examined as input-output representations of steady-state vision in humans at moderate to low level illumination. Three new models for visual contrast sensitivity are introduced and evaluated using contrast sensitivity function (CSF) data with samples on both narrow and wide frequency ranges. Additionally, five variations of previou...

Schizophrenic and control subjects were tested on two-flash fusion (TFF) and visual backward masking (VBM) tasks in a repeated measures design. Each subject was tested in a single session. Both tasks used the same equipment and stimuli. There was no difference between the groups in their ability to detect the presence of two separate stimuli in the...

The authors used a correlated motion paradigm to investigate the effects of aging and gender on motion sensitivity. In 2 experiments with a total of 50 elderly and 50 young subjects, motion thresholds were significantly higher for elderly women. The correlated motion signal, which was embedded in random motion, may have been coherent to subjects in...

X-ray fluoroscopy is a significant source of x-ray dose to patients and hospital staff. One technique proposed for reducing dose is pulsed fluoroscopy at reduced frame rates, typically 15 frames/sec for cardiac angiography. Because the human visual system acts as a temporal low-pass filter, simply reducing the frame rate may not allow a dose reduct...

The present study was designed to compare the contrast sensitivity functions (CSF) obtained with the Nicolet CS2000 and the Vistech VCTS6500 for a sample (N = 25) of patients diagnosed with probable Alzheimer's disease (AD) and a sample (N = 25) of healthy elderly adults. With the Nicolet, CSF were determined for gratings presented under static and...

The sensitivity of the neural channels which process spatial frequency information may be assessed by determining the threshold contrast for a range of spatial frequencies. The stability and reliability of two methods of assessment, von Bekesy tracking and increasing contrast, were examined over 4 sessions with a sample of 12 young and 12 elderly a...

A subgroup of patients with Alzheimer's disease (AD) developed Balint's syndrome, an uncommon and incompletely understood disorder of visuospatial processing. We characterized the visuospatial features of three AD patients with Balint's syndrome and compared them to three comparably demented AD patients without this syndrome. On visuospatial tasks,...

Several different scaling techniques, i.e., Borg category (BC) and visual analogue (VA) scales have been used to quantitate the intensity of the respiratory sensations elicited during exercise, but their relationship is unclear. Six subjects with stable chronic obstructive lung disease (FEV1 = 1.2 +/- 0.1 SE L) simultaneously rated the sense of eff...

A nonverbal auditory test of sustained attention was administered to 20 young and 20 elderly women, screened to ensure good health. Groups were matched for intelligence. Older subjects performed as accurately as younger subjects. Neither group showed increases in response latency as a function of time spent on test. Older subjects took longer to re...

Previous attempts to measure the capacity of iconic memory in elderly adults have been unsuccessful, demonstrating in one case that 80% of the elderly adults tested could not perform above chance level. The present experiments illustrated that the partial report paradigm designed by Sperling (1960) could be used with elderly adults to obtain such a...

It Has Been Argued That Principles of Perceptual Organization Play An Important Role In The Representation of A Visual Stimulus And That Elderly Adults May Be Deficient In Perceptual Unit Formation. The Present Study Examined The Extent To Which The Gestalt Principles of Grouping By Proximity And Similarity Predicted The Formation of Large Perceptu...

Detections of appearances and disappearances in briefly interrupted complex patterns were examined in young and old subjects. According to neurophysiological evidence developed by Singer and Phillips (1974), the detection rates for the two types of events, which differ substantially as pattern durations and interstimulus intervals vary, are attribu...

Administered block designs that varied according to two parameters, Task Uncertainty and Perceptual Cohensiveness, to 83 persons 49 years of age or older. Performance was adjusted to remove motor speed differences. Performance changed significantly over the age span as a function of Task Uncertainty. From 49 years up, performance did not change as...

Neurophysiological and psychophysical evidence indicates that the visual system performs a sort of Fourier analysis of retinal variations in brightness through multiple spatial frequency-tuned channels. Two types of applications of techniques of two-dimensional Fourier analysis are discussed: (1) modeling and simulation of visual functions, and (2)...

The application of two-dimensional Fourier analysis provides new avenues for research in visual perception. This tutorial serves as an introduction to some of the methods used in two-dimensional Fourier analysis and an introduction to two-dimensional image processing in general.

A decline in performance on the Digit Symbol Substitution test related to aging is well documented. There is no agreement on the reason for the decline, however. In part, the lack of consensus with regard to changes on the test may be attributed to the limitations imposed by comparing groups on a single performance measure. In the present study, th...

A medical illustrator uses visual aids to communicate with other medical professionals and with the lay public. These visual aids are designed and executed in such a way that others can better perceive and understand difficult concepts and procedures. Because medical illustrations reflect a subjective interpretation of reality, it is important to a...

Administered three forms of a Symbol-Digit Substitution task to normals, 16 to over 80 years of age, to schizophrenic and other hospitalized groups. Their data are presented for normative purposes. The three forms vary in difficulty and provide a measure of visual information processing ability, Clinical and research implications of the data are di...

Three experiments were conducted to examine the influence of non-target letters on target detection performance. It was hypothesised that letters which are similar would exert a stronger masking influence on each other than letters which have a low level of feature similarity. The results indicate, however, that every letter has the same inhibitory...

• A report of numerosity task was used in 2 experiments to examine the effect of inherent stimulus organization on the report accuracy of 2 S groups. Ss in each experiment were 10 schizophrenics and 10 drug abusing inpatients (controls). In both experiments, displays containing from zero to 6 lines were presented tachistoscopically. In Exp I, the l...

A report of numerosity task was used in 2 experiments to examine the effect of inherent stimulus organization on the report accuracy of 2 S groups. Ss in each experiment were 10 schizophrenics and 10 drug abusing inpatients (controls). In both experiments, displays containing from zero to 6 lines were presented tachistoscopically. In Exp I, the lin...

In order to provide a reliable measure of the similarity of uppercase English letters, a confusion matrix based on 1,200 presentations of each letter was established. To facilitate an analysis of the perceived structural characteristics, the confusion matrix was decomposed according to Luce’s choice model into a symmetrical similarity matrix and a...

The influences of presentation mode (mixed vs. blocked trials) and target variability on the detection of targets in words and in random letter strings were examined. The results indicated that there was a substantial word superiority effect in mixed lists of words and nonwords, but that this effect was eliminated when pure lists of words and nonwo...