Visual stimulation affects the perception of voluntary leg movements during walking

When a limb is used for locomotion, patterns of afferent and efferent activity related to its own motion are present as well as visual, vestibular, and other proprioceptive information about motion of the whole body. A study is reported in which it was asked whether visual stimulation present during whole-body motion can influence the perception of the leg movements propelling the body. Subjects were tested in conditions in which the stepping movements they made were identical but the amount of body displacement relative to inertial space and to the visual surround varied. These test conditions were created by getting the subjects to walk on a rotatable platform centered inside a large, independently rotatable, optokinetic drum. In each test condition, subjects, without looking at their legs, compared, against a standard condition in which the floor and drum were both stationary, their speed of body motion, their stride length and stepping rate, the direction of their steps, and the perceived force they exerted during stepping. When visual surround motion was incompatible with the motion normally associated with the stepping movements being made, changes in apparent body motion and in the awareness of the frequency, extent, and direction of the voluntary stepping movements resulted.     

Alterations of the phonetic coding of speech sounds during repetition

One aspect of the comprehension of speech is the assignment of a phonetic representation to the sounds being heard. However, if a person listens to a meaningless syllable that is continually repeated, over time he will hear the syllable undergo a variety of changes. These changes are very systematic in character and represent alterations in the phonetic coding assigned to an unchanging sound stimulus. When the restricted nature of the changes that occur is analyzed phonetically, these changes are found to invlove a reorganization of the phones constituting the syllables and changes in a small number of distinctive features.     

Adaptation to delayed auditory feedback

Delayed auditory feedback disrupts the production of speech, causing an increase in speech duration as well as many articulatory errors. To determine whether prolonged exposure to delayed auditory feedback IDAFI leads to adaptive compensations in speech production, 10 subjects were exposed in separate experimental sessions to both incremental and constantdelay exposure conditions. Significant adaptation occurred for syntactically structured stimuli in the form of increased speaking rates. After DAF was removed, aftereffects were apparent for all stimulus types in terms of increased speech rates. A carry-over effect from the first to the second experimental session was evident as long as 29 days after the first session. The use of strategies to overcome DAF and the differences between adaptation to DAF and adaptation to visual rearrangement are discussed.     

The influence of syntactic segmentation on perceived stress

Chomsky and Halle (1968) claim that the stress and intonation of an utterance are not determined solely by physical properties of the acoustic signal but are also influenced by the syntactic organization of the utterance. Strong support for their contention has been obtained by presenting listeners with a continuously repeated string of monosyllabic words. Such sequences undergo spontaneous perceptual re-grouping sometimes producing strings with different syntactic organizations; such syntactic changes are accompanied by immediate and dramatic changes in apparent stress and intonation although the physical signal itself never varies.     

The role of posture in sound localization

Studies of auditory localization revealed that where a subject hears a sound is dependent on both his perceived head position and the auditory cues at his ears. If an error is induced between his true and registered head posture, then errors in his auditory localizations of corresponding size and time course result. The presence of visual information prevents the development of postural errors and, consequently, prevents the development of errors in auditory localization, too. These observations are related to the oculogravic illusion and are interpreted as one aspect of the functioning of a spatial reference system involved in the maintenance of the constancies of auditory and visual detection.     

Anti-NMDA-Rezeptor-Enzephalitis

Die Anti-NMDA(N-Methyl-D-Aspartat)-Rezeptor-Enzephalitis ist eine seltene autoimmunologisch bedingte Erkrankung mit verschiedenen neuropsychiatrischen Symptomen, die durch den Nachweis von NMDA-Rezeptor-Antikörpern im Liquor diagnostiziert wird. Die gängigen Behandlungsprotokolle beinhalten ein Stufenschema der Immuntherapien; allerdings beruhen die therapeutischen Entscheidungen derzeit auf einem Grad-IV-Evidenzniveau. Wir berichten hier über zwei junge, unterschiedlich betroffene Patientinnen und beschreiben die Therapiestrategien inklusive der Kombination verschiedener Immuntherapien einschließlich Ocrelizumab und Überlegungen bezüglich Fertilitätserhalt.