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At least 235 records · Page 13Linked to original sources

Word deafness and auditory cortical function. A case history and hypothesis.

A patient who already had Wernicke's aphasia due to a left temporal lobe lesion suffered a severe deterioration specifically of auditory language comprehension, subsequent to right temporal lobe infarction. A detailed comparison of his new condition with his language status before the second stroke revealed that the newly acquired deficit was limited to tasks related to auditory input. Further investigations demonstrated a speech perceptual disorder, which we analysed as due to deficits both at the level of general auditory processes and at the level of phonetic analysis. We discuss some arguments related to hemisphere specialization of phonetic processing and to the disconnection explanation of word deafness that support the hypothesis of word deafness being generally caused by mixed deficits.

Aphasia, Wernicke↗

The perceptual consequences of visual loss: 'positive' pathologies of vision.

Fifty patients with visual hallucinations and illusions secondary to degenerative eye disease reported remarkably stereotyped experiences. Questionnaire responses revealed five previously recognized categories of pathological vision (perseveration, illusory visual spread, polyopia, prosopometamorphopsia and micro/macropsia) and three novel categories (tessellopsia, hyperchromatopsia and dendropsia). Identical pathologies of vision occur in a range of clinical and experimental settings, suggesting that they reflect fundamental visual processes. The known neurophysiology of the visual cortex helps explain the phenomenology of the experiences and provides the basis for a neurobiologically based classification of positive and negative visual perceptual disorders.

Eye Diseases↗

Emotional responses to unpleasant music correlates with damage to the parahippocampal cortex.

Music is typically a pleasurable experience. But under certain circumstances, music can also be unpleasant, for example, when a young child randomly hits piano keys. Such unpleasant musical experiences have been shown to activate a network of brain structures involved in emotion, mostly located in the medial temporal lobe: the parahippocampal gyrus, amygdala, hippocampus and temporal pole. However, the differential roles of these regions remain largely unknown. In this study, pleasant and unpleasant music was presented to 17 patients with variable excisions of the medial temporal lobe, as well as to 19 matched controls. The pleasant music corresponded to happy and sad selections taken from the classical instrumental repertoire; the unpleasant music was the dissonant arrangement of the same selections. Only patients with substantial resections of the left or right parahippocampal cortex (PHC) gave highly abnormal judgements to dissonant music; they rated dissonant music as slightly pleasant while controls found it unpleasant. This indifference to dissonance was correlated with the remaining volume in the PHC, but was unrelated to the volume of the surrounding structures. The impairment was specific: the same patients judged consonant music to be pleasant, and were able to judge music as happy or sad. Furthermore, this lack of responsiveness to unpleasantness was not due to a perceptual disorder, because all patients were able to detect intentional errors in the musical excerpts. Moreover, the impairment differed from that induced by amygdala damage alone. These findings are consistent with a two-dimensional model of defensive responses to aversive stimuli, in which the PHC and the amygdala subserve different roles.

Adult↗

Psychophysical studies on the binocular processes of amblyopes.

It has frequently been assumed that humans with abnormal binocular vision resulting from amblyopia or strabismus lack binocular cortical neurons. From this assumption, it would be predicted that amblyopes would fail to show binocular interactions on any psychophysical tasks. This paper describes some recent psychophysical experiments investigating the binocular processes of amblyopes. The results of these experiments have shown that most humans with abnormal binocular vision fail to show binocular interactions for psychophysical tasks such as stereopsis or binocular summation, but show partially normal binocular interactions for interocular transfer of visual aftereffects and show normal interactions for dichoptic masking with grating stimuli.

Amblyopia↗

Are cochlear implant patients suffering from perceptual dissonance?

Cochlear implants provide functional hearing to the majority of recipients and have gained widespread acceptance clinically, but the range of performance remains great and largely unexplained. Designs for implanted electrodes and electronics have converged, whereas novel speech processing strategies have proliferated. For each patient, the fitting audiologist must sort empirically through options that produce large but idiosyncratic differences in both objective performance and subjective preference. This review and analysis suggests that the place-pitch and rate-pitch theories on which cochlear implants have been designed are incomplete. The missing component may be related to the phase-locking of auditory nerve activity to both acoustic and electrical stimulation. This component is likely to be highly distorted by electrical stimulation but its importance as one of several different pitch encoding mechanisms may vary widely among patients. Systematic means to control these putative phase effects using modern, high-speed, and high-density cochlear implants may make it possible to identify more efficiently the best strategy for a given patient and to minimize the perceptual confusion that arises from conflicting cues.

Acoustic Stimulation↗

The meaning of basic symptoms for the genesis of the schizophrenic nuclear syndrome.

In the Bonn Transition Sequences study, the development of the Schneiderian first rank symptoms in their exact chronological order was studied from the first symptomatological precursors up to the complete forms of the respective psychotic final phenomena. At their onset, subjective experiences of preexisting disorders of perception, thinking, speech and memory, of cognitive control of action and of proprioception were found. These four groups of initial deficiencies developed via certain intermediate phenomena into first rank symptoms. The analysis of these transition sequences revealed three phases with different generating factors each. Altogether, the results showed that and how the gap between the deficiency findings of the biologically oriented research in schizophrenia and the diagnostically relevant changes in experience can be bridged.

Adolescent↗

Aura phenomena and psychopathology: a pilot investigation.

We investigated a possible relation between aura phenomena and psychopathology in patients with seizure disorders. Twenty-one patients with a variety of seizure types (90% with generalized seizures, 72% with complex partial seizures, CPS) were studied. Aura phenomena were evaluated with the Silberman-Post Psychosensory Phenomena Scale; psychopathology was assessed with the Schedule for Affective Disorders and Schizophrenia-Lifetime Version (SADS-L), the Minnesota Multiple Personality Inventory (MMPI), and the Washington Psychosocial Seizure Inventory (WPSI). Psychosensory symptoms occurring in the absence of frank seizures, but not those occurring with seizures, were related to increased psychopathology (primarily mood and anxiety related) and greater time in psychiatric treatment. Psychosensory symptoms may reflect ongoing neurophysiologic dysfunction related to epilepsy and may therefore be a useful subject for further study.

Adaptation, Psychological↗

Clinical predictors of course and outcome in delusional psychosis.

The purpose of the study was to examine whether clinical variables of first-admitted patients with delusional psychosis were of predictive importance of course and outcome illuminated through the dimensions: psychotic symptoms, impairment, remission, and relapse at 2-year follow-up. Male, sex, age below 30 years, unmarried, long duration of psychosis, and absence of psychosocial stress prior to first admission were all statistically predictive of poor outcome. Concerning nonspecific psychological distress high mean values on the subscales of helplessness-hopelessness, dread and antisocial history were correlated to poor outcome as was low mean value of active expression of hostility. Concerning psychopathology assessed by PSE individual items as lost emotions, thought insertion, thought broadcast, primary delusions and certain auditory hallucinations (voices discussing/commenting subject in third person) predicted poor outcome. Further classes of PSE symptoms as perceptual disorder, thought disorder, and delusions of influence predicted poor outcome too. Other prognostic unfavourable variables were systematisation of delusions, severe preoccupation with present delusions and no suspicion of attempt at concealment of delusions and hallucinations.

Adolescent↗

A multivariate predictor analysis of course and outcome in delusional psychosis.

The purpose of the study was to examine whether certain social variables of first-admitted patients with delusional psychosis were of predictive value of course and outcome as illuminated through the dimensions: psychiatric symptoms, impairment, remission, and relapse at 2-year follow-up. Furthermore, the aim was to perform a multivariate analysis of the most informative clinical and social predictors of course and outcome. Several predictors were significantly associated with at least one of the dimensions of poor outcome. In the multivariate logistic analysis an independent significant effect was assigned to male sex, no work, no evasiveness of delusions, perceptual disorder, preoccupation with delusions, dread, and few social contacts. The most informative clinical and social predictors yielded a maximal information of 27% to 47% for the different dimensions of course and outcome. One fifth of the patients had good outcome. This was significantly predicted by the following variables: married, living with others, frequent social contacts, high social group, full time work, clouding, delusions of guilt, and attempt at concealment of delusions and hallucinations, yielding a maximal information of 41%. Frequent social contacts and delusions of guilt had an independent statistical effect on good outcome. It is concluded that good prognosis is exceptional in patients with delusional psychosis and not combined to a single nosological unit. The findings stress the need for a specific investigation of the prognostic importance of social intervention and community care in patients with delusional psychosis.

Adolescent↗

The role of the Child Health Services in the identification of children with possible attention deficit hyperactivity disorder/deficits in attention, motor control and perception (ADHD/DAMP).

Literature concerning the role of the Child Health Services in the identification of children with possible Attention Deficit Hyperactivity Disorder/Deficits in Attention, Motor Control and Perception (ADHD/DAMP) is summarized in order to establish a background for evaluation, discussion and conclusion.

Attention Deficit Disorder with Hyperactivity↗