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PubMed1995

[A case of metamorphopsia restricted to faces and different familiar objects].

The case of a 19-year old patient suffering of transient metamorphopsia restricted to familiar faces and familiar objects is reported. This clinical sign resulted from a small right occipitotemporal haemorrhage due to a sub-cortical metastasis. The patient claimed that faces are distorted and look more pleasant. There were neither visual field defects nor visual agnosia. MRI revealed a small high signal area in the right fusiform gyrus. The structural and functional aspects of the metamorphopsia are documented and discussed in relation to aperceptive prosopagnosia. More specifically, it is suggested that facial metamorphopsia and aperceptive prosopagnosia express the same underlying disorder differing only in terms of severity.

Adult↗
PubMed1997

Distortions of time in the transference: some clinical and theoretical implications.

The author considers that patients' distortions of time can frequently and readily be observed in clinical psychoanalysis, reflecting both their psychopathology and their reactions to the temporal aspects of the psychoanalytic setting. These phenomena are considered in order to examine the assumptions that can implicitly be made about the nature of space and time in object-relations theory. Two case histories are given to exemplify these clinical phenomena-the first being an example of a fixation and the second one of a psychic retreat. These cases are compared to demonstrate the unconscious processes underlying the particular time distortions being considered, their impact on the patient's lives and their manifestation in the clinical setting. On the basis of these studies, it is suggested that the asymmetry of the 'arrow of time' cannot be assumed in the structure of psychic reality. The clinical evidence suggests that psychic reality has to be seen as discontinuous and that the structure of the discontinuities is revealed by the impact that the temporal aspects of the psychoanalytic setting have on the patient.

Humans↗
PubMed2003

Eph receptor deficiencies lead to altered cochlear function.

Ephrins and Eph receptors are a family of molecules that have been implicated in many developmental processes including neuronal network formation, guidance of cell migration, and axonal pathfinding. These molecules exhibit the ability to send bidirectional signals following ligand-receptor interactions resulting from cell-cell contacts. Gene-targeted knockout mice of B-class ephrins and Eph receptors have been shown to display phenotypic responses that correlate with anatomical defects. For example, disruption of the EphB2 receptor leads to defects of the vestibular system, including pathfinding abnormalities in efferent axons and reduced endolymph production. Such developmental distortions lead to deficiencies in ionic homeostasis and repetitive circling behaviors. The present study demonstrates that B-class ephrins and Eph receptors are expressed in cochlear tissues, suggesting that they may play some role in auditory function. To determine whether ephrins and Eph receptors have a functional role in the peripheral auditory system, distortion-product otoacoustic emission (DPOAE) levels, collected across a broad frequency range, were compared between groups of mice expressing different Eph receptor genotypes. In particular, EphB1 and EphB3 receptor knockout mice exhibited significantly diminished DPOAE levels as compared to wild-type littermates, indicating that these specific Eph receptors are necessary for normal cochlear function.

Aging↗
PubMed1996

Comparison of two computer animated imaging programs for quantifying facial profile preference.

To establish the physical basis of subjective judgements of facial appearance, two novel computer-imaging programs differing in method of preparation and presentation of 5 features of the facial soft-tissue profile of 4 faces representing 4 different classifications of dental occlusion were compared. Images of facial soft tissue of 5 features were digitized and "animated" from 16 discrete distortions or morphed from the two extremes of each feature. 12 volunteer judges responded to both the "animated" and morphed presentations by pressing the computer mouse button when the image became acceptable and releasing the button when the image was no longer acceptable. They also pressed the mouse button when the most pleasing distortion appeared from either direction. Aggregating responses to counterbalanced trials and features across judges yielded high correlations between the programs for midpoint of acceptability. Although both programs provide reliable and valid measures of subjective acceptability of present and proposed changes in facial morphology, the new morphing program is more user-friendly than the "animated" method.

Adult↗
PubMed2004

Assessment of auditory function in rhesus monkeys (Macaca mulatta): effects of age and calorie restriction.

Age-related alterations in auditory function were evaluated in adult male rhesus monkeys (Macaca mulatta) involved in a long-term study evaluating the effects of caloric restriction (CR) on aging. We assessed 26 monkeys in a control group fed a low fat, high fiber diet at approximately ad libitum levels and 24 monkeys in a CR group that were fed the same diet reduced in amount by 30% compared to age- and weight-matched controls. The following measures of auditory function were obtained while monkeys were maintained under anesthesia: (1) distortion product otoacoustic emissions (DPOAEs); (2) auditory brainstem responses (ABRs); and (3) middle latency responses (MLRs). All DPOAE measures and peak II amplitude significantly decreased with age, while peak IV latency and ABR threshold significantly increased with age. We found no significant effects of CR on any auditory parameters examined.

Aging↗
PubMed2002

Deficits of spatial working memory in chronic schizophrenia.

This study tests the hypothesis that deficits of spatial working memory are an inherent trait in schizophrenic patients, regardless of their clinical status. The participants were 22 chronic schizophrenic patients, 11 schizophrenic patients in remission, and 22 normal adults. All participants were asked to track the outlines of a square presented on a computer screen in a clockwise direction while moving their eyes at their preferred rate and then to reproduce the square on a blank computer screen (Task A). Thereafter, the computer only displayed the four corners of the same square. The corners were displayed sequentially in a clockwise direction, one at a time at equal intervals. They were asked first to track the four corners of the square and then to reproduce the square on a blank computer screen (Task B). Chronic schizophrenic patients reproduced tasks A and B with significantly greater distortions than normal controls. The extent of their distortions was significantly greater during the reproduction of Task A than Task B. By contrast, schizophrenic patients in remission reproduced both Tasks A and B with the same accuracy as normal controls. On the basis of these findings it is concluded that the chronic schizophrenic patients have a significant deficit of spatial working memory, but that this deficit can be ameliorated by cognitive interventions and is therefore not an immutable trait in schizophrenia.

Adult↗
PubMed1986

Effect of ecological viewing conditions on the Ames' distorted room illusion.

Ecological theory asserts that the Ames' distorted room illusion (DRI) occurs as a result of the artificial restriction of information pickup. According to Gibson (1966, 1979), the illusion is eliminated when binocular vision and/or head movement are allowed. In Experiment 1, to measure the DRI, we used a size-matching technique employing discs placed within an Ames' distorted room. One hundred forty-four subjects viewed the distorted room or a control apparatus under four different viewing conditions (i.e., restricted or unrestricted head movement), using monocular and binocular vision. In Experiment 2, subjects viewed binocularly and were instructed to move freely while making judgments. Overall, the main findings of this study were that the DRI decreased with increases in viewing access and that the DRI persisted under all viewing conditions. The persistence of the illusion was felt to contradict Gibson's position.

Adult↗
PubMed2002

Adaptation of handwriting size under distorted visual feedback in patients with Parkinson's disease and elderly and young controls.

OBJECTIVE: The ability to use visual feedback to control handwriting size was compared in patients with Parkinson's disease (PD), elderly people, and young adults to better understand factors playing a part in parkinsonian micrographia. METHODS: The participants wrote sequences of eight cursive l loops with visual target sizes of 0.5 and 2 cm on a flat panel display digitiser which both recorded and displayed the pen movements. In the pre-exposure and postexposure conditions, the display digitiser showed the actual pen trace in real time and real size. In the distortion exposure conditions, the gain of the vertical dimension of the visual feedback was either reduced to 70% or enlarged to 140%. RESULTS: The young controls showed a gradual visuomotor adaptation that compensated for the visual feedback distortions during the exposure conditions. They also showed significant after effects during the postexposure conditions. The elderly controls marginally corrected for the size distortions and showed small after effects. The patients with PD, however, showed no trial by trial adaptations or after effects but instead, a progressive amplification of the distortion effect in each individual trial. CONCLUSION: The young controls used visual feedback to update their visuomotor map. The elderly controls seemed to make little use of visual feedback. The patients with Parkinson's disease rely on the visual feedback of previous or of ongoing strokes to programme subsequent strokes. This recursive feedback may play a part in the progressive reductions in handwriting size found in parkinsonian micrographia.

Aged↗
PubMedDate not supplied

Disordered recognition and perception of human faces in acute schizophrenia and experimental psychosis.

Three disorders of facial recognition and perception in acute schizophrenia and mescaline-induced psychosis are described and illustrated using original clinical and experimental material: "affective prosopagnosia" or stress-related dysfunctional face recognition; "physiognomization" of the environment or persistent illusions and hallucinations of nonspecific faces; and the "mirror phenomenon" or the experience of inner alienation from one's reflected face, which is perceived as independently alive, sinister, and generally physically distorted. It is proposed that neuropsychology suggests relationships between these phenomena that might otherwise be less apparent. No final neurobiological solution to the problem of dysfunctional facial perception and recognition in psychosis is presented, but various insights and suggestive models from the neurosciences are discussed. Attention is also paid to the conditions under which one might need to combine neuropsychological approaches with hermeneutically oriented analyses.

Acute Disease↗
PubMed2004

Relation between cognitive distortions and neurobehavior disinhibition on the development of substance use during adolescence and substance use disorder by young adulthood: a prospective study.

OBJECTIVE: Previous research has demonstrated that neurobehavior disinhibition increases the risk for a diagnosis of substance use disorder (SUD). This investigation tested the hypothesis that a deficiency in the capacity to appraise the effects of alcohol and drugs and interpret social interactions mediates the relation between neurobehavior disinhibition in childhood and SUD by early adulthood. METHODS: Boys with fathers having lifetime SUD (N=88) and no SUD or other psychiatric disorder (N=127) were prospectively tracked from ages 10-12 to 19 years. Neurobehavior disinhibition was evaluated at baseline followed by assessments of cognitive distortions and substance use involvement in early and mid-adolescence. SUD outcome was evaluated up to age 19 years. RESULTS: Cognitive distortions (age 12-14 years) mediated the association between neurobehavior disinhibition (age 10-12 years) and marijuana use (age 16 years) which, in turn, predicted SUD by age 19 years. Cognitive distortions in early adolescence did not directly predict SUD by young adulthood. CONCLUSIONS: Inaccurate social cognition, significantly predicted by childhood neurobehavior disinhibition, biases development toward marijuana use prodromal to SUD. These results indicate that cognitive processes, in conjunction with psychological self-regulation, comprise important components of the individual liability to SUD.

Adolescent↗
PubMed1989

[Experiences with the distorted Freiburg Speech Test--diagnosis and rehabilitation of hearing disorders].

In accordance with the description of an extended technique of distorted speech at different values - 15 dB, - 10 dB, - 5 dB and 0 dB with the plotted frequency characteristic, we used the procedure with different kinds of sensorineural hearing loss. The method analyse the peripheral hearing system very simply. In cases of acoustic tumours the quotient is very large and it is better to reduce the degree of distortion (-10, -5 and 0 dB). Generally, it is possible to detect the phase of degeneration of the inner hair-cells and afferent nerve fibres in all cases of sensorineural hearing loss. The test is also of very good help in fitting hearing aids because method picks out the hard hearing persons with very disturbed discrimination of speech.

Adult↗
PubMed1981

Identification of local and propagating distortion products from cochlear microphonic responses.

Careful measurements show that sound pressures of 40 dB re 20 mu N/m2 are sufficient to reveal two varieties of well-behaved, nonlinear distortion products in the cochlear microphonic (CM). The first variety appears in the primary-tone area and is designated as a local CM distortion product. The second type exists apical to the primary-tone area and is identical to the mechanically propagated distortion seen in the phase-locked responses of primary auditory nerve fibers. The existence of the propagating distortion product forces the conclusion that there must be a mechanical contribution to the local "CM" distortion product as well. The intrusion of nonlinear mechanical responses at such low levels (less than 40 dB SPL) indicates that the effective mechanical input to the hair cells may be nonlinear over most of the audible range. An important but unanswered question is the range over which the transducer characteristic of CM could be effectively linear, for that would determine whether CM could be used to probe mechanical nonlinear effects in the primary tone area.

Acoustic Stimulation↗
PubMed1997

Comparison of cognitive style in bulimia nervosa and depression.

This study investigated the global and specific cognitive style associated with bulimia nervosa. Three groups of women (women with bulimia nervosa, women with major depression, and controls) completed measures of eating disorder severity, depression, dysfunctional cognitions and irrational beliefs. The control group was found to report significantly lower levels of cognitive distortions and irrational beliefs overall than both women with bulimia nervosa and women with depression. However, no difference was found between the latter two groups. Furthermore, the pattern of individual cognitions and beliefs was exactly the same. When depression was statistically controlled, cognitive style no longer differentiated between the control group and two clinical groups. These results have implications for improving the effectiveness of cognitive behaviour therapy for bulimia nervosa.

Adolescent↗
PubMed1997

Sorority women's body size perceptions and their weight-related attitudes and behaviors.

Six hundred twenty-seven sorority women were surveyed to determine if sorority members constituted a subgroup of college women who may be at increased risk for disordered eating. The sorority members were administered Body Mass Index Silhouettes and the Eating Disorder Inventory. The findings indicated that these sorority women may have a greater fear of becoming fat, are more dissatisfied with their bodies, and are more weight preoccupied and concerned with dieting than are college women from previous studies. The findings also suggested that body size perceptions were distorted among both underweight and overweight women and that thin was the ideal body profile for the majority of the women. Although bulimia scores were higher for this population than for those reported in all but one of the previous studies, these differences were not significant. More research and innovative programs designed to address weight-related attitudes and behaviors among this population are called for.

Adolescent↗
PubMed1978

Hypnosis and related clinical behavior.

The essential aspect in the experience of the hypnotized person is the altered or distorted perception that is suggested to him. Not all people are capable of the experience, but it is possible that spontaneous distortions occur in those with high hypnotizability. These distortions are frequently experienced as frightening symptoms. The author draws attention to the similarity between hysterical symptoms and events in hypnosis and to the high hypnotic responsivity in hysterical subjects reported in the clinical literature of the nineteenth century. Phobic patients have relatively high hypnotic responsivity. The author believes that it is sometimes possible to predict hypnotizability from clinical behavior, and that hypnotic responsivity can be utilized in psychodynamically sensitive therapy to teach such patients that they can learn to gain control of their symptoms.

Adult↗
PubMed1989

Assessment of facial self-image by means of a distorting mirror and its relationship to personality.

A flexible distorting mirror was used to give a distorted image of volunteers, who then attempted to alter the mirror to give a true reflection of their faces. Their accuracy in performing this task was correlated with age, sex, extroversion, neuroticism and also with total body and facial self-image as obtained from questionnaires. On average, subjects could not accurately define the size of their faces to within 5 cm, and the higher the body image score on the questionnaire, the less well subjects performed on the flexible mirror.

Adolescent↗
PubMed2000

Characterization of hearing in an X,0 'Turner mouse'.

Turner's syndrome is due to total (45,X) or partial (mosaicism) loss of one X-chromosome. The main features are short stature, ovarian dysgenesis with no estrogen production and infertility. In addition to ear and hearing disorders, middle ear problems including acute/serous otitis media and chronic middle ear disease are frequent. Sensorineural hearing loss is often seen with a dip in the mid-frequencies and also an early high frequency loss. In this study, middle-and inner-ear pathology was characterized using physiological and morphological techniques in a 'Turner mouse' that has been generated with the chromosomal aberration X,0. Otitis media was found in some of these X,0 animals, a symptom that is seldom found in control animals. The auditory brainstem responses (ABR) of the Turner mouse showed a progressive hearing loss in the high frequency region that exceeded the normal age-related hearing loss of control mice and increased latencies of the first ABR wave. Outer hair cell loss was apparent in the cochlear basal turn of Turner mice. Decreases in the amplitude of distortion product otoacoustic emissions were correlated with the loss of ABR threshold sensitivity. These results indicate that hearing problems in the Turner mouse seems to be of cochlear origin with an eighth nerve component. This Turner mouse model appears to have ear and hearing problems quite similar to humans and can therefore be used as a model to determine the auditory pathology underlying this syndrome.

Animals↗
PubMed2002

Magnetic oscillatory responses to lateralization changes of natural and artificial sounds in humans.

Oscillatory signals in human magnetoencephalogram were investigated as correlates of cortical network activity in response to sound lateralization changes. Previously, we found lateralized presentations of a monosyllabic word to elicit posterior temporo-parietal gamma-band activity, possibly reflecting synchronization of neuronal assemblies in putative auditory dorsal stream areas. In addition, beta activity was decreased over sensorimotor regions, suggesting the activation of motor networks involved in orientating. The present study investigated responses to lateralization changes of both a barking dog sound and a distorted noise to test whether beta desynchronization would depend on the sound's relevance for orientating. Eighteen adults listened passively to 900 samples of each sound in separate location mismatch paradigms with midline standards and both right- and left-lateralized deviants. Lateralized distorted noises were accompanied by enhanced spectral amplitude at 58-73 Hz over right temporo-parietal cortex. Left-lateralized barking dog sounds elicited right and right-lateralized sounds elicited bilateral temporo-parietal spectral amplitude increases at approximately 77 Hz. This replicated the involvement of posterior temporo-parietal areas in auditory spatial processing. Only barking dog sounds, but not distorted noises, gave rise to 30 Hz desynchronization over contralateral sensorimotor areas, parieto-frontal gamma coherence increases and beta coherence reductions between sensorimotor and prefrontal sensors. Apparently passive listening to lateralized natural sounds with a potential biological relevance led to an activation of motor networks involved in the automatic preparation for orientating. Parieto-frontal coherence increases may reflect enhanced coupling of networks involved in the integration of auditory spatial and motor processes.

Acoustic Stimulation↗