Neurological assessment of learning disorders

INTRODUCTION: The neurological concept of learning is approached from a cybernetic point of view, taking into account that a child should recognize a fact, learn it semantically and decided whether it is worth storing; the dynamic aspect of memory is the true motor of the ability to learn and all this is modulated by the attention factor. DEVELOPMENT: The neurological evaluation of learning disorders is based on clinical examination which includes the so-called minor signs of the noetic functions, specifically language, the praxes, gnosias, perceptive-motor function, laterality and the lexical, graphic and calculation functions together with the modulating element, mentioned above, of the level of attention with or without hyperactivity. These semiological elements are grouped into three major categories of syndromes: motor syndrome, dyslexic-dysgraphic-dyscalculation syndrome and the hyperkinetic syndrome or attention deficit with hyperactivity. We also note the differential diagnosis. We review the neurophysiological biological markers (EEG and brain mapping, cerebral evoked potentials, neurometry) and those based on neuroimaging techniques (cerebral CT, MR, SPECT and PET). CONCLUSIONS: The contribution of neurological assessment is considered as part of the functions of a multi-disciplinary team which should deal with the diagnosis and treatment of children with learning disorders.     

Neuropsychiatric performance of HIV-infected patients

AIM: Can neuropsychic impairment which is clinically observed in the case of HIV-infected patients be objectivized, and what is the relationship to somatic features caused by the disease? PATIENTS AND METHOD: 65 HIV-infected men with no history of drug-addiction were examined by means of a test battery which monitored the functions memory/concentration and speed of response. The probands were then compared to a healthy control group which was parallelized with respect to age, sex and education. Immune status, HIV and AIDS associated symptoms as well as educational diseases were checked for their connection with neuropsychic impairment. RESULTS: Compared to healthy persons HIV patients presented significant deficits with respect to memory and concentration but showed no reduction of speed of response. Significant correlation could be determined with only one somatic feature: Half of the patients who had lost more than 10% of their body weight during the preceding three months suffered from clinically relevant memory and concentration disorders. CONCLUSIONS: 1. The massive memory and concentration disorders impair and isolate the patients and can have considerable job-related consequences. 2. Measures preventing loss of weight should be initiated as early as possible. 3. Training sessions, e.g. nutritional consultation, must take the patients' deficits with respect to concentration and memory into consideration. 4. Possible connections between loss of weight and changes in brain metabolism should be examined. 5. Future studies should determine whether measures weight increase coincide with an improvement of memory and concentration.     

Amnesia and neglect: beyond the Delay-Brion system and the Hebb synapse

Hippocampal damage in people causes impairments of episodic memory, but in rats it causes impairments of spatial learning. Experiments in macaque monkeys show that these two kinds of impairment are functionally similar to each other. After any lesion that interrupts the Delay-Brion system (hippocampus, fornix, mamillary bodies and anterior thalamus) monkeys are impaired in scene-specific memory, where an event takes place against a background that is specific to that event. Scene-specific memory in the monkey corresponds to human episodic memory, which is the memory of a unique event set in a particular scene, as opposed to scene-independent human knowledge, which is abstracted from many different scenes. However, interruption of the Delay-Brion system is not sufficient to explain all of the memory impairments that are seen in amnesic patients. To explain amnesia the specialized function of the hippocampus in scene memory needs to be considered alongside the other, qualitatively different functional specializations of other memory systems of the temporal lobe, including the perirhinal cortex and the amygdala. In all these specialized areas, however, including the hippocampus, there is no fundamental distinction between memory systems and perceptual systems. In explaining memory disorders in amnesia it is also important to consider them alongside the memory disorders of neglect patients. Neglect patients fail to represent in memory the side of the world that is contralateral to the current fixation point, in both short- and long-term memory retrieval. Neglect was produced experimentally by unilateral visual disconnection in the monkey, confirming the idea that visual memory retrieval is retinotopically organized; patients with unilateral medial temporal-lobe removals showed lateralized memory impairments for half-scenes in the visual hemifield contralateral to the removal. Thus, in scene-memory retrieval the Delay-Brion system contributes to the retrieval of visual memories into the retinotopically organized visual cortex. This scene memory interpretation of hippocampal function needs to be contrasted with the cognitive-map hypothesis. The cognitive-map model of hippocampal function shares some common assumptions with the Hebb-synapse model of association formation, and the Hebb-synapse model can be rejected on the basis of recent evidence that monkeys can form direct associations in memory between temporally discontiguous events. Our general conclusion is that the primate brain encompasses widespread and powerful memory mechanisms which will continue to be poorly understood if theory and experimentation continue to concentrate too much, as they have in the past, on the hippocampus and the Hebb synapse.     

Selective increases of extracellular brain concentrations of aromatic and branched-chain amino acids in relation to deterioration of neurological status in acute (ischemic) liver failure

Four brain-injured subjects with semantic memory impairments are described. Two had sustained traumatic head injury and two had herpes simplex virus encephalitis. The study seeks to determine (a) whether subjects with non-progressive brain injury and impaired semantic memory perform similarly to patients with progressive disorders on a semantic memory battery and (b) whether the anatomical lesions of the present group of subjects are similar to those seen in patients with progressive disorders. Results suggests that scores on the semantic memory battery are broadly similar for patients with progressive and non-progressive disorders information from magnetic resonance imaging scans supports other findings that the crucial area involved in semantic memory lies in the left temporal neocortex.     

Shoulder disorders in general practice: incidence, patient characteristics, and management

OBJECTIVES: To study the incidence and management of intrinsic shoulder disorders in Dutch general practice, and to evaluate which patient characteristics are associated with specific diagnostic categories. METHODS: In 11 general practices (35,150 registered patients) all consultations concerning shoulder complaints were registered during a period of one year. Patients with an intrinsic shoulder disorder who had not consulted their general practitioner for the complaint during the preceding year (incident cases) were asked to participate in an observational study. Participants completed a questionnaire regarding the nature and severity of their complaints. The general practitioners recorded data on diagnosis and therapy. RESULTS: The cumulative incidence of shoulder complaints in general practice was estimated to be 11.2/1000 patients/year (95% confidence limits 10.1 to 12.3). Rotator cuff tendinitis was the most frequently recorded disorder (29%). There were 349 incident cases enrolled in the observational study. Patient characteristics showed small variations between different diagnostic categories. Age, duration of symptoms, precipitating cause and restriction of movement seemed to be discriminating factors. Twenty two percent of all participants received injections during the first consultation; most (85%) were diagnosed as having bursitis. The majority of patients with tendinitis (53%) were referred for physiotherapy. CONCLUSION: With respect to diagnosis and treatment, the practitioners generally appeared to follow the guidelines issued by the Dutch College of General Practitioners. Although the patient characteristics of specific disorders showed some similarities with the clinical pictures described in the literature, further research is required to demonstrate whether the proposed syndromes indeed constitute separate disorders with a different underlying pathology, requiring different treatment strategies.     

The child with lip, maxillary, palatal cleft

Clefting of lip, alveolus and palate may occur in multiple variations. It causes aesthetic and functional detractions. Soft palate clefts may result in hearing-, speech- and swallowing-disorders. Therefore the otolaryngologist is a very important member in the interdisciplinary team directory. A cleft-palate child belongs to an interdisciplinary consulting hour in special hospitals, where different medical specialties are involved. Most important for a sufficient medical rehabilitation are maxillofacial surgery, otolaryngology, paediatrics, plastic surgery, speech therapy, psychology and human genetics. Also many other specialties may be involved. The cleft demands a complete follow up from the child's birth until it is grown up. Hearing disorders are caused by eustachian tube disfunction. There is a high prevalence of hearing loss and middle ear diseases in cleft palate patients. Hearing losses due to middle ear effusions in the very young child. Without therapy up to 50% of the cleft palate population will develop chronic middle ear diseases with and without cholesteatomas. Early and consequent therapy with myringotomy and insertion of a tympanostomy ventilation tube is necessary and helps to avoid chronic hearing problems. There is no general accepted system of speech disorders in cleft palate patients because of the difference in shaping of the cleft and rehabilitation development. Essential for speech rehabilitation are an intact velopharyngeal system and a keen sense of hearing. Both of it is disturbed in cleft palate children. Speech disorders are treated by speech therapists with prior consultation of the interdisciplinary team. The author presents a system of primary, secondary and tertiary speech disorders in cleft palate children. Primary speech disorders are caused by faulty velopharyngeal valving, offering in hypernasality, weak plosives, fricatives and affricates. Secondary speech disorders are substitute mechanisms for plosives, nasal and pharyngeal sounds. Tertiary speech disorders are hyper- and hypofunctional dysphonias following primary and secondary speech dysfunctions.     

REM sleep deprivation potentiates the effects of imipramine and desipramine but not that of clomipramine in the forced swimming test

The human amnestic syndrome associated with lesions of the hippocampus and amygdala is characterized by a selective impairment of recent (explicit, episodic) memory. Benzodiazepine (BZ) treated normal subjects demonstrate similar, marked impairments in episodic memory, but in addition, BZ also induces sedation and inattention. Thus, the amnestic effects of BZ may be secondary to drug-induced sedation. However, when subjects were pretreated with the specific BZ receptor antagonist, flumazenil, the sedative and attentional effects of diazepam were blocked, but a marked impairment in episodic memory still occurred. This demonstrates that, using neuropharmacological methods, it is possible to produce a dissociation of memory impairment from inattention and sedation. Such distinct patterns of cognitive dysfunction may serve as models for clinical cognitive syndromes.     

Beta(3)-adrenoceptors mediate smooth muscle relaxation in the rat lower oesophageal sphincter

BACKGROUND: The neurological literature concerning disinhibition syndromes and secondary mania has run in parallel to clinical reports of bipolar disorder in old age. METHODS: A critical review was conducted of both the neurological and geriatric psychiatry literature in an attempt to integrate the two streams. RESULTS: Disinhibition syndromes include lateralization to the right hemisphere and localization of lesions to the orbito-frontal and basotemporal cortex involving limbic and frontal connections (orbito-frontal circuit). Mania in old age is associated with late onset, heterogeneous neurological disorders and poor outcome. CONCLUSION: Bipolar disorders in old age may be understood in the context of affective vulnerability influenced by a specific neurobiologic substrate. LIMITATIONS: The clinical literature consists predominantly of small case series and anecdotal reports. CLINICAL RELEVANCE: Improved understanding of these syndromes may elucidate the pathogenesis and etiology of bipolar disorders and the neuropsychiatric syndromes affecting mood, motivation and behavioural disinhibition.     

How many memory systems are there?

Proposes a ternary classificatory scheme of memory in which procedural, semantic, and episodic memory constitute a monohierarchical arrangement. In this scheme, episodic memory is a specialized subsystem of semantic memory, which in turn is a specialized subsystem of procedural memory. The 3 memory systems differ from one another in a number of ways, including the kind of consciousness that characterizes their operations. The ternary scheme overlaps with dichotomies and trichotomies of memory proposed by others. Evidence for multiple systems is reviewed, and illustrative data are provided from experiments. Direct priming effects were found to be both functionally and stochastically independent of recognition memory. (100 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Assessing capacity in the complex patient: RCAT's unique evaluation and consultation model.

This paper describes the development of a unique multidisciplinary patient capacity assessment team, the Regional Capacity Assessment Team (RCAT), which operates in the Calgary Health Region of Alberta. The goals of this paper are to provide a brief review of seminal models that influenced RCAT's development, discuss its ethical and theoretical underpinnings, and provide an overview of the RCAT approach to the completion of complex capacity assessments. The overview of the RCAT model will elucidate our multidisciplinary assessment algorithm, our consultation model, and describe our specialized assessment tools. This paper will be of interest to health care practitioners and administrators looking for a cost-effective, efficient, and clinically sound model for complex capacity assessments. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Axis I comorbidity of borderline personality disorder

OBJECTIVE: The purpose of this study was to assess the lifetime rates of occurrence of a full range of DSM-III-R axis I disorders in a group of patients with criteria-defined borderline personality disorder and comparison subjects with other personality disorders. METHOD: The axis I comorbidity of 504 inpatients with personality disorders was assessed by interviewers who were blind to clinical diagnosis and who used a semistructured research interview of demonstrated reliability. RESULTS: Four new findings emerged from this study. First, anxiety disorders were found to be almost as common among borderline patients (N=379) as mood disorders but far more discriminating from axis II comparison subjects (N=125). Second, posttraumatic stress disorder (PTSD) was found to be a common but not universal comorbid disorder among borderline patients, a finding inconsistent with the view that borderline personality disorder is actually a form of chronic PTSD. Third, male and female borderline patients were found to differ in the type of disorder of impulse in which they "specialized." More specifically, substance use disorders were significantly more common among male borderline patients, while eating disorders were significantly more common among female borderline patients. Fourth, a lifetime pattern of complex comorbidity (i.e., met DSM-III-R criteria for both a disorder of affect and a disorder of impulse at some point before the patients' index admission) was found to have strong positive predictive power for the borderline diagnosis as well as a high degree of sensitivity and specificity. CONCLUSIONS: These results suggest that the lifetime pattern of axis I comorbidity characteristic of borderline patients and distinguishing for the disorder is a particularly good marker for borderline personality disorder.     

Distinctive disorders are less prevalent

To test the hypothesis that nosologies are biased towards recognizing highly distinctive syndromes and therefore conflate those that are less distinctive, eight subjects judged the distinctiveness of 33 DSM-IV disorders and 20 rheumatic disorders. As predicted, judged distinctiveness was negatively correlated with prevalence for both sets of disorders.     

Course of psychiatric and substance abuse syndromes co-occurring with bipolar disorder after a first psychiatric hospitalization

BACKGROUND: Patients with bipolar disorder frequently meet criteria for other psychiatric and substance abuse diagnoses. To clarify relationships among these disorders, the authors examined the course of syndromes co-occurring with bipolar disorder for 12 months after a first hospitalization. METHOD: Seventy-seven patients were recruited from consecutive inpatient admissions who met DSM-III-R criteria for bipolar disorder, manic or mixed with psychosis. The 12-month syndromal course of co-occurring DSM-III-R alcohol and drug abuse disorders, posttraumatic stress disorder (PTSD), obsessive-compulsive disorder (OCD), and other anxiety disorders were longitudinally recorded. RESULTS: The rates of all syndromes, except other anxiety disorders, were elevated. OCD demonstrated an interval course that frequently mirrored the course of the bipolar disorder. The courses of PTSD and substance abuse syndromes were separate from that of the bipolar disorder in many of those with both syndromes. Alcohol and drug abuse syndromes were strongly correlated. CONCLUSION: The obsessive-compulsive syndrome may represent an alternative expression of bipolar disorder in some patients. In contrast, PTSD appears to represent a truly separate disorder, which is possibly more prevalent in bipolar patients due to a shared risk factor. Substance abuse does not appear to simply result from attempts at self-medication or from the impulsivity of mania. These results suggest that future studies examining the course of syndromes co-occurring with bipolar disorder are warranted.     

Psychometrically matched tasks evaluating differential fMRI activation during form and motion processing.

Objective: Deficits in visual perception and working memory are commonly observed in neuropsychiatric disorders and have been investigated using functional MRI (fMRI). However, interpretation of differences in brain activation may be confounded with differences in task performance between groups. Differences in task difficulty across conditions may also pose interpretative issues in studies of visual processing in healthy subjects. Method: To address these concerns, the present study characterized brain activation in tasks that were psychometrically matched for difficulty; fMRI was used to assess brain activation in 10 healthy subjects during discrimination and working memory judgments for static and moving stimuli. For all task conditions, performance accuracy was matched at 70.7%. Results: Areas associated with V2 and V5 in the dorsal stream were activated during motion processing tasks and V4 in the ventral stream were activated during form processing tasks. Frontoparietal areas associated with working memory were also statistically significant during the working memory tasks. Conclusions: Application of psychophysical methods to equate task demands provides a practical method to equate performance levels across conditions in fMRI studies and to compare healthy and cognitively impaired groups at comparable levels of effort. These psychometrically matched tasks can be applied to patients with a variety of cognitive disorders to investigate dysfunction of multiple a priori defined brain regions. Measuring the changes in typical activation patterns in patients with these diseases can be useful for monitoring disease progression, evaluating new drug treatments, and possibly for developing methods for early diagnosis. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

The functional status of arrhythmia patients in the late period after the radical correction of tetralogy of Fallot

OBJECTIVE: To assess the cognitive performance of elderly patients referred to the memory clinic. DESIGN: The patients were interviewed using the computerised mental state programme, GMS-AGECAT, and assessed on the Cognitive Assessment Scale (CAS) which includes the Elderly Cognitive Assessment Questionnaire (ECAQ) and the Cambridge Memory Test (CMT), modified for Chinese elderly. SUBJECTS: There were 72 Chinese elderly subjects aged 65 years and above, referred to the NUH Memory Clinic in the first year. RESULTS: Only 45 (62.5%) of the 72 subjects were diagnosed to have dementia using DSM III R criteria. There were 25 cases of Alzheimer's Disease and 20 multi-infarct dementia. In the non-demented group, 15 (20.8%) had depression or anxiety disorders and 12 (16.7%), had no mental disorders but had physical illness which could affect memory. There was a highly significant difference in the ECAQ, CMT and CAS scores of demented and non-demented elderly. There was also a significant difference in the cognitive performance of elderly with mild dementia and those with no mental disorder. CONCLUSION: The memory clinic is a useful facility for the diagnosis and management of dementia. The Cognitive Assessment Scale provides a valid and reliable battery of tests for dementia.     

Reduced benzodiazepine sensitivity in patients with panic disorder: comparison with patients with obsessive-compulsive disorder and normal subjects

OBJECTIVE: The authors sought to replicate their previous finding of reduced response to diazepam in patients with panic disorder, to test whether this effect was specific for panic disorder, and to determine whether this reduced response was merely an artifact of resistance to sedation from anxiety-related overarousal. METHOD: The effects of four increasing intravenous doses of diazepam on saccadic eye movement velocity and accuracy (the latter being a saccadic variable that is unaffected by sedation), short-term memory, and self- and observer-rated sedation were assessed in 18 patients with panic disorder, 15 patients with obsessive-compulsive disorder, and 14 normal comparison subjects. The ratios of effect to blood level areas under the curve for both ascending and descending limbs of the effect/blood level curves were compared for each variable. RESULTS: Patients with panic disorder showed significantly less diazepam effect on saccadic velocity and accuracy for the ascending limb of the blood level curve than comparison subjects. Patients with obsessive-compulsive disorder showed similar differences from comparison subjects but only for saccadic velocity. There were no group differences in diazepam effects on memory and sedation. CONCLUSIONS: Patients with panic disorder are less sensitive than comparison subjects to diazepam. Although this difference is not an artifact of resistance to sedation, it may not be specific for panic disorder but rather may reflect a more nonspecific aspect of anxiety disorders.     

Access and organization of goal-derived categories after traumatic brain injury

This study examined the access and organization of goal-derived categories in semantic memory with a group of chronic traumatic brain injured TBI adults and a group of age and gender-matched neurologically-intact controls. Goal-derived categories are developed by individuals for use in specialized contexts to achieve a goal, such as 'things to take on a camping trip.' Categories were presented to subjects in two task contexts: category verification and exemplar generation. Overall, the TBI subjects were able to accurately identify and organize category exemplars within particular categories. Interestingly, the TBI subjects produced significantly more total responses than the neurologically-intact subjects on exemplar generation; however, a high percentage of their responses (one-third) were inaccurate, consisting of out-of-set responses and repetitions. These findings suggest that difficulties in retrieval may exist in the presence of relatively intact access and organization of goal-derived category structure. The results are discussed relative to deficits in the executive control of verifying goal-directed behaviour and incomplete category representation.     

Patellofemoral disorders: a classification system and clinical guidelines for nonoperative rehabilitation

Patellofemoral disorders are among the most common clinical conditions managed in the orthopaedic and sports medicine setting. Nonoperative intervention is typically the initial form of treatment for patellofemoral disorders; however, there is no consensus on the most effective method of treatment. Although numerous treatment options exist for patellofemoral patients, the indications and contraindications of each approach have not been well established. Additionally, there is no generally accepted classification scheme for patellofemoral disorders. In this paper, we will discuss a classification system to be used as the foundation for developing treatment strategies and interventions in the nonsurgical management of patients with patellofemoral pain and/or dysfunction. The classification system divides the patellofemoral disorders into eight groups, including: 1) patellar compression syndromes, 2) patellar instability, 3) biomechanical dysfunction, 4) direct patellar trauma, 5) soft tissue lesions, 6) overuse syndromes, 7) osteochondritis diseases, and 8) neurologic disorders. Treatment suggestions for each of the eight patellofemoral dysfunction categories will be briefly discussed.     

The impact of logistical resources on prereferral team acceptability.

This study investigated the impact of logistical resources on the acceptability of student assistance team consultation to school staff. Elementary and middle school staff (N = 113) completed a measure of the acceptability of prereferral intervention team procedures while also rating the importance of five logistical supports for effective team functioning. A multiple regression analysis showed that the team process was more acceptable to staff who perceived these teams to be effective for helping students and to those who identified three supports for effective teaming: sufficient staff training in team procedures, adequate numbers of staff, and ample time. Results are discussed in the context of prior investigations, directions for future research, and implications for school practice. (PsycINFO Database Record (c) 2010 APA, all rights reserved)