Previous studies have proposed two cognitive mechanisms responsible for the Ebbinghaus illusion effect, i.e., contour interaction and size contrast. However, the neural underpinnings of these two mechanisms are largely unexplored. The present study introduced binocular depth to the Ebbinghaus illusion configuration and made the central target appear either in front of or behind the surrounding inducers in order to disturb size contrast instead of contour interaction. The results showed that the illusion effect, though persisted, was significantly reduced under the binocular depth conditions. Notably, the target with a larger perceived size reduced early alpha-band power (8-13 Hz, 0-100 ms after stimulus onset) at centroparietal sites irrespective of the relative depth of the target and the inducers, with the parietal alpha power negatively correlated with the illusion effect. Moreover, the target with a larger perceived size increased the occipito-parietal beta-band power (14-25 Hz, 200-300 ms after stimulus onset) under the no-depth condition, and the beta power was positively correlated with the illusion effect when the depth conditions were subtracted from the no-depth condition. The findings provided neurophysiological evidence in favor of the two cognitive mechanisms of the Ebbinghaus illusion by revealing that early alpha power is associated with low-level contour interaction and late beta power is linked to high-level size contrast, supporting the claim that neural oscillations at distinct frequency bands dynamically support different aspects of visual processing.
Humans ; Alpha Rhythm/physiology* ; Female ; Male ; Size Perception/physiology* ; Young Adult ; Adult ; Beta Rhythm/physiology* ; Photic Stimulation/methods* ; Illusions/physiology* ; Optical Illusions/physiology* ; Depth Perception/physiology*

Wernekink commissure syndrome is a rare midbrain syndrome with bilateral cerebellar dysfunction,eye movement disorder,and palatal myoclonus.Few cases of this syndrome have been reported in China,let alone those combined with hallucinations and involuntary groping.This paper reports the diagnosis and treatment of a case of Wernekink commissure syndrome with hallucinations and involuntary groping,aiming to enrich the knowledge about this disease for clinicians.
Humans ; Mesencephalon ; Ocular Motility Disorders/diagnosis* ; Spinal Cord ; Syndrome ; Hallucinations

Humans ; Cerebral Cortex ; Hallucinations/pathology* ; Neurodegenerative Diseases/pathology* ; Atrophy/pathology* ; Magnetic Resonance Imaging

OBJECTIVE: To evaluate the effectiveness of family-engaged multidimensional team planning and management for patients with severe stroke and low functional status and to identify factors predictive of improved outcome at 1 month after admission. METHODS: We retrospectively evaluated 50 patients who underwent family-engaged multidimensional rehabilitation for recovery from severe stroke due to primary unilateral cerebral lesions. The rehabilitation consisted of three phases: comprehensive multidimensional assessment, intensive rehabilitation, and evaluation. Functional Independence Measure (FIM) scores were calculated and used to predict the patients’ status at discharge. RESULTS: Although all FIM scores significantly improved after 1 month of rehabilitation, the motor FIM (mFIM) score improved the most (from 20.5±1.0 to 32.6±2.0). The total FIM (tFIM) and mFIM scores continued to improve from the first month to discharge (mean mFIM efficiency, 0.33). The high-efficiency patient group (mFIM efficiency ≥0.19) had a significantly higher discharge-to-home rate (44% vs. 13%), lower frequency of hemispatial neglect, and more severe finger numbness than the low-efficiency patient group (mFIM efficiency <0.19). The regression analyses revealed that besides lower mFIM and cognitive FIM scores at admission, unilateral spatial neglect, systemic comorbidities, and age were predictive of worse 1-month outcomes and tFIM scores (conformity, R²=0.78; predictive power, Akaike information criterion value=202). CONCLUSION: Family-engaged multidimensional team planning and management are useful for patients with severe stroke and low functional status. Furthermore, FIM scores at admission, age, unilateral spatial neglect, and systemic comorbidities should be considered by rehabilitation teams when advising caregivers on the probability of favorable outcomes after rehabilitation.
Caregivers ; Cerebrovascular Disorders ; Comorbidity ; Fingers ; Humans ; Hypesthesia ; Perceptual Disorders ; Rehabilitation ; Retrospective Studies ; Stroke ; Symptom Assessment

Naltrexone is a competitive antagonist of μ, δ, and κ opioid receptors. Naltrexone has been investigated for use an as anti-obesity agent in both the general population and in patients with severe mental illness, including schizophrenia. In patients with schizophrenia, however, potential psychotic symptoms due to adverse effects of naltrexone have not been investigated. Our case study, a relevant case report, and some related articles suggest that naltrexone might be associated with the emergence of visual hallucinations, which clinicians should be aware of.
Drug-Related Side Effects and Adverse Reactions ; Hallucinations ; Humans ; Naltrexone ; Narcotic Antagonists ; Receptors, Opioid ; Schizophrenia

Musical hallucinations remain a poorly understood clinical phenomenon, possibly because these types of hallucination have multiple causes and are rarely the focus of published reports. Here, the case of a 51-year-old female patient with a hearing impairment who developed musical hallucinations during treatment with ceftazidime, a third-generation cephalosporin, is presented. She responded to the discontinuation of ceftazidime and the initiation of low-dose olanzapine treatment. Musical hallucinations associated with ceftazidime are very rare, and the mechanisms underlying its occurrence remain unknown. Further studies will be necessary to determine the pathophysiology of adverse psychiatric reactions associated with ceftazidime.
Ceftazidime ; Drug-Related Side Effects and Adverse Reactions ; Female ; Hallucinations ; Hearing Loss ; Hearing ; Humans ; Middle Aged ; Music

Corollary discharge mechanism refers to the suppression of sensory consequences of self-generated actions; a process that serves to distinguish between self and non-self based on discrimination of origination of action. It explains, say for example, why we cannot tickle ourselves. This review discusses how corollary discharge model is an essential neural integration mechanism central to the motor functioning of animal kingdom. In this article, research conducted in the field of corollary discharge has been reviewed to understand the neuroanatomical and neurophysiological basis of corollary discharge and gain insight into the biochemical basis of its dysfunction. This review article also explores the role of corollary discharge and its dysfunction in the presentation of symptoms of schizophrenia, discussing the findings from corollary discharge studies on schizophrenia population. Lastly, the link between schizophrenia psychopathology and corollary discharge dysfunction has been highlighted, and an attempt has been made to establish a case for correction of corollary discharge deficit in schizophrenia through neuromodulation.
Animals ; Discrimination (Psychology) ; Hallucinations ; Motor Activity ; Psychopathology ; Schizophrenia ; Transcranial Direct Current Stimulation

No abstract available.
Codon ; Hallucinations ; Illusions

BACKGROUND AND OBJECTIVES: Mild cognitive impairment (MCI) is a disorder that usually occurs in the elderly, leading to dementia in some progressive cases. The purpose of this study is to examine the utility of central auditory processing tests as early diagnostic tools for identifying the elderly with MCI. SUBJECTS AND METHODS: This study was conducted on 20 elderly patients with MCI and 20 healthy matched peers. The speech perception ability in a quiet environment and in the presence of background noise and also temporal resolution were assessed by using Speech Perception in Noise (SPIN) and Gap in Noise (GIN) tests, respectively. RESULTS: The results indicated that the ability to understand speech in a quiet environment did not differ significantly between the two groups. However, SPIN at the three signal-tonoise ratios and the temporal resolution scores were significantly different between the two groups (p<0.001). CONCLUSIONS: Individuals with MCI appear to have poorer speech comprehension in noise and a lower temporal resolution than those of the same age, but without cognitive defects. Considering the utility of these tests in identifying cognitive problems, we propose that since the GIN test seems to be less influenced by intervening factors, this test can therefore, be a useful tool for the early screening of elderly people with cognitive problems.
Aged ; Auditory Perceptual Disorders ; Cognition ; Cognition Disorders ; Comprehension ; Dementia ; Humans ; Mass Screening ; Mild Cognitive Impairment ; Noise ; Speech Perception

OBJECTIVES: Several studies have delineated the relationship between hearing disturbances and the prevalence or characteristics of psychotic symptoms; however, most of those studies focused on psychiatric patients and not general inpatients. Delirium has a high incidence among general inpatients, and patients with delirium are easily affected by psychotic symptoms that lead to irritable behaviors. This study examined the relationship between hearing disturbance and psychotic symptoms among patients with delirium. METHODS: At the Asan Medical Center in Seoul, South Korea, this study examined 27 inpatients who had both delirium and hearing disturbances between January 1, 2009 and December 31, 2018, and 146 inpatients at the Asan Medical Center who had delirium but no hearing disturbances between July 1, 2018 and December 31, 2018. This study investigated whether the two groups showed differences in the prevalence and characteristics of delirium symptoms, particularly psychotic symptoms. In addition, the correlation between clinical characteristics of delirium and the recommended dosage of antipsychotics was analyzed in patients who had been diagnosed with delirium and had hearing disturbances. RESULTS: Compared to inpatients who only had delirium, those who had both delirium and hearing disturbances had a significantly higher prevalence of hallucination and delusion. CONCLUSION: The prevalence of psychotic symptoms, such as hallucination and delusion, was higher in patients who had both delirium and hearing disturbances, which is in line with the results from previous studies on psychiatric patients. Physicians should focus on improving communication with such patients by employing non-verbal communication methods.
Antipsychotic Agents ; Chungcheongnam-do ; Delirium ; Delusions ; Hallucinations ; Hearing ; Humans ; Incidence ; Inpatients ; Korea ; Prevalence ; Seoul