Comparison of patient-controlled analgesia and sedation (PCAS) with remifentanil and propofol versus total intravenous anesthesia (TIVA) with midazolam, fentanyl, and propofol for colonoscopy

BACKGROUND

Colonoscopy is a commonly performed gastroenterological procedure in patients associated with anxiety and pain. Various approaches have been used to provide sedation and analgesia during colonoscopy, including patient-controlled analgesia and sedation (PCAS). This study aims to evaluate the feasibility and efficiency of PCAS administered with propofol and remifentanil for colonoscopy.

METHODS

This randomized controlled trial was performed in an authorized and approved endoscopy center. A total of 80 outpatients were recruited for the colonoscopy studies. Patients were randomly allocated into PCAS and total intravenous anesthesia (TIVA) groups. In the PCAS group, the dose of 0.1 ml/kg/min of the mixture was injected after an initial bolus of 3 ml mixture (1 ml containing 3 mg of propofol and 10 μg of remifentanil). Each 1 ml of bolus was delivered with a lockout time of 1 min. In the TIVA group, patients were administered fentanyl 1 μg/kg, midazolam 0.02 mg/kg, and propofol (dosage titrated). Cardiorespiratory parameters and auditory evoked response index were continuously monitored during the procedure. The recovery from anesthesia was assessed using the Aldrete scale and the Observer's Assessment of Alertness/Sedation Scale. The Visual Analogue Scale was used to assess the satisfaction of patients and endoscopists.

RESULTS

No statistical differences were observed in the Visual Analogue Scale scores of the patients (9.58 vs 9.50) and the endoscopist (9.43 vs 9.30). A significant decline in the mean arterial blood pressure, heart rate, and auditory evoked response index parameters was recorded in the TIVA group (P < 0.05). The recovery time was significantly shorter in the PCAS group than in the TIVA group (P = 0.00).

CONCLUSION

The combination of remifentanil and propofol could provide sufficient analgesia, better hemodynamic stability, lighter sedation, and faster recovery in the PCAS group of patients compared with the TIVA group.

The effect of offline anosognosia for hemispatial neglect on neglect rehabilitation in patients with subacute and chronic right hemispheric brain injury. A retrospective cohort study

CLINICAL TRIALS REGISTRATION NUMBER

NCT05145855.

Clinical application of repetitive transcranial magnetic stimulation in improving functional impairments post-stroke: review of the current evidence and potential challenges

In recent years, the stroke incidence has been increasing year by year, and the related sequelae after stroke, such as cognitive impairment, motor dysfunction, and post-stroke depression, seriously affect the patient's rehabilitation and daily activities. Repetitive transcranial magnetic stimulation (rTMS), as a safe, non-invasive, and effective new rehabilitation method, has been widely recognized in clinical practice. This article reviews the application and research progress of rTMS in treating different functional impairments (cognitive impairment, motor dysfunction, unilateral spatial neglect, depression) after stroke in recent years, and preliminary summarized the possible mechanisms. It has been found that the key parameters that determine the effectiveness of rTMS in improving post-stroke functional impairments include pulse number, stimulated brain areas, stimulation intensity and frequency, as well as duration. Generally, high-frequency stimulation is used to excite the ipsilateral cerebral cortex, while low-frequency stimulation is used to inhibit the contralateral cerebral cortex, thus achieving a balance of excitability between the two hemispheres. However, the specific mechanisms and the optimal stimulation mode for different functional impairments have not yet reached a consistent conclusion, and more research is needed to explore and clarify the best way to use rTMS. Furthermore, we will identify the issues and challenges in the current research, explore possible mechanisms to deepen understanding of rTMS, propose future research directions, and offer insightful insights for better clinical applications.

[Dystypia in a patient with subcortical ischemic stroke]

A 58-year-old, right-handed man noticed difficulty in typing and speech. On day 3 after onset, the day of admission, he had frontal lobe dysfunction including verbal fluency impairment and impairment of recent memory, although he did not have apraxia or visual agnosia. Moreover, he had difficulty typing in romaji, especially words containing contracted or double consonant sounds, although he was able to do this before onset by visually checking the keyboard. He had mild dysgraphia. MRI showed an infarct in the genu and posterior limb of the left internal capsule. SPECT revealed low-uptake lesions in the left frontal lobe. In the present case, we consider that the subcortical infarction disrupted the network between the thalamus and frontal lobe, resulting in dystypia due to difficulty with recalling romaji spelling.

Effects of prism adaptation and visual scanning training on perceptual and response bias in unilateral spatial neglect

In some patients with unilateral spatial neglect, symptoms reflect impaired lateralized spatial attention and representation (perceptual bias) whereas in others the inability to respond to stimuli located in contralesional space (response bias). Here, we investigated whether prismatic adaptation (PA) and visual scanning training (VST) differentially affect perceptual and response bias and whether rehabilitation outcome depends on the type of bias underlying symptoms. Two groups of neglect patients in the subacute phase were evaluated before, immediately after, and two weeks following 10 days of PA (n = 9) or VST (n = 9). Standard neuropsychological tests (i.e., Behavioural Inattentional Test, Diller cancellation test, and Line Bisection test) were administered to assess neglect symptoms, while the Landmark task was used to disentangle perceptual and response biases. Performance on the Landmark task revealed that PA was more effective in improving the perceptual bias, while VST mainly modulated the response bias. Neuropsychological tests performance suggested that VST is better suited to modulate neglect in patients with response bias, while PA may be effective in patients with both types of bias. These findings may offer novel insights into the efficacy of PA and VST in the rehabilitation of perceptual and response biases in patients with neglect.

Neural correlates of impaired cognitive processes underlying self-unawareness in Alzheimer's disease

Self-unawareness concerning current symptoms remains a clinical challenge in Alzheimer's disease. Reduced self-awareness likely depends on complex biopsychosocial mechanisms that comprise multiple cognitive processes, regulated by personal goals and values. We specifically reviewed the cognitive processes impaired in unaware participants with AD by emphasizing the related impaired brain activity observed during task-based fMRI. Unawareness can be explained by a failure in functioning of or in connection between brain regions that intervene in access, retrieval and updating of (present or extended) self-information (posterior midline, medial temporal, inferior parietal cortices), or in its monitoring, evaluation, or control (medial and lateral prefrontal cortices). Although one must be cautious when relating function to brain regions, impaired processes were tentatively related to the Cognitive Awareness Model. Although brain function depends on neural networks, impaired brain activity during cognitive processes was discussed according to previous studies reporting correlations between brain regions and scores of anosognosia. The review provides a framework to help clinicians considering processes that can explain unawareness in dementia. In patients at early stages of AD, different levels of awareness of cognitive or social clinical changes might be described as impairment in the interaction between specific cognitive processes and contents.

Sensory Integration Deficits in Neurodegenerative Diseases: Implications for Apraxia

OBJECTIVE

Apraxia is the inability to perform voluntary, skilled movements following brain lesions, in the absence of sensory integration deficits. Yet, patients with neurodegenerative diseases (ND) may have sensory integration deficits, so we tested the associations and dissociations between apraxia and sensory integration.

METHODS

A total of 44 patients with ND and 20 healthy controls underwent extensive testing of sensory integration (i.e., localization of tactile, visual, and proprioceptive stimuli; agraphesthesia; astereognosis) and apraxia (i.e., finger dexterity, imitation, tool use).

RESULTS

The results showed (i) that patients with Alzheimer's disease, corticobasal syndrome, or posterior cortical atrophy were impaired on both dimensions; (ii) An association between both dimensions; (iii) that when sensory integration was controlled for, the frequency of apraxia decreased dramatically in some clinical subgroups.

CONCLUSION

In a non-negligible portion of patients, the hypothesis of a disruption of sensory integration can be more parsimonious than the hypothesis of apraxia in case of impaired skilled gestures. Clinicians and researchers are advised to integrate sensory integration measures along with their evaluation of apraxia.

A review of the impairments, preserved visual functions, and neuropathology in 21 patients with visual form agnosia - A unique defect with line drawings

We present a comprehensive review of the rare syndrome visual form agnosia (VFA). We begin by documenting its history, including the origins of the term, and the first case study labelled as VFA. The defining characteristics of the syndrome, as others have previously defined it, are then described. The impairments, preserved aspects of visual perception, and areas of brain damage in 21 patients who meet these defining characteristics are described in detail, including which tests were used to verify the presence or absence of key symptoms. From this, we note important similarities along with notable areas of divergence between patients. Damage to the occipital lobe (20/21), an inability to recognise line drawings (19/21), preserved colour vision (14/21), and visual field defects (16/21) were areas of consistency across most cases. We found it useful to distinguish between shape and form as distinct constructs when examining perceptual abilities in VFA patients. Our observations suggest that these patients often exhibit difficulties in processing simplified versions of form. Deficits in processing orientation and size were uncommon. Motion perception and visual imagery were not widely tested for despite being typically cited as defining features of the syndrome - although in the sample described, motion perception was never found to be a deficit. Moreover, problems with vision (e.g., poor visual acuity and the presence of hemianopias/scotomas in the visual fields) are more common than we would have thought and may also contribute to perceptual impairments in patients with VFA. We conclude that VFA is a perceptual disorder where the visual system has a reduced ability to synthesise lines together for the purposes of making sense of what images represent holistically.

We should be screening for benign paroxysmal positional vertigo (BPPV) in all older adults at risk of falling: a commentary on the World Falls Guidelines

Benign paroxysmal positional vertigo (BPPV) is amongst the commonest causes of dizziness and falls in older adults. Diagnosing and treating BPPV can reduce falls, and thereby reduce fall-related morbidity and mortality. Recent World Falls Guidelines recommend formal assessment for BPPV in older adults at risk of falling, but only if they report vertigo. However, this recommendation ignores the data that (i) many older adults with BPPV experience dizziness as vague unsteadiness (rather than vertigo), and (ii) others may experience no symptoms of dizziness at all. BPPV without vertigo is due to an impaired vestibular perception of self-motion, termed 'vestibular agnosia'. Vestibular agnosia is found in ageing, neurodegeneration and traumatic brain injury, and results in dramatically increased missed BPPV diagnoses. Patients with BPPV without vertigo are typically the most vulnerable for negative outcomes associated with this disorder. We thus recommend simplifying the World Falls Guidelines: all older adults (>60 years) with objective or subjective balance problems, irrespective of symptomatic complaint, should have positional testing to examine for BPPV.

Discriminative value of different combinations of tests to detect unilateral neglect in patients with right hemisphere damage

BACKGROUND AND PURPOSE

This study was undertaken to assess the most sensitive combination of tests to detect peripersonal unilateral neglect (UN) after stroke.

METHODS

The present study is a secondary analysis of a previously reported multicentric study of 203 individuals with right hemisphere damage (RHD), mainly subacute stroke, 11 weeks postonset on average, and 307 healthy controls. A battery of seven tests, providing 19 age- and education-adjusted z-scores, were given: the bells test, line bisection, figure copying, clock drawing, overlapping figures test, and reading and writing. Statistical analyses used a logistic regression and a receiver operating characteristic (ROC) curve after adjustment on demographic variables.

RESULTS

A combination of four z-scores based on the following three tests provided good discrimination of patients with RHD from matched healthy controls: the starting point and the difference between the number of omissions on left and right sides from the bells test, rightward deviation in bisection of long lines (20 cm), and left-sided omissions in a reading task. The area under the ROC curve was 0.865 (95% confidence interval = 0.83-0.901), with sensitivity = 0.68, specificity = 0.95, accuracy = 0.85, positive predictive value = 0.90, and negative predictive value = 0.82.

CONCLUSIONS

The most sensitive and parsimonious combination of tests to detect UN after stroke relies on four scores from three simple tests (bells test, line bisection, and reading). Future study is warranted to assess its ability to account for the functional difficulties of UN in daily life in the patient's actual environment.

Network Localization of Awareness in Visual and Motor Anosognosia

OBJECTIVE

Unawareness of a deficit, anosognosia, can occur for visual or motor deficits and lends insight into awareness itself; however, lesions associated with anosognosia occur in many different brain locations.

METHODS

We analyzed 267 lesion locations associated with either vision loss (with and without awareness) or weakness (with and without awareness). The network of brain regions connected to each lesion location was computed using resting-state functional connectivity from 1,000 healthy subjects. Both domain specific and cross-modal associations with awareness were identified.

RESULTS

The domain-specific network for visual anosognosia demonstrated connectivity to visual association cortex and posterior cingulate while motor anosognosia was defined by insula, supplementary motor area, and anterior cingulate connectivity. A cross-modal anosognosia network was defined by connectivity to the hippocampus and precuneus (false discovery rate p < 0.05).

INTERPRETATION

Our results identify distinct network connections associated with visual and motor anosognosia and a shared, cross-modal network for awareness of deficits centered on memory-related brain structures. ANN NEUROL 2023;94:434-441.

The human brain networks mediating the vestibular sensation of self-motion

Vestibular Agnosia - where peripheral vestibular activation triggers the usual reflex nystagmus response but with attenuated or no self-motion perception - is found in brain disease with disrupted cortical network functioning, e.g. traumatic brain injury (TBI) or neurodegeneration (Parkinson's Disease). Patients with acute focal hemispheric lesions (e.g. stroke) do not manifest vestibular agnosia. Thus, brain network mapping techniques, e.g. resting state functional MRI (rsfMRI), are needed to interrogate functional brain networks mediating vestibular agnosia. Hence, we prospectively recruited 39 acute TBI patients with preserved peripheral vestibular function and obtained self-motion perceptual thresholds during passive yaw rotations in the dark and additionally acquired whole-brain rsfMRI in the acute phase. Following quality-control checks, 26 patient scans were analyzed. Using self-motion perceptual thresholds from a matched healthy control group, 11 acute TBI patients were classified as having vestibular agnosia versus 15 with normal self-motion perception thresholds. Using independent component analysis on the rsfMRI data, we found altered functional connectivity in bilateral lingual gyrus and temporo-occipital fusiform cortex in the vestibular agnosia patients. Moreover, regions of interest analyses showed both inter-hemispheric and intra-hemispheric network disruption in vestibular agnosia. In conclusion, our results show that vestibular agnosia is mediated by bilateral anterior and posterior network dysfunction and reveal the distributed brain mechanisms mediating vestibular self-motion perception.

The 'healthy side' of anosognosia for hemiplegia: Increased sense of agency for the unimpaired limb or motor compensation?

OBJECTIVES

Anosognosic patients show a lack of awareness for their hemiplegia coupled with a distorted sense of agency for the actions performed by the plegic limbs. Since anosognosia is often associated with right brain damage, this hemisphere seems to play a dominant role in monitoring awareness for motor actions. Therefore, we would expect that anosognosic patients show distorted awareness and sense of agency also for actions performed with the unimpaired limb.

METHOD

To test this hypothesis, we induced illusory actions that could be congruent or incongruent with a preceding verbal command. A group of 16 right brain-damaged patients performed this task and then rated i) their ability to anticipate the actions, ii) their sense of agency and iii) their sense of ownership for each limb. Measures of awareness, neglect and motor impairment were also considered for the patient group.

RESULTS

Following incongruent actions with the unimpaired limb, less aware patients showed a relatively mild distortion in all three aspects. In addition, we also found a crucial relationship between motor impairment (for the plegic limb) and sense of agency for both plegic and healthy limbs.

CONCLUSION

Although the distortion linked to both limbs supports the initial hypothesis that the right hemisphere is responsible for monitoring awareness for action for the whole body, our data also suggest that the observed distortion may be linked to a motor compensatory phenomenon, not necessarily related to awareness processes.

Visual objects and their colors

The ventral temporal cortex hosts key regions for the high-level visual processing of object shape and color. These areas represent nodes of large-scale neural circuits dedicated to object recognition. In the language-dominant hemisphere, some of these regions communicate with the language systems; by assigning verbal labels to percepts, these circuits speedup stimulus categorization, and permit fast and accurate interindividual communication. By impairing the functioning of these circuits, neurological damage may provoke disabling disorders of the processing of visual objects and of their colors. Brain damage of vascular, degenerative, toxic, or traumatic origin can induce deficits at different levels of visual processing, from the building of shape- or wavelength-invariant percepts, to their connections with semantic knowledge and with the appropriate lexical entry. After an overview of the neuroimaging of domain-preferring regions for object shape and color in the ventral temporal cortex, this chapter reviews evidence from historical and recent cases of acquired visual agnosia and color processing deficits. A recurrent motif emerging from patients' patterns of performance and lesion locations is the existence of caudo-rostral gradients in the ventral occipito-temporal cortex, spanning from more perceptual to more cognitive stages of processing.

Cortical disorders of speech processing: Pure word deafness and auditory agnosia

Selective disorders of auditory speech processing due to brain lesions are reviewed. Over 120 years after the first anatomic report (Dejerine and Sérieux, 1898), fewer than 80 cumulative cases of generalized auditory agnosia and pure word deafness with documented brain lesions are on record. Most patients (approximately 70%) had vascular lesions. Damage is very frequently bilateral in generalized auditory agnosia, and more frequently unilateral in pure word deafness. In unilateral cases, anatomical disconnection is not a prerequisite, and disorders may be due to functional disconnection. Regardless of whether lesions are unilateral or bilateral, speech processing difficulties emerge in the presence of damage to the superior temporal regions of the language-dominant hemisphere, suggesting that speech input is processed asymmetrically at early stages already. Extant evidence does not allow establishing whether processing asymmetry originates in the primary auditory cortex or in higher associative cortices, nor whether auditory processing in the brainstem is entirely symmetric. Results are consistent with the view that the difficulty in processing auditory input characterized by quick spectral and/or temporal changes is one of the critical dimensions of the disorder. Forthcoming studies should focus on detailed audiologic, neurolinguistic, and neuroanatomic descriptions of each case.

Independence in Daily Activities after Stroke among Occupational Therapy Patients and Its Relationship with Unilateral Neglect

More research is needed to better understand the impact of occupational therapy (OT) in stroke patients and syndromes of unilateral neglect (UN) and anosognosia. A prospective, observational, longitudinal design was conducted on a sample of 27 OT patients. The objectives were to examine: (1) the presence of UN and anosognosia; (2) the functional outcomes; and (3) the association of UN at baseline with functional status at discharge from OT. The outcomes were Barthel (functional independence) and the Rivermead Mobility Index (RMI). The baseline proportion of participants with UN was 33% according to the Star Cancellation Test (STC), and 48.1% according to the Catherine Bergego Scale (CBS) therapist-version. There was a significant difference between the therapist and participant-rated CBS scores (p = 0.004). Functional independence improved significantly between the initial and final assessments (p < 0.001); the effect size (r) was large (r = 0.61). There was a significant improvement in RMI scores (p < 0.001), which was large in size (r = 0.59). Both the STC and CBS-therapist scores were significantly correlated with the Barthel (p < 0.001, p = 0.005, respectively) and with the RMI (p = 0.004, p = 0.028, respectively). The participants substantially enhanced their functional status skills. UN and anosognosia were common problems, and neglect was associated with worse OT program outcomes.

Simultaneous auditory agnosia: Systematic description of a new type of auditory segregation deficit following a right hemisphere lesion

We investigated auditory processing in a young patient who experienced a single embolus causing an infarct in the right middle cerebral artery territory. This led to damage to auditory cortex including planum temporale that spared medial Heschl's gyrus, and included damage to the posterior insula and inferior parietal lobule. She reported chronic difficulties with segregating speech from noise and segregating elements of music. Clinical tests showed no evidence for abnormal cochlear function. Follow-up tests confirmed difficulties with auditory segregation in her left ear that spanned multiple domains, including words-in-noise and music streaming. Testing with a stochastic figure-ground task-a way of estimating generic acoustic foreground and background segregation-demonstrated that this was also abnormal. This is the first demonstration of an acquired deficit in the segregation of complex acoustic patterns due to cortical damage, which we argue is a causal explanation for the symptomatic deficits in the segregation of speech and music. These symptoms are analogous to the visual symptom of simultaneous agnosia. Consistent with functional imaging studies on normal listeners, the work implicates non-primary auditory cortex. Further, the work demonstrates a (partial) lateralisation of the necessary anatomical substrate for segregation that has not been previously highlighted.

Altered large-scale organization of shape processing in visual agnosia

Recent findings suggest that both dorsal and ventral visual pathways process shape information. Nevertheless, a lesion to the ventral pathway alone can result in visual agnosia, an impairment in shape perception. Here, we explored the neural basis of shape processing in a patient with visual agnosia following a circumscribed right hemisphere ventral lesion and evaluated longitudinal changes in the neural profile of shape representations. The results revealed a reduction of shape sensitivity slopes along the patient's right ventral pathway and a similar reduction in the contralesional left ventral pathway. Remarkably, posterior parts of the dorsal pathway bilaterally also evinced a reduction in shape sensitivity. These findings were similar over a two-year interval, revealing that a focal cortical lesion can lead to persistent large-scale alterations of the two visual pathways. These alterations are consistent with the view that a distributed network of regions contributes to shape perception.

Depersonalization and Allied Disturbances in Childhood

Depersonalization, derealization, unreality feelings, metamorphopsia and similar symptoms are not unusual in neuro-psychiatric patients. They are said to be extremely rare in children, Tramer (22) does not mention them, and Kanner (9) remarks only that “feelings of unreality are exceedingly rare in children. Things seem unreal to the patient, different from what he knows them to be. He is fully aware of the incongruity of his experience, which sometimes causes considerable distress.” He quotes the case of a slightly retarded boy of almost 14 years who combined feelings of unreality and derealization with occasional macropsia.

Normal and Abnormal Depersonalization

This paper is offered as a contribution to the better understanding of depersonalization. It is divided into two sections. In the first section an account is given of the occurrence of brief episodes of depersonalization in young normal adults. In the second section a consistent interpretation of the symptoms of the syndrome itself is attempted. The two sections are loosely connected; the conclusion drawn from the study of the material in the first section—that it is the persistence, and not the nature of depersonalization which is abnormal—needs to be applied to the considerations advanced in the second. The interpretation will do as well for the brief experiences as for the established syndrome. The writer hopes that—if the interpretation is acceptable—the way will be cleared for attention to the remaining problem posed by this perplexing condition; why, in some cases, it endures. The following abbreviations are used throughout: For the depersonalization syndrome DP; for the depersonalization symptom,dp; for derealization,dr; for desomatization,ds; for the loss of feeling which frequently accompanies the other symptoms,dE; for visualization,vs, and for loss of visualization,dv; for the slowing-up of subjective time,dT.

Self-Awareness for Memory Impairment in Amnestic Mild Cognitive Impairment: A Longitudinal Study

AIM

To assess memory impairment insight as a predictor of dementia and Alzheimer's disease (AD) in amnestic mild cognitive impairment (MCI).

METHODS

To verify whether the awareness of memory impairment assessed by Geriatric Depression Scale (GDS) was associated with the risk of progression to dementia and AD in a cohort of MCI, we used a Cox regression model adjusted for age, sex, education, subtypes of amnestic MCI, Mini-Mental State Examination, Cumulative Illness Rating Scale severity index, and apolipoprotein E genotype.

RESULTS

During a follow-up of 27.7 (20.8) months, 205 (63.3%) of 324 patients with amnestic MCI progressed to dementia, including 141 to AD. No association was found in the unadjusted, partially adjusted (for sociodemographic variables), and fully adjusted multivariate Cox analysis between the awareness of memory impairment and the progression to dementia and AD.

DISCUSSION

Awareness or anosognosia of memory deficits, identified by GDS, is not useful to predict progression to dementia of patients with amnestic MCI.

Challenges With Manual-Based Multimodal Psychotherapy for People With Alzheimer's Disease: A Case Study

Earlier detection of dementia requires increased knowledge of how to help people in the early stages of dementia. However, few studies have focused on how psychotherapy should be adapted to improve the outcome of therapy for people with Alzheimer's disease. The aims of the present study were to identify and to explore possible obstacles encountered during the use of manual-based psychotherapy for people with early-stage Alzheimer's disease. The study found that individual adaptations to the treatment manual were necessary, particularly the modification of memory aids in order to adapt them to patients' functional level and previous experience with modern technology. In addition, caregivers were essential for both treatment and homework completion, while reduced awareness constituted an obstacle for adherence to the manual.

[Study of attentional bias in neglect patients by grey discriminant test]

OBJECTIVE

To explore the attentional bias in unilateral spatial neglect (USN) patients.

METHODS

The grey discriminant test was conducted on 12 right-brain-damaged patients with USN (USN+), 12 right-brain-damaged patients with no evidence of USN (USN-) and 20 health controls (HC). They were matched for age, years of education, mini-mental state examination (MMSE) scores and handedness. And all patients were recruited from First Affiliated Hospital of Anhui Medical University. The attentional deviation scores were compared between three groups.

RESULTS

The differences in scores of neglect tests for the USN+, USN- and HC groups were significant (Albert test: USN+ group -0.56 ± 0.39, USN- group 0.00 ± 0.00, HC group 0.00 ± 0.00, F((2, 41)) = 33.708, P < 0.001; line bisection test: USN+ group 0.28 ± 0.29, USN- group 0.03 ± 0.04, HC group -0.02 ± 0.04, F((2, 41)) = 14.527, P < 0.001; clock drawing by memory: USN+ group 3.58 ± 4.03, USN- group 0.08 ± 0.29, HC group 0.00 ± 0.00, F((2, 41)) = 12.558, P < 0.001; daisy copying: USN+ group 0.83 ± 0.65, USN- group 0.13 ± 0.23, HC group 0.00 ± 0.00, F((2, 41)) = 21.621, P < 0.001). The comparative results of lesion locations showed that USN+ patients were predominantly related to lesions in temporal-parietal junction. The attentional deviation scores for the USN+, USN- and HC groups were 0.92 ± 0.11, 0.41 ± 0.12 and -0.28 ± 0.15 respectively. The difference was significant (F((2, 41)) = 334.324, P < 0.001). There was with a small leftward bias in the HC group and a rightward bias in the USN+ and USN- groups. LSD test revealed that the USN+ group displayed a rightward bias much strongly than the USN- group (P < 0.001). And the results of grey discriminant test were consistent with the neglect symptoms.

CONCLUSIONS

The USN patients show a marked attentional bias toward the right side of space. And it may be attributed to the dysfunction of temporal-parietal junction.

Nutrient removal in wastewater treatment high rate algal ponds with carbon dioxide addition

The influence of CO2 addition to high rate algal ponds (HRAPS) on nitrogen removal was investigated using two pilot-scale HRAPs operated with different hydraulic retention times (HRT: 4 and 8 days), and was compared to the nitrogen removal by the 8-day HRT pond before CO2 addition was installed. Nitrogen balances were calculated by partitioning total nitrogen into organic and inorganic nitrogen (NH4+-N and NO3--N), and by separation of the organic nitrogen into particulate (PON) and dissolved organic nitrogen (DON). PON was further divided into algal organic nitrogen (AON) and bacteria organic nitrogen (BON) to investigate nitrogen mass flow in the HRAPS. This research shows that the proportion of algae in the algal/bacterial biomass in the longer 8-day HRT HRAP8d (55.6%) was appreciably lower than that in the shorter 4-day HRT HRAP4d (80.5%) when CO2 was added to control the maximum pH to <8.0 during the summer. Higher bacterial biomass in the longer 8-day HRT HRAP corresponded with higher nitrification rates, indicating that the longer 8-day HRT in the summer was detrimental for two reasons: lower algal productivity and increased nitrogen loss through nitrification/denitrification. Overall nitrogen removal of approximately 60% in the HRAPS with CO2 addition was mainly achieved by algal assimilation followed by sedimentation in the settling unit.

[Self-awareness of deficits in Huntington's and Parkinson's disease]

Impaired self-awareness of deficits has been referred to in literature as anosognosia, unawareness, denial of deficits and impaired insight. In this article we briefly present the terminology used in studies of impaired self-awareness in neurological disorders and we review the literature on self-awareness of deficits in Huntington's disease (HD) and Parkinson's diseases (PD) in terms of daily function, motor impairment, cognitive function and social-emotional function in both HD and PD. HD patients may exhibit impaired self-awareness of deficits in all domains, regardless of the cognitive status, while impaired self-awareness of deficits in PD is linked to dementia. Both HD and PD patients may be unaware of involuntary movements. Only one of the reviewed studies aimed at comparing the self-awareness of deficits in PD and HD, which indicates that further research addressing this topic is needed. Next, theoretical explanations of unawareness of involuntary movements based on psychodynamic, cognitive and neurophysiological approaches are presented. Finally, the methodological shortcomings of the reviewed articles are discussed, alongside with the recommendations for future studies.

Tight link between our sense of limb ownership and self-awareness of actions

BACKGROUND AND PURPOSE

Hemiparetic stroke patients with disturbed awareness for their motor weakness (anosognosia for hemiparesis/-plegia [AHP]) may exhibit further abnormal attitudes toward or perceptions of the affected limb(s). The present study investigated the clinical relationship and the anatomy of such abnormal attitudes and AHP.

METHODS

In a new series of 79 consecutively admitted acute stroke patients with right brain damage and hemiparesis/-plegia, different types of abnormal attitudes toward the hemiparetic/plegic limb (asomatognosia, somatoparaphrenia, anosodiaphoria, misoplegia, personification, kinaesthetic hallucinations, supernumerary phantom limb) were investigated.

RESULTS

Ninty-two percent of the patients with AHP showed additional "disturbed sensation of limb ownership" (DSO) for the paretic/plegic limb. The patients had the feeling that their contralesional limb(s) do not belong to their body or even belong to another person. Analysis of lesion location revealed that the right posterior insula is a crucial structure involved in these phenomena.

CONCLUSIONS

DSO for hemiparetic/-plegic limbs and AHP are tightly linked both clinically and anatomically. The right posterior insula seems to be a crucial structure involved in the genesis of our sense of limb ownership and self-awareness of actions.

The effectiveness and ethical justification of psychiatric outpatient commitment

Studies link involuntary outpatient commitment with improved patient outcomes, fueling debate on its ethical justification. This study compares inpatient utilization for committed outpatients in the 1990s with those who were not under outpatient civil commitment orders. Findings reveal committed outpatients had higher utilization of inpatient services and restraint episodes prior to their commitment compared with a control group. Committed outpatients also were more likely to have been on discharge status at the time of admission, have been admitted involuntarily under emergency legal procedures, and have had a greater number of admissions and hospital days prior to their commitment. Following commitment, patients had fewer hospitalizations, shorter lengths of stay, fewer seclusion episodes and hours, and fewer restraint episodes and hours. Findings are discussed within the context of parens patriae and therapeutic jurisprudence, and support medical and public policy justifications for ethical uses of outpatient civil commitment laws for seriously mentally ill patients.

Abnormal magnocellular pathway visual processing in infants at risk for autism

BACKGROUND

A wealth of data has documented impairments in face processing in individuals with autism spectrum disorders (ASD). Recently, the suggestion has been made that these impairments may arise from abnormal development of a subcortical system involved in face processing that originates in the magnocellular pathway of the primate visual system.

METHODS

To test this developmental hypothesis, we obtained visual perceptual data from 6-month-old infants who were at risk for ASD because they had an older sibling diagnosed with the disorder ("high-risk infants"). To measure sensitivity of the magnocellular (M) pathway and, for comparison, of the parvocellular (P) visual pathway, we employed visual stimuli designed to selectively stimulate the two. Sensitivity data from high-risk infants (n = 13) were compared with data from matched control infants (i.e., "low-risk" infants with no family history of ASD, n = 26).

RESULTS

On the P pathway stimulus, high-risk infants exhibited sensitivities that were identical to those of control infants. By contrast, on the M pathway stimulus, high-risk infants exhibited sensitivities nearly twofold greater than those of control infants.

CONCLUSIONS

Given that ASD and its symptoms are known to run in families, these preliminary results suggest that ASD may be associated with abnormal M pathway function early in infancy, which may aid in early diagnosis of the disorder.

Gonadal steroids and visuo-spatial abilities in adult males: implications for generalized age-related cognitive decline

The relationship between the gonadal steroids, testosterone and estrogen, and individual and group differences in performance on some cognitive tasks remains unclear but sex differences favoring males on some tests of visuo-spatial ability are large and robust. This aim of this review is to assess evidence for both organizational and activational effects of gonadal steroids as the principle cause of sex difference in visuo-spatial ability. Additionally, the implications of this relationship are discussed in the context of decreasing levels of gonadal steroids in aging males and psychological theories of generalized age-related cognitive decline. Based upon human and non-human research gonadal steroids have organizational effects on visuo-spatial ability in adulthood. Activational effects of gonadal steroids on visuo-spatial ability appear most dominant in older men and are necessary for maintaining optimal visuo-spatial ability; randomized clinical trials show that testosterone supplementation improves performance. Additionally, decreasing gonadal steroid levels in aging males may contribute to generalized age-related cognitive decline. Future supplementation studies in men should attempt to control for constituent abilities related to visuo-spatial task performance, and investigate interactions between dosage levels and baseline gonadal status. Further future animal research is required to investigate changes in gonadal steroid levels and their relationship to neurotransmitter systems, neural plasticity, and behavioral correlates.

Incidence of late stent thrombosis with bare-metal, sirolimus, and paclitaxel stents

Stent thrombosis has become a major concern for interventional cardiology. Although infrequent, it is associated with significant morbidity and mortality. Recent attention has focused on the frequency of this complication with drug-eluting stents compared with bare-metal stents in regard to the timing (early, late, or very late) of the event, underlying mechanisms involved, and preventive strategies. Although dual antiplatelet therapy (aspirin plus thienopyridine) is crucial in mitigating the problem, there are significant issues with this management strategy, including the duration of dual antiplatelet treatment, patient compliance, variability in individual response to therapy, bleeding risk, and management of subsequent noncardiac surgical procedures. Newer strategies being evaluated to enhance the safety of drug-eluting stents include different alloys and stent designs, revisions in the polymer or drug utilized, and, ultimately, bioabsorbable platforms.

Random number generation as an index of controlled processing

Random number generation (RNG) is a functionally complex process that is highly controlled and therefore dependent on Baddeley's central executive. This study addresses this issue by investigating whether key predictions from this framework are compatible with empirical data. In Experiment 1, the effect of increasing task demands by increasing the rate of the paced generation was comprehensively examined. As expected, faster rates affected performance negatively because central resources were increasingly depleted. Next, the effects of participants' exposure were manipulated in Experiment 2 by providing increasing amounts of practice on the task. There was no improvement over 10 practice trials, suggesting that the high level of strategic control required by the task was constant and not amenable to any automatization gain with repeated exposure. Together, the results demonstrate that RNG performance is a highly controlled and demanding process sensitive to additional demands on central resources (Experiment 1) and is unaffected by repeated performance or practice (Experiment 2). These features render the easily administered RNG task an ideal and robust index of executive function that is highly suitable for repeated clinical use.

The association between endogenous free testosterone and cognitive performance: a population-based study in 35 to 90 year-old men and women

The relationship between testosterone (T) and cognition has yielded conflicting evidence, showing both positive and negative influences of T on cognitive performance. The association between free testosterone (FT) and cognition was revisited in a large population-based sample of 1276 women and 1107 men (35-90 years of age), assessed individually on visuospatial, verbal fluency, semantic, and episodic memory tasks. For men, higher FT levels were associated with better visuospatial abilities, semantic memory, and episodic memory, with greater positive influence with increasing age. Statistical covariates included age, education, and select medications. For women, FT was negatively associated with verbal fluency, semantic memory, and episodic memory, although only verbal fluency was significant at conventional alpha levels. These results support the claim that FT exerts sex-specific influences on cognitive performance.

Incidence and diagnosis of anosognosia for hemiparesis revisited

BACKGROUND

In previous studies, the incidence of anosognosia for hemiparesis has varied between 17% and 58% in samples of brain damaged patients with hemiparesis.

OBJECTIVE

To determine whether this wide variation might be explained by the different criteria used for diagnosing anosognosia.

METHODS

128 acute stroke patients with hemiparesis or hemiplegia were tested for anosognosia for hemiparesis using the anosognosia scale of Bisiach et al.

RESULTS

94% of the patients who were rated as having "mild anosognosia"-that is, they did not acknowledge their hemiparesis spontaneously following a general question about their complaints-suffered from, and mentioned, other neurological deficits such as dysarthria, ptosis, or headache. However, they immediately acknowledged their paresis when they were asked about the strength of their limbs. Their other deficits clearly had a greater impact. These patients had significantly milder paresis than those who denied their disorder even when asked directly about their limbs.

CONCLUSIONS

Patients who do not mention their paresis spontaneously but do so when questioned about it directly should not be diagnosed having "anosognosia." If this more conservative cut off criterion is applied to the data of the present as well as previous studies, a frequency of between 10% and 18% for anosognosia for hemiparesis is obtained in unselected samples of acute hemiparetic stroke patients. The incidence thus seems smaller than previously assumed.

[What do you actually see? Visual impairments and their simulation for well-seeing subjects]

Most physicians know little about how persons with limited vision perceive something. Sometimes, simple technical aids can make it possible to get an idea as to what a visual disorder means to the person involved. Examples of this are the wearing of glasses of varying positive power and light transmittance, or the study of case histories, paintings and photographic simulations. Among the latter are a woman who painted what she 'saw' with her removed eye, an anophthalmic man who painted from memory, and the painting of a protanopic artist who chose colours by reading the labels on the paint tubes. Thus one may gain insight in disturbances such as phantom images, diminished visual acuity and visual field loss, metamorphopsia, diplopia, dazzling, and visual agnosia. And also in disturbed image fusion, in depth and stereoscopic vision, dark adaptation and colour vision, as well as diminishing visual functions at high age. This article contains colour illustrations that simulate the disturbances.

Stroke hemiplegia and specular image: lessons from self-portraits

Hemiplegic patients suffer from difficulties in self-awareness, either due to specific neurological disturbances of body image or to psychological problems with their I images. Both types of difficulty have to do with the specular image as defined by Lacan (1966a) (i.e., the psychic structure that links the body with the symbolic and imaginary components of identity, and neutralizes the real objects involved in mother-child exchange). This study is devoted to analyzing how recent right and left brain vascular lesions affect specular image. Multivariate Analysis of 308 self-portraits of right and left brain injured stroke patients and control participants was performed. This revealed three dominant types of self-portrait: 1) Erect, complete, and clothed self-portraits were predominantly drawn by normal participants. 2) Erect self-portraits, lacking clothes, hands, and/or mouth and eyes were found in all groups of participants, predominantly in patients with speech disorders. Lack of hands and face features are indications of the challenge brought to the symbolic and imaginary aspects of identity by any sudden handicap, whether or not caused by a brain lesion, while symmetry of lacks and verticality show that body image may retain its structuring value even in brain lesions. 3) This is not the case in neurological disorders of body image, since inclined portraits with unilateral omissions were predominantly drawn by patients with right brain lesions. These unilateral omissions proved not only to result from cognitive deficiencies, but also to reflect the fragmentation of specular image, and in one case, the concomitant undue appearance of the object.

Dissociation between personal and extrapersonal neglect in a crossed aphasia study

Abstract Several reports document crossed aphasia following a right cerebral infarct. However, few of them provide a detailed investigation of associated neuropsychological disorders. A personal neglect disorder with no difficulty in orienting attention in the contralesional space has not been frequently reported independently of lesion side for the language deficit. In most cases, the deficit is described in the acute period. We report the case of a patient who showed severe crossed aphasia several months after cerebral damage. In addition to his language deficit, he suffered from finger agnosia, acalculia, and right/left confusion. Although he was able to orient attention in the contralesional space, he had a persistent personal neglect disorder with severe difficulty in attending to his own body. Results suggest that right hemisphere language dominance does not preclude ipsilateral specialisation for other functions. Furthermore, the dissociation between the two spatial functions provides further confirmation that they are subserved by two independent systems.