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PubMed1979

Implementation of the problem-oriented progress note in a skilled nursing facility.

Problem-oriented style progress notes were implemented in a skilled nursing facility where problem-oriented medical records were not in use. The problem-oriented note consists of subjective information, objective information, analysis or assessment of the problems, and plan for treatment, and is called a SOAP note. Six physical and occupational therapists used the method of note writing for an eight-week trial period. The author audited the records for errors in using the SOAP note throughout the experimental period. Therapists responded to a questionnaire following the study to assess their attitudes on using the SOAP note. Implementation of the problem-oriented progress note was satisfactory, with the exception of defining the problem list. The therapists reacted positively toward using the problem-oriented method of recording patient progress or status and recommended that its use be taught to physical and occupational therapy students.

Evaluation Studies as Topic↗
PubMed1995

Interocular suppression in cat striate cortex is not orientation selective.

For the majority of neurones in cat striate cortex, the response to an optimal stimulus presented to one eye is suppressed when a stimulus of substantially different orientation is presented to the other eye. In order to determine the true orientational tuning of the underlying inhibitory interactions in the absence of binocular facilitation for matched stimuli, we tested how the response of such cells to an optimal grating in one eye is affected by gratings in the other eye of spatial frequencies too high or low to elicit an excitatory response through either eye: the vast majority of cells displayed suppression that was essentially independent of orientation. Our results indicate that interocular inhibition derives from cells representing all orientations, but is swamped by interocular facilitation for stimuli matched in orientation and spatial frequency.

Animals↗
PubMed1997

Visual working memory for shape and 3D-orientation: a PET study.

In order to determine the neural substrate of working memory for shape and 3D-orientation, regional cerebral blood flow (rCBF) changes were estimated using positron emission tomography (PET). Subjects were scanned during the performance of two delayed-matching-to-sample tasks using flat polydedrical objects of different shapes and 3D-orientations presented in a virtual environment. The shape matching task was associated with activation in the occipito-temporal junction, occipito-parietal cortex and mesial frontal pole of the right hemisphere. During the orientation matching task, rCBF increased in the mesial occipito-temporal cortex, superior temporal gyrus and middle frontal gyrus of the left hemisphere. The right supramarginal gyrus was also activated. These results suggest that both visual pathways are engaged in the processing of objects presented in different orientations. The dorsal stream is involved mainly in working memory of 3D-orientation, while the ventral stream is involved especially in shape working memory.

Adult↗
PubMed1997

Orientation-dependent binocular interactions in area 21a of the cat.

We investigated binocular interactions in area 21a cells of the anaesthetized cat. Visual stimuli were drifting sinusoidal gratings presented at the same optimal orientation in each eye (iso-oriented condition) or at the optimal orientation in the dominant eye and the orthogonal orientation in the other eye (orthogonal condition). In 68% of cells the response in the binocular iso-oriented condition was greater than the dominant eye monocular response, while in 88% of cells the response in the binocular orthogonal condition was less than the dominant eye monocular response. Our results suggest a possible role for this extrastriate region of cortex in binocular contour rivalry.

Animals↗
PubMed1994

Visual impairment in Parkinson's disease: deficits in orientation and motion discrimination.

PURPOSE: In order to obtain a better understanding of the pathophysiology of visual impairment in Parkinson's disease (PD), orientation and motion discrimination were investigated in PD patients. METHODS: Orientation and motion discrimination thresholds were assessed psychophysically in PD patients with normal cognition (N = 11) and compared to results for age-matched controls (N = 22). RESULTS: PD patients exhibited a significant deficit in orientation discrimination for horizontal but not for vertical gratings. Also, motion discrimination thresholds were elevated significantly in PD patients. No significant correlations were found between motion and orientation discrimination thresholds. CONCLUSIONS: Our results indicate that PD patients exhibit significant visual dysfunction in the absence of cognitive impairment supporting the contention that neural dysfunction in PD is more generalized than previously realized. The results provide further evidence of an orientation selective visual deficit in PD and show that the ability to discriminate global motion is also attenuated in PD.

Aged↗
PubMed2001

Does mobility performance of visually impaired adults improve immediately after orientation and mobility training?

BACKGROUND: Previous studies that have attempted to determine the effect of orientation and mobility training on mobility performance of visually impaired adults have had a number of limitations. With the inclusion of a control group of subjects, this study investigated the effect of orientation and mobility training on mobility performance of a group of visually impaired adults. METHODS: Vision was measured binocularly as high- and low-contrast visual acuity, letter and edge contrast sensitivity, and Humphrey kinetic visual fields. The subjects' mobility performance was assessed as percentage preferred walking speed (PPWS) and error score before and after mobility training. RESULTS: Orientation and mobility training did not enhance mobility performance compared with the control group, who did not receive training, when performance was measured immediately after training. PPWS improved for both groups with short-term practice only, but there was no improvement in error score due to either practice or training. CONCLUSIONS: There was no immediate improvement in mobility performance of visually impaired adults after orientation and mobility training. Familiarity with the route may play an important role in measured improvement of mobility performance after orientation and mobility training.

Adaptation, Ocular↗
PubMed2004

Postnatal binge ethanol exposure affects habituation of the cardiac orienting response to an olfactory stimulus in preweanling rats.

BACKGROUND: Prenatal exposure to alcohol can result in intellectual impairments, reduced habituation and distractibility, visual-spatial deficits, and problems in attention. Dysfunction in attention, including habituation of responses to nonsignal stimuli, can have devastating consequences for cognitive development. This research examined whether binge exposure to ethanol on postnatal days (PD) 4 to 9 would affect cardiac orienting or response habituation to an olfactory stimulus in preweanling rats. METHODS: Ethanol-exposed subjects were given ethanol 5.25 g/kg/day on PD4 to 9. Controls were either sham intubated or unhandled during this time. To assess baseline and phasic cardiac function, PD16 subjects were tested under differential pharmacological blockade of the sympathetic or parasympathetic nervous systems by administration of the peripherally acting antagonists atenolol or atropine methyl nitrate. In a second experiment, separate groups of subjects were tested for habituation of the cardiac orienting response to an olfactory stimulus. RESULTS: Results indicate that postnatal ethanol had no observable effect on the functional development of autonomic control over heart rate. Similarly, ethanol exposure had no effect on the form or magnitude of the cardiac orienting response. However, neonatal ethanol exposure did result in a deficit in orienting response habituation; ethanol-exposed subjects continued to respond to the stimulus with a large-magnitude bradycardia after control subjects exhibited complete response habituation. In addition, ethanol-exposed subjects had longer orienting response latencies than controls. CONCLUSIONS: The results indicate that this animal model has the potential to contribute to investigations designed to understand basic forms of memory impairments observed in humans with a history of prenatal alcohol exposure. The postnatal binge ethanol model of fetal alcohol effects produces deficits in nonassociative memory that are similar to those observed in human infants exposed prenatally to ethanol. Deficits in response habituation have important implications for cognitive development.

Animals↗
PubMed2005

Reference frame and haptic discrimination of orientations in infants.

Body-tilt effect on the haptic discrimination of orientations and the 'oblique effect' (better discrimination of the vertical orientation than of an oblique orientation) were examined in 5-month-old infants. Body tilt leads to a mismatch between egocentric and gravitational reference frames and indicates in which reference frame orientations and oblique effect are defined. A familiarization/reaction to novelty procedure was used in upright body and tilted body conditions. Results revealed the occurrence of a haptic oblique effect in the upright body position, which disappeared when the body was tilted. The results suggest that spatial orientations and the oblique effect depend on a mixed reference frame that integrates not only gravitational information but also egocentric information.

Analysis of Variance↗
PubMed1983

The distribution of wavelength and orientation selective cells in different areas of monkey visual cortex.

The distribution of orientation and wavelength selective cells in visual areas V1, the V4 complex and V5 of macaque monkey cortex was studied by recording from regions representing equivalent eccentricities in each and characterizing cells for their orientational and wavelength preferences. The results showed: (a) that in V1 wavelength selective cells are concentrated in the region of foveal representation (central 0-2 degrees) and decline at increasing eccentricities; (b) that in the V4 complex the concentration of such cells does not vary with eccentricity; rather, there are regional variations that are not eccentricity dependent but follow other, and unknown, rules; (c) that in V5 there are virtually no wavelength selective cells even at central eccentricities; (d) that in V1 fewer than 50% of cells with receptive fields in the central 0-2 degrees are orientation selective and that the proportion of such cells increases to reach a high of about 80% at eccentricities of between 10 and 30 degrees; (e) that in the V4 complex and in V5 the concentration of orientation selective cells decreases at increasing eccentricities; (f) that very few wavelength selective cells in V1 and in the V4 complex are orientation selective. The implications of these findings for a comparison between visual areas of the monkey cortex are discussed.

Animals↗
PubMed1996

Orientation discrimination is impaired in the absence of the striate cortical contribution to human vision.

We have examined visual discrimination of orientation for bars and edges presented to the 'blind' hemifield of a patient, GY, who has an extensive lesion involving the left striate and prestriate cortex. The patient's residual vision in response to transient light stimulation of his 'blind' hemifield has been well characterized, and it provides discrimination on the basis of differences in target velocity, flicker frequency or colour. We now show that using his residual vision, GY can identify accurately the orientation of a flickering bar, although his performance is sub-normal for bars shorter than 10 deg. He is, however, unable to identify the orientation of a one-dimensional grating presented within a circular aperture, and is unable to detect a grating structure formed by equiluminant coloured bars or by alternating, equiluminant flickering and steady bars. We also show that he has poor orientation discrimination for edges formed by colour contrast, by contrast between moving stimuli or by flicker contrast. We conclude that in the absence of the striate cortical input, the residual mechanisms which provide discriminations for colour, flicker or movement are not well organized for the detection and discrimination of stimulus orientation. We discuss the physiological mechanisms responsible for the various aspects of GY's residual vision.

Adult↗
PubMed1982

Neural systems control of spatial orienting.

A peripheral visual cue in an empty field (1) often summons head or eyes, or both, (2) improves efficiency at the cued position while attention is directed to it, even without overt movements, and (3) reduces processing efficiency at the cued position once attention is withdrawn. We have studied the time course and the effects of mid-brain and cortical damage on these components of orienting. The facilitation arises from shifts in covert attention. In cases of mid-brain degeneration due to progressive supranuclear palsy, saccadic movements were abolished, while covert orienting still occurs. However, covert orienting was found to be delayed in directions in which eye movements were most affected, suggesting a role for mid-brain pathways in covert orienting. Parietal lesions can cause massive loss in detection contralateral to the lesion. This is especially true when attention has been directed to the opposite side. These findings relate aspects of covert orienting of attention to neural control systems.

Attention↗
PubMed2004

Amygdala central nucleus function is necessary for learning but not expression of conditioned visual orienting.

When exposed to pairings of a visual stimulus with food delivery, rats normally acquire both conditioned orienting responses directed toward the visual stimulus and conditioned food-related responses. Consistent with the results of previous lesion studies, reversible inactivation of amygdala central nucleus function before each conditioning session prevented the acquisition of conditioned orienting responses, whereas food-related behaviors were acquired normally. By contrast, neither inactivation nor neurotoxic lesions of central nucleus affected the expression of previously acquired conditioned orienting responses. Thus, the central nucleus is apparently not critical to the maintenance of information required for conditioned orienting, but instead is necessary for memory storage elsewhere. Specialized roles for components of a circuit for conditioned orienting, which includes the central nucleus, the substantia nigra, and dorsolateral striatum, are discussed.

Amygdala↗
PubMed1998

Detecting the orientation of short lines in the periphery.

PURPOSE: Visual information processing in the human cortex is based on a highly ordered representation of the surrounding world. In addition to the retinotopic mapping of the visual field, systematic variations of the orientation tuning of neurons have been described in the primary visual cortex. As a step to understanding the relationship between position and orientation representation, we investigated psychophysically the minimum spatial requirements for the determination of orientation at various positions across the visual field. We know that the shortest line whose orientation can be resolved varies with eccentricity, such that its length corresponds to slightly less than 0.2 mm projected onto the cortical surface. Along the horizontal meridian horizontal lines are detected with higher precision than vertical or oblique lines. In the present experiments, we tested whether this is a preference for horizontal lines or for lines that are orientated radially away from the fovea. METHODS: Human observers were tested with lines positioned at one vertical, two horizontal and two oblique meridians at eccentricities between 5 and 25 degrees. RESULTS/CONCLUSION: Three of the four subjects were most sensitive for targets aligned with the meridian of presentation. This suggests that the visual system has the highest resolution in directions radiating from the fovea, which may be particularly useful for the analysis of flow fields resulting from forward translation.

Humans↗
PubMed1993

Effects of visual cortex lesions on orientation discrimination of illusory contours in the cat.

We have trained five cats in orientation discrimination using different contours, and compared the deficits caused by lesions of cortical areas 17 and 18 (tier I) to the deficits induced by removal of those areas receiving afferents originating in areas 17 and 18 (tier II). As contour stimuli we used two types of illusory contours and a luminance bar. The two illusory contours were defined by opposed line-ends. One of them coincided with a luminance gradient whereas the other did not. Tier I lesions destroyed the capacity to discriminate the orientation of both illusory contours, and also caused an important, though less severe, deficit in bar orientation discrimination. The deficits induced by tier I lesions were permanent. Tier II lesions also caused significant deficits in orientation discrimination of illusory contours, but only a negligible deficit in bar orientation discrimination, and this result was not a mere consequence of a difference in difficulty between the tasks involving bars and illusory contours. In addition, tier II lesions differentiated between illusory contour types, the deficit being more pronounced for the illusory contour without luminance gradient than for the one with luminance gradient. In contrast to tier I lesions, tier II lesions allowed significant recovery, leading to small final deficits for all contour types tested.

Animals↗
PubMed2006

Cholinergic modulation of response properties and orientation tuning of neurons in primary visual cortex of anaesthetized Marmoset monkeys.

Cortical processing is strongly influenced by the actions of neuromodulators such as acetylcholine (ACh). Early studies in anaesthetized cats argued that acetylcholine can cause a sharpening of orientation tuning functions and an improvement of the signal-to-noise ratio (SNR) of neuronal responses in primary visual cortex (V1). Recent in vitro studies have demonstrated that acetylcholine reduces the efficacy of feedback and intracortical connections via the activation of muscarinic receptors, and increases the efficacy of feed-forward connections via the activation of nicotinic receptors. If orientation tuning is mediated or enhanced by intracortical connections, high levels of acetylcholine should diminish orientation tuning. Here we investigate the effects of acetylcholine on orientation tuning and neuronal responsiveness in anaesthetized marmoset monkeys. We found that acetylcholine caused a broadening of the orientation tuning in the majority of cells, while tuning functions became sharper in only a minority of cells. Moreover, acetylcholine generally facilitated neuronal responses, but neither improved signal-to-noise ratio, nor reduced trial-to-trial firing rate variance systematically. Acetylcholine did however, reduce variability of spike occurrences within spike trains. We discuss these findings in the context of dynamic control of feed-forward and lateral/feedback connectivity by acetylcholine.

Acetylcholine↗
PubMed1991

The relationship between skin conductance orienting and the allocation of processing resources.

Information processing models of autonomic orienting suggest that the elicitation of an orienting response is associated with either the call for, or the actual allocation of, limited attentional processing resources. However, Dawson, Filion, and Schell (1989) reported a directional dissociation between elicitation of the skin conductance orienting response and resource allocation, as indexed by reaction time slowing on a secondary task. Although larger skin conductance responses were elicited by a task-relevant stimulus than by a task-irrelevant stimulus, reaction time showed the opposite pattern (i.e., greater slowing to secondary task probes presented shortly following the onset of the task-irrelevant stimulus). In the present report, we describe three experiments which examine the generality of this dissociation effect and test specific hypotheses regarding its nature. Results of the first two experiments revealed that the dissociation effect is observed reliably when the task-relevant and task-irrelevant stimuli consist of left ear and right ear tones or high and low pitched binaural tones, across a range of secondary task probe presentation times. However, the third experiment demonstrated that when task-relevant and task-irrelevant stimuli are presented to different sensory modalities (auditory and visual), orienting and resource allocation are both greater during the task-relevant than the task-irrelevant stimuli, thus eliminating the dissociation effect. These results support the hypothesis that the dissociation effect is due to a switch of attention initiated because of the physical similarity of the task-relevant and task-irrelevant stimuli, and suggest that there is a fundamentally positive relationship between skin conductance orienting and resource allocation under selective attention conditions.

Adult↗
PubMed1994

Probing the orienting response with startle modification and secondary reaction time.

Current models of orienting suggest a relationship between the orienting response and attentional processing. This relationship was examined using two independent probe techniques to index attentional processing: secondary reaction time and startle eyeblink modification. Twenty-eight college-age subjects received intermixed presentations of to-be-attended and to-be-ignored tones. Skin conductance orienting responses were obtained during a subset of the tones. Each of the remaining tones contained either a secondary reaction time probe at lead intervals of 150 or 2,000 ms or a startle eyeblink probe presented at lead intervals of 120 or 2,000 ms. In addition, reaction time and startle probes also were presented during selected intertone intervals, and responses to these stimuli served as the baselines from which to compare changes in reaction time and blink amplitude produced by the attended and ignored tones. The results revealed that, compared with the ignored tones, the attended tones were associated with larger skin conductance orienting responses, greater blink inhibition at the 120-ms lead interval, greater blink facilitation at the 2,000-ms lead interval, and greater reaction time slowing at the 2,000-ms lead interval. Consistent with previous findings, the ignored tone was associated with greater reaction time slowing than was the attended tone at the 150-ms lead interval. The results support a relationship between elicitation of the skin conductance orienting response and attentional processes and suggest that the secondary reaction time and blink modification techniques may provide unique information regarding this relationship.

Acoustic Stimulation↗
PubMed2006

A review of the literature on orientation as an indicator of level of consciousness.

PURPOSE: To review and compare the concepts of orientation and level of consciousness. METHODS: Literature review, including studies of orientation as an indicator of level of consciousness, in the domains of nursing, medicine, and neuropsychology. FINDINGS: Orientation to time, place, and person as a measure of level of consciousness is poorly understood. The nursing practice of assessing orientation is common in many practice settings, yet little research has been done to validate whether it is meaningful. CONCLUSIONS: This review lays important groundwork for future evidence-based research into the use of orientation as an indicator of level of consciousness.

Consciousness↗