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At least 19 recordsLinked to original sources
PubMed1976

The Honi phenomenon revisited: factors underlying the resistance to perceptual distortion of one's partner.

An individual being viewed in an Ames room usually appears considerably altered in physical size to an observer. However, some married persons perceive less size distortion of their spouses than a stranger. This instance of selective perceptual distortion, known as the Honi phenomenon, could perhaps reflect differential familiarity and/or emotional involvement toward these stimulus persons. Using heterosexual couples as subjects, we investigated familiarity (i.e., length of the relationship), type of relationship (i.e., dating, engaged, or married), and positive cathexis (i.e., love, liking, and trust of one's partner) as possible mediators of this effect and also explored the impact of some judgemental variations. Neither familiarity nor type of relationship influenced relative perceptual distortion of partner versus stranger. Rather, selective perceptual distortion was directly related to the strength of positive cathexis, principally among females. Only women high in positive cathexis exhibited the Honi phenomenon and perceived a stranger as being more distorted than their partners. In contrast, size judgements by men were affected only by the sequence in which stimulus persons were observed. Implications and interpretations of these findings are discussed.

Awareness↗
PubMedDate not supplied

Cognitive and perceptual distortions in borderline personality disorder and schizotypal personality disorder in a vignette sample.

Clinical vignettes of patients with borderline personality disorder (BPD) and schizotypal personality disorder (STPD) were evaluated and rated for evidence of cognitive and perceptual distortions. The differences in the distortions of each group were then compared. The findings show that while STPD patients have significantly more cognitive and perceptual distortions than borderlines, there is an abundance of such distortions in the borderline group. The borderline group may differ, moreover, in that their cognitive and perceptual distortions were found to be significantly more object-related than those of the schizotypal group.

Borderline Personality Disorder↗
PubMed1992

Preliminary observations concerning treatment of visual discomfort and associated perceptual distortion.

A system for therapeutic precision tinting is described. Some individuals who are subject to perceptual distortion of text no longer perceive the distortion when the text has a particular colour. A simple colorimeter enables an observer to illuminate text with light of a particular chromaticity, varying first CIE 1976 hue angle (huv), then saturation (suv), and then luminance, to obtain a setting that maximizes visual comfort and reduces any perceptual distortion. The colorimeter setting is then matched by a combination of tinted trial lenses. The combination uses only two dyes at a time from a selection of seven, unless a dark lens is required, when a third neutral (grey) dye is added. The subject observes both text and a normal scene when wearing tinted trial lenses. A variety of trial lenses are compared including those that match the colorimeter setting and others with similar hue angle. Spectacle lenses are then tinted so as to have a spectral transmission identical to that of the chosen combination of trial lenses. Certain patients with reading disorders, eye-strain, headaches or photosensitivity epilepsy report benefit when wearing spectacles tinted according to the above techniques. The physiological basis for the therapeutic effects is uncertain, but may involve a selective impairment of luminance or colour-difference channels.

Adolescent↗
PubMed1992

Pregenital fixation and perceptual distortions to conflict-laden material.

Three standard questionnaire measures of oral and anal fixation were administered to 142 students. On the basis of their scores 26 students were selected and shown tachistoscopic exposures of pictures designed to activate oral or anal conflicts. Five subjects in each group had extremely high scores on the corresponding measure of fixation, five had extremely low scores, and 16 had intermediate scores. It was hypothesised that individuals who were fixated at one or other of the psychosexual stages would show stereotyped perceptual distortions to repeated dim exposures of the corresponding picture. Highly fixated subjects showed significantly more deviant responses than did subjects who showed low levels of fixation at the same stage. A form of Q-factor analysis indicated that subjects who were fixated at the oral sadistic or anal stages showed different patterns of perceptual distortions to the anal picture than those who were not fixated. These results were interpreted as supporting the link between defenses against anal eroticism and the anal character.

Adult↗
PubMed1992

Colorimeter for the intuitive manipulation of hue and saturation and its role in the study of perceptual distortion.

A simple optical method for mixing coloured light is described. The observer has intuitive and approximately independent control over hue and saturation at constant brightness. The method facilitates colour matching by unpracticed observers. It allows children with reading difficulties to select a colour that reduces perceptual distortion of text. The chromaticity coordinates of this colour vary from one observer to another but can be very specific. Complementary colours can exacerbate the distortions and induce pain. For the majority of children reporting beneficial perceptual effects, the u' coordinate is less than 0.25.

Adolescent↗
PubMed1977

Perceptual distortion of body image in adolescent girls: distortion of body image in adolescence.

Body image estimations in 86 normal-weight adolescent girls showed (a) a tendency to overestimate body width and underestimate body length and (b) an association between the younger ages and the extent of overestimation of body width. In particular there is a sharp drop in overestimation between ages 10 and 11 and thereafter a more gradual and non-significant decline. These age-specific normative data are useful in assessing body image distortions in a variety of medical and psychiatric disorders.

Adolescent↗
PubMed1978

Global hemianaesthesia: a parietal perceptual distortion suggesting non-organic illness.

In two patients, lesions in the non-dominant parietal lobe were associated with global anaesthesia to all sensory modalities affecting the opposite half of the body. A striking inconsistency existed between the complaints of limb anaesthesia and the grossly preserved motor and postural control of the involved limb. The gross discrepancy between complaint and functional ability prompted early consideration of a "non-organic" diagnosis. It is suggested that this unusual sensory deficit may be due to distorted perception of somatosensory stimuli, representing another disorder of body schema associated with parietal lobe lesions. The diagnosis of non-organic illness may then be avoided by focusing on a search for parietal disease.

Adolescent↗
PubMed1991

A Newtonian model of perceptual distortion in visuo-spatial neglect.

We propose a simple mathematical model that describes how unilateral brain damage distorts the representation of length in two-dimensional space. The model was tested on eighteen normal adults and six patients with left visuo-spatial neglect after right hemisphere lesion. The subjects bisected lines at eight orientations from vertical to horizontal and the displacement of their transections from true centre was expressed as a function of inclination. Although accuracy differed considerably from patient to patient, sinusoidal functions of the predicted form were found in all cases. The pattern of distortion is an exaggeration of one subtype of normal performance, and is fully consistent with the hypothesis that the cerebral hemispheres have antagonistic attentional biases.

Aged↗
PubMed1992

Fearful distortions.

Clinical observations suggesting that perceptual distortions can take place during episodes of fear are described, and two hypotheses are set out: (1) perceptual distortions occur during episodes of fear, and (2) such distortions decline after reduction of the pertinent fear. An experiment in which fearful subjects were asked to report their perceptions of a feared object during episodes of fear, and then again after fear-reduction, was carried out. Snake-phobic and spider-phobic subjects showed evidence of some distortions in the activity of the pertinent fear object, but no distortions of size. After the reduction of the relevant fear, the subjects reported significant declines in the activity of the pertinent animal. The two hypotheses received partial support.

Adult↗
PubMed1977

Social aspects of body image: perception of normalcy of weight and affect of college undergraduates.

Two aspects of body image, perception of normalcy of weight and affect, were studied by means of a paper-and-pencil test with 62 male and 117 female undergraduates. The relationship of the social characteristics of sex, age, race, and actual body weight (underweight, normal weight, overweight) to body-image distortion was investigated. Individuals who were underweight or overweight were more likely to perceptually distort their weight-related appearance than were normal weight respondents. Among those who misperceived their weight-related appearance, both underweight and overweight persons tended to normalize their appearance. Among those who misperceived their weight-related appearance, sex was also related to the type of perceptual distortion experienced. Females tended to perceive themselves as appearing heavier, whereas males tended to perveive themselves as appearing lighter, than they actually were. There was no relationship between perceptual distortion of body weight and body affect. Age, race, and actual body weight were related to affect. Affect was more negative among young respondents than older respondents. White individuals had poorer affect scores than non-whites. Overweight respondents also had more negative affect scores than other respondents.

Adolescent↗
PubMed1991

Dysphoria in male alcoholics with a history of hallucinations.

This paper examines severity of depressive symptoms, as measured by the Beck Depression Inventory, in chronic alcoholics with and without a history of hallucinations. We found a) alcoholics entering alcohol treatment who have experienced hallucinations during detoxification report higher levels of subjective depression than alcoholics who have never experienced hallucinations, b) the level of subjective depression in alcoholics with a history of hallucinations remains higher at the end of inpatient alcohol treatment than in alcoholics without hallucinations, and c) hallucination is the important variable; alcoholics with blackouts, seizures, and delirium tremens, do not experience higher levels of depression during detoxification. The reporting of a significantly higher level of depressive symptoms by alcoholics with a history of experiencing hallucinations during withdrawal suggests that in some alcoholics, there exists a vulnerability for mood abnormalities which includes a predisposition toward other abnormal mental phenomena such as perceptual distortions.

Alcoholism↗
PubMed1979

Hypnotic deafness: a psychophysical study of responses to tone intensity as modified by hypnosis.

Hypnotic deafness was suggested for 1000 Hz tones presented in random orders at seven intensities between 17 and 70 db. Subjects were 70 college students stratified into four levels of hypnotic susceptibility, ranging from low to high. Four conditions were presented within a single session. Two conditions tested normal hearing, one in waking and one in hypnosis; two tested reported loudness of the tones as reduced by hypnotic suggestion. The method of magnitude estimation was employed. Hearing reduction was found to correlate .59 with hypnotic susceptibility in the total sample. Few high hypnotizables reduced their hearing to zero; their mean residual hearing during the deafness conditions was 55% of normal. Power functions for the relationship between tone intensity and magnitude estimates for conditions of normal hearing and deafness were found to be relatively parallel and orderly, differing primarily in intercept value. Order effect anomalies are discussed. The "hidden observer" method showed that for 4 of the 70 subjects the covert hearing was found to be at least 20% greater than that reported overtly within hypnotic deafness and approached normal hearing. As in our previous hypnotic analgesia research, not all subjects who reduced their hearing significantly gave subsequent covert reports which differed from reported overt hearing. Discussion is given for evidence of two levels of information processing during hypnotically suggested perceptual distortions.

Audiometry↗
PubMed1975

Effect of speed adaptation on performance in a self-paced tracking task.

12 Ss were required to perform a self-paced tracking task designed to simulate 'hazardous' road conditions. Those 6 Ss who had previously been exposed to a simple, high-speed version of the task travelled faster and made more errors on the hazardous task than 6 control Ss who performed the hazardous task throughout the experiment. The findings supplement earlier studies of the effect of speed adaptation on the judgment of speed and suggest that, in addition to perceptual distortions, an acquired motivation for speed may be an important factor in the behaviour of drivers leaving high-speed roads.

Accidents, Traffic↗
PubMed1978

Aspects of body image perception in obese and normal-weight youngsters.

Perceptual and projective aspects of body image in obese youngsters (not in psychological treatment) and normal-weight youngsters 8-9 years of age and 12-13 years of age were investigated. The results indicate that perceptual distortions in estimating various body dimensions of oneself are primarily a function of age rather than weight status. The accuracy of estimating the weight of peers and an adult showed an association with the sex of the subject. No group differences were found in terms of projective aspects of body image as measured by barrier and penetration responses. This study suggests that obese youngsters in the middle childhood and entering puberty periods in comparison to normal-weight youngsters of the same age do not manifest differences in perceptual factors of body image.

Adolescent↗
PubMed1992

Percept-genetic signs of repression in histrionic personality disorder.

Several types of perceptual distortions of two anxiety-arousing visual stimuli are coded as repression in the Defense Mechanism Test, a tachistoscopic, percept-genetic technique. Given the well-established correspondence between hysteria and repression, the study included a clinical validation of these variants of repression against the diagnosis of histrionic personality disorder. 41 subjects with evidence of this disorder on the Millon Clinical Multiaxial Inventory-II were compared with 41 nonhistrionic controls. Significantly more histrionics were coded for the type of repression in which the threatening figure is transformed into a harmless object (code 1:42), while animal- and statue-repressions, when combined (codes 1:1 and 1:2), were significantly more characteristic of the nonhistrionic group. As an unpredicted finding, significantly more histrionic subjects employed defensive strategies, currently coded as reaction formations (code 4:). Histrionic subjects without concomitant compulsive features were coded more frequently for introaggression (code 6:) compared both with nonhistrionic controls and with histrionic-compulsive subjects. The findings are discussed within the context of the available percept-genetic literature. It is suggested that the Defense Mechanism Test may be further employed to objectify and investigate the defense mechanisms of the DSM-III-R disorders.

Adult↗
PubMed1990

Denial of separation anxiety as measured by a serial tachistoscopic technique.

A mother-child separation stimulus was repeatedly presented by standard Defense Mechanism Test procedure, at increasing durations of tachistoscopic exposure to 60 clinical and nonclinical subjects. Subjective verbal reports were coded blindly for evidence of perceptual distortions presumably indicative of denial of separation anxiety. Low scores on two items measuring sensitivity to separation anxiety and intolerance of aloneness were, as predicted, significantly more often characterized by codings of denial on the tachistoscopic exposures than subjects with high sensitivity to separation anxiety. Stability of effect became stronger when only very low and very high scores were compared for perceptual denial on the last four presentations of the series. This technique, employing other types of anxiety-evoking stimuli, may represent a reliable instrument to reveal the presence of defences toward each of the most relevant conflictual areas of the personality.

Adult↗