Sex differences in perception of temporal order

On duration judgments lasting seconds to minutes, which are thought to be cognitively mediated, women typically perceive time intervals as longer than men do. On a perceptual level in the milliseconds range, few reports indicate higher acuity of temporal processing in men than in women. In this study, sex differences in the perception of temporal order of two acoustic stimuli were identified in neurologically healthy subjects, as well as in brain-injured patients with lesions in either the left or the right hemisphere. Women needed longer interstimulus intervals than men before they were able to indicate the correct temporal order of two clicks. Neurobiological evidence and findings on cognitive strategies are discussed to explain the apparent psychophysical sex differences.

Seeing the action: neuropsychological evidence for action-based effects on object selection

Previous studies have shown that selection for perceptual report is often limited to one object at a time, with elements being selected together if they belong to part of the same perceptual group. Here we used the neuropsychological phenomenon of extinction in human patients with parietal lesions to show that selection is influenced also by action relations between objects. Performance was better for objects that were positioned spatially so that they could be used together, relative to objects that were positioned inappropriately for their combined use. The action relation was critical, as performance for pictures did not improve if the items were only verbally associated. We found the opposite result with words. Effects of action relations emerged even on trials where only one object could be reported, showing implicit coding of 'action' units for selection. The effects of verbal associations may instead reflect priming between lexical entries.

Comparison of eyeblink conditioning in patients with superior and posterior inferior cerebellar lesions

The aim of the present study was to compare eyeblink conditioning in cerebellar patients with lesions including the territory of the superior cerebellar artery (SCA) and in patients with lesions restricted to the territory of the posterior inferior cerebellar artery (PICA). The cerebellar areas known to be most critical in eyeblink conditioning based on animal data (i.e. Larsell lobule H VI and interposed nucleus) are commonly supplied by the SCA. Eyeblink conditioning was expected to be impaired in SCA, but not in PICA patients. A total of 27 cerebellar patients and 25 age-matched controls were tested. Cerebellar lesions were primarily unilateral (n = 20). Most patients suffered from ischaemic infarctions of the SCA (n = 11) or the PICA (n = 13). The other patients presented with cerebellar tumours (n = 2) and cerebellar agenesis (n = 1). The extent of the cortical lesion (i.e. which lobuli were affected) and possible involvement of the cerebellar nuclei was determined by 3D-MRI. As expected, the ability to acquire classically conditioned eyeblink responses was significantly reduced in the group of all cerebellar patients compared with the controls. In the patients with unilateral cerebellar lesions, conditioning deficits were present ipsilaterally. In SCA patients with lesions including hemispheral lobules VI and Crus I, eyeblink conditioning was significantly reduced on the affected side compared with the unaffected side. No significant difference between the affected and unaffected sides was present in patients with lesions restricted to the common PICA territory (i.e. Crus II and below). Conditioning deficits were neither significantly different in SCA patients with pure cortical lesions compared with SCA patients with additional nuclear impairment nor in SCA patients with unilateral lesions compared with SCA patients with bilateral lesions. To summarize, unilateral cortical lesions of the superior cerebellum appear to be sufficient to reduce eyeblink conditioning in humans significantly.

Dissociation between conflict detection and error monitoring in the human anterior cingulate cortex

The relative importance of the anterior cingulate cortex (ACC) for the detection and resolution of response conflicts versus its role in error monitoring remains under debate. One disputed issue is whether conflict detection and error monitoring can be viewed as unitary functions performed by the same region of the ACC, or whether these processes can be dissociated functionally and anatomically. We used a combination of electrophysiological and neuropsychological methods to assess these competing hypotheses. A neurological patient with a rare focal lesion of rostral-to-middorsal ACC was tested in an event-related potential study designed to track the time course of neural activity during conflicts and erroneous responses. Compared with controls, the error-related negativity component after incorrect responses was attenuated in the patient, accompanied by lower error-correction rates. Conversely, the stimulus-locked component on correct conflict trials, the N450, was enhanced, and behavioral performance was impaired. We hypothesize that intact regions of lateral prefrontal cortex were able to detect response conflict, but damage to the dorsal ACC impaired response inhibition, which may be due to disconnection from cingulate and supplementary motor areas. The results implicate rostral-dorsal ACC in error monitoring and suggest this function can be dissociated from conflict-detection processes.

When writing 0 (zero) is easier than writing O (o): a neuropsychological case study of agraphia

Though a few case studies reported a dissociation between intact writing of Arabic and impaired writing of alphabetical script, a detailed experimental analysis of such a dissociation is still lacking. We report a follow-up study of a patient with a parieto-occipital lesion who is affected by severe peripheral agraphia for letters, but not for Arabic digits. While letters in writing to dictation are frequently illegible, distorted, or consist in meaningless strokes, Arabic digits are well-formed and fluently produced. In a series of tasks, including copying of letters with tachistoscopic presentation and handwriting on a digitizing tablet, several processing levels are assessed in order to localize JS' functional writing impairment and to determine different processing routes for letters and for numbers. Overall, the results of the experimental investigation suggest a notation specific deficit in the activation of graphomotor patterns for letters, but not for digits. The study thus adds evidence to the so far reported dissociations between Arabic and alphabetical scripts.

Neural response to emotional faces with and without awareness: event-related fMRI in a parietal patient with visual extinction and spatial neglect

This study examined whether differential neural responses are evoked by emotional stimuli with and without conscious perception, in a patient with visual neglect and extinction. Stimuli were briefly shown in either right, left, or both fields during event-related fMRI. On bilateral trials, either a fearful or neutral left face appeared with a right house, and it could either be extinguished from awareness or perceived. Seen faces in left visual field (LVF) activated primary visual cortex in the damaged right-hemisphere and bilateral fusiform gyri. Extinguished left faces increased activity in striate and extrastriate cortex, compared with right houses only. Critically, fearful faces activated the left amygdala and extrastriate cortex both when seen and when extinguished; as well as bilateral orbitofrontal and intact right superior parietal areas. Comparison of perceived versus extinguished faces revealed no difference in amygdala for fearful faces. Conscious perception increased activity in fusiform, parietal and prefrontal areas of the left-hemisphere, irrespective of emotional expression; while a differential emotional response to fearful faces occurring specifically with awareness was found in bilateral parietal, temporal, and frontal areas. These results demonstrate that amygdala and orbitofrontal cortex can be activated by emotional stimuli even without awareness after parietal damage; and that substantial unconscious residual processing can occur within spared brain areas well beyond visual cortex, despite neglect and extinction.

Is the middle between both halves?: midpoint location and segment size estimation in neglect

BACKGROUND

Line bisection errors in neglect are attributed to perceptual size distortions. In order to compare the two segments of the line to determine if they are equal, one might first estimate the location of a midpoint that defines the two line segments to be compared.

OBJECTIVES

The authors attempted to determine whether estimating a line's midpoint can be dissociated from comparing the two segments of this line, and if so, what the relative contribution of each of these tasks is to the perceptual bias in neglect.

METHODS

The authors studied two patients with hemispatial neglect from right hemisphere lesions by asking them where bisection marks were placed on prebisected lines and whether the two adjacent line segments were equal.

RESULTS

There was a stronger bias judging the position of the bisecting marks ("where" determination) than comparing the size of two adjacent line segments.

CONCLUSIONS

These results suggest that perceptual size distortion of line segments alone cannot explain the subjects' line bisection bias, but postperceptual deficits in "where" computations may better account for their errors locating the midpoint. "Where" determinations might require more attentional capacity, depend more heavily on viewer-centered allocation of attention, and be mediated by the right hemisphere's "where" dorsal stream. In contrast, comparing the length of two segments might be mediated by the left hemisphere's "what" ventral stream.

Impact of subcortical ischemic lesions on behavior and cognition

Both cerebrovascular disease and AD are common in the elderly. There are various types of underlying damage to tissue and vessels in vascular cognitive impairment, and the neural mechanisms producing cognitive impairment and the clinical picture are different among the subtypes. Among them, small subcortical infarcts disrupting cortico-subcortical circuits and white matter lesions are the commonest types, and the combination of these two types of lesions might be more realistic than each pure form. Moreover, cognitive impairment of vascular origin may be superimposed on AD. Both vascular and degenerative mechanisms contribute to the development of cognitive impairment, especially in old age, whether they are two independent parallel processes or interacting pathologies. Subcortical small lesions involving the thalamus, caudate, and globus pallidus disrupt cortico-subcortical circuits, resulting in cognitive dysfunction. Disruption of the frontal-subcortical circuits leads to cognitive impairment with striking frontal lobe features, and disruption of the memory-related circuits leads to amnesia. White matter changes, which are certainly related to chronic cerebral ischemia in some patients, are another issue. Patients with dementia and white matter changes may have either AD with cerebrovascular changes or a form of VaD, or a combination of these two etiologies. However, our series of studies have suggested that white matter changes in AD patients are superimposed phenomena of vascular origin and that white matter changes contribute to specific neurological and neuropsychiatric manifestations, but not to global cognitive impairment, which is more closely associated with the degenerative process.

[Non-persistent "doll phenomenon" in a patient with right thalamic infarction]

An 81-year-old right-handed woman was admitted because of acute dysarthria and left hemiparesis. She had lived herself without aids until the admission. On neurological examination she was confused and disoriented. She was ambulant, but had mild dysarthria and mild left hemiparesis. Neuropsychological tests showed severe impairment of memory, mild impairment of visual cognition, decreased fluency of word recall and mild paramnesia, but no acalculia, agraphia, aphasia or apraxia. MRI of the brain showed small infarction in the right anterior thalamus. 123I-IMP SPECT demonstrated a decrease in CBF of the thalamus, basal ganglia and frontal lobe on the right. During admission, she always played with a doll as if she took it as a real baby. This peculiar symptom. "doll phenomenon" continued for approximately three months later. The "doll phenomenon" usually appears in demented patients with diffuse mental deterioration or dysfunction of the frontal lobe. The present patient had not been demented until the onset of the thalamic infarction, and disturbance of cognition caused by the right thalamic infarction probably produced the "doll phenomenon".

Task-dependent differences in the exploratory behaviour of patients with spatial neglect

The present study analysed task-dependent effects on the exploratory behaviour of neglect patients during their spontaneous search of the surroundings. We were asking whether different tasks would be associated with different structuring of the visual display and, therefore, would result in different forms of neglect in one and the same brain-damaged subjects. Neglect patients' eye and head movements were recorded when they searched for a target within a homogeneous stimulus array surrounding the subjects. Subsequently, they explored the same array which was now segmented into different areas. When the patients' attention was allocated to the whole surrounding space, all patients completely neglected the left hemispace and spontaneously attended to the right hemispace. No significant left-right asymmetry was detected in a selected segment located in the periphery of the attended, right hemispace. However, all patients completely ignored the left part of this segment when they had to concentrate visual search on this segment alone. The results suggest an important influence of task-dependent effects on the exploratory behaviour of neglect patients. They show that one and the same physical stimulus at one and the same location in a scene might be attended or, in another situation, neglected, just depending on the behavioural goal of the subject. The findings support the idea that the brain organises and reorganises continuously the representation of the same physical input according to the changing task requirements.

The relationship of subcortical MRI hyperintensities and brain volume to cognitive function in vascular dementia

The relationship between MRI findings (i.e., subcortical hyperintensities; SH, whole brain volume) and the cognitive dysfunction of vascular dementia (VaD) was examined. Participants included 24 persons that met NINDS-AIREN criteria for VaD (MMSE = 19.9 +/- 4.2) and underwent comprehensive neuropsychological assessment and MRI brain imaging. The volume of subcortical hyperintensities (SH) was strongly associated with executive-psychomotor performance, but not with performance across other cognitive domains or global cognitive functional level. Conversely, WBV was strongly associated with global cognitive functioning and performance across most cognitive domains (memory, language, visual integration), but not with executive-psychomotor functioning. The failure of SH to account for either the global dementia evident in these VaD patients or impairments across most cognitive domains suggests that deep subcortical white matter disease may only indirectly contribute to the global cognitive dysfunction of VaD. That WBV emerged as a stronger correlate of dementia raises further questions regarding the cerebral mechanisms that contribute to the development of VaD.

[A case of effective antithrombotic therapy for cerebral infarction presenting long-lasting fluctuation of symptoms]

We report a 78-year-old female presenting fluctuation of cerebral ischemic symptoms for a long time. Three weeks after transient ischemic attack of speech disturbance, she suffered right hemiparesis and motor dominant aphasia. The symptoms gradually progressed. Magnetic resonance angiography (MRA) showed a stenosis of branches of the left middle cerebral artery and single photon emission computed tomography (SPECT) did hypoperfusion of the same artery territory. Though antiplatelet and anticoagulant therapy was continued, the symptoms fluctuated. After 5 months, she recovered to mild deficit and MRI finally showed no responsible infarcted area. The pathophysiology of this course was considered to be progressing stroke based on a stenosis of the middle cerebral artery and the atrial fibrillation. Early diagnosis and treatment for cerebral ischemia may lead to the recovery from fluctuating symptoms.

[Knowledge concerning illness, expectations and perceptions of treatment of elderly stroke patients and family caregivers--a prospective study during inpatient treatment]

Forty-five stroke patients and their 45 proxies were interviewed after the patients' hospital admission and before discharge. The topics of the interviews were disease knowledge, expectations in and judgement about therapy, estimation of functional health status (CCOP/WONCA Charts), and prognosis. The patients and proxies were also asked to name the patient's actual three most important health problems. The depressive symptomatology in the patients (geriatric depression scale) and their ADL status (Barthel Index) were evaluated on admission and before hospital discharge. The proxies' general knowledge of disease was superior compared to that of the patients. There were knowledge deficits regarding individual risk factors and secondary prevention, in particular. Information was predominantly obtained from physicians. However, an additional need for information on prognosis and prevention, in particular, was expressed by patients and proxies before hospital discharge. There was a high agreement between the patients and their proxies in mentioning the patients' actual three most important health problems, apart from psychological problems. These were mentioned only by the proxies but not by the patients themselves. Depressive symptomatology in the patients increased significantly. There were associations of depression with the level of the Barthel Index score and the patients' self-estimation of functional health status before and after the stroke. Full recovery was expected by one half of the patients, on admission. The patients' primary therapeutic goal was the ability to walk again. Their ADL status improved significantly, as measured by a mean increase in the Barthel Index score by 22 points. The patients and their proxies, as well, judged the result of treatment equally high. The proxies' total satisfaction with patient care was significantly related to their ratings of separate parts of patient care regarding nurses, therapists, and physicians, to their expectations in therapy, and the satisfaction of their own personal needs. The results of the study revealed a particular need for information on prognosis and secondary prevention of stroke. Furthermore, depression and coping with consequences of the disease should be important issues in counselling of stroke patients and their proxies. The results regarding patient and proxy satisfaction with care were of importance for internal discussion in the clinic.

Cognition and white matter lesions

Although it is recognized that ischemic stroke is a potent risk factor for vascular dementia, the influence of white matter lesions (WML) on cognitive function is less clear. In community-based MRI studies that have administered mental status tests to subjects who were free of clinically evident neurologic disease, a weak relationship between WML and generalized cognitive function has been reported. In studies that have administered neuropsychological test batteries, a stronger and more specific association has been recognized between WML and deficits in executive function, most likely due to the involvement of frontal-subcortical pathways. Cognitive deficits may be related to the total volume of the WML, with a threshold perhaps needing to be surpassed before such deficits are evident, but it is likely that the location of the WML also plays a role, with that threshold varying in association with the distribution of the lesions. Potential confounders of the results of previous studies include small, strategically located subcortical infarctions that may be masked by more extensive WML and other comorbid neurologic disorders, particularly Alzheimer's disease. Future studies should be prospective, utilize standardized methods for structural and functional brain imaging, and administer comprehensive neuropsychological assessments in order to more rigorously investigate the relationship between evolving WML and declining cognitive functions.

[Learning capacity of acute stroke patients. A pilot study]

INTRODUCTION

Acute stroke patients find themselves in a new and totally altered health situation. Several factors add to its complexity. In order to master the health situation as independently as possible, patients must possess the appropriate knowledge. In turn, they must be able to learn. The aim of this study was to answer the question, to which extent will acute stroke patients be able to attain and recall health related and rehabilitation related information. The hypotheses were, that acute stroke patients do possess the ability but that their performance differs, depending on the localization of the lesion and from the performance of non-stroke patients.

METHOD

A convenience sample resulted in 12 participants with hemispheric infarct, eight participants with lacunar infarct and nine participants in a comparison group. By means of structured interview the level of knowledge of all participants was asked, followed by structured teaching and the same structured interview. Five days later the structured interview was carried out again.

RESULTS

The results show that acute stroke patients are able to attain and recall the information offered. Different performance related to the region of lesion and to non-stroke patients could not be proved.

CONCLUSIONS

The ability of acute stroke patients as demonstrated here represents a resource for their rehabilitation during the acute phase. The method and content of structured teaching prevents occasional and inconsistent knowledge transfer. The specific information needs of these patients may not be left disregarded. The information needs of significant others must be taken into account as well. Further research is needed, to lighten up the learning behavior of acute stroke patients and to prove the effect of structured teaching for this group of patients.

Isolated corpus callosal infarction secondary to pericallosal artery disease presenting as alien hand syndrome

Two patients are described with the callosal type of alien hand syndrome. Both presented with abnormal feelings in the left upper limb and intermanual conflict without clinical evidence of callosal apraxia or frontal lobe dysfunction such as motor deficit or reflexive grasping. Imaging studies disclosed subacute infarction in the body and splenium of the corpus callosum due to pericallosal artery disease. These patients were unique in their presentation as a callosal type of alien hand syndrome secondary to ischaemic stroke.

[Maintenance and improvement of quality of life among elderly patients using a pet-type robot]

There have been reports of cases in which quality of life and loneliness of elderly people have been affected by interaction with the pet-type robot AIBO. In the present comparison between first and 20th sessions of activity with the pet-type robot, statistically significant improvements were observed in speech, emotional words and satisfaction index. The AKO loneliness scale value was 3.33 at the first session, and was 1.00 at the 20th session (statistically significant decrease). In a comparison of health-related QOL before and after interaction with AIBO, using the SF-36 survey, role function (RP) was statistically higher at the 20th session than at the first session. Evaluation by CgA, a mental stress index, showed a statistically significant decrease as the number of AIBO sessions increased. Case 1: The patient was a 68-year-old woman with chronic rheumatoid arthritis. Her AKO loneliness scale value was 4 on the first session and 1 on the 20th session. She said, "I do not think about anything while playing with the pet-type robot. It heals my mind." Case 2: The patient was a 74-year-old woman with cervical osteochondrosis. Her AKO loneliness scale value was 5 on the first session and 2 on the 20th session. She said, "The first time, I didn't like playing with the robot because I was depressed. After I had played with the robot several times, I felt good." Case 3: The patient was an 84-year-old man with cerebral apoplexy sequelae. His AKO loneliness scale value was 6 on the first session and 1 on the 20th session. He sang with the robot occasionally. The amount of conversation between him and his children greatly increased. Unlike animals, a pet robot does not carry the risk of bacterial infection. The present results suggest the possibility of using robots as a substitute for animal-assisted therapy and other psychosocial therapy in aseptic rooms, ICUs, children's wards, and special care wards for patients with dementia.

Search pattern in a verbally reported visual scanning test in patients showing spatial neglect

The present study of right hemisphere stroke patients showed that presence of visuospatial neglect in conventional neglect tests at the postacute stage was strongly associated with an aberrant search pattern in a verbally reported visuo-perceptual scanning test. Compared with normal controls, patients with visuospatial neglect showed a greater proportion of repeated readings of the same target, shorter search sequences, more shifts between horizontal, vertical, and diagonal search, and lower proportion of horizontal search. The relation between spatial neglect and a deficient search pattern was strongly influenced by the asymmetric allocation of attention in the scanning test, with the exception for the proportion of repeated reading which was not influenced by this asymmetry. At follow-up, a significant recovery was noted in the neglect group for the proportion of repeated readings and for the asymmetry in the allocation of attention. However, a high number of omitted targets in the search test was still a common finding in the neglect group and it was suggested that a non-lateralized attentional deficit may have played an important role behind the ineffective search at this point of time.

Conversion sensory symptoms associated with parietal lobe infarct: case report, diagnostic issues and brain mechanisms

This case report suggests that diagnostic difficulties and brain mechanisms related to conversion disorder associated with cerebral lesions differ from those related to conversion disorder without cerebral lesions. A 35-year-old divorced woman was admitted to a psychiatric inpatient unit with multiple physical complaints. The symptoms first appeared 5 years previous and 2 months after a sexual assault. Three years later, she began to experience ill-defined sensory symptoms confined to the left half of her body (splitting the midline). Results of neurologic consultations were equivocal because of the subjective nature of the complaints, which were viewed as conversion symptoms. A magnetic resonance imaging scan demonstrated an old infarct in the right parietal lobe, suggesting a physical origin of the patient's symptoms. However, normal somatosensory-evoked responses from the affected area contributed little to establishing the diagnosis. The results of all further investigations to identify causes of the vascular pathology were negative. The multiple ill-defined somatic symptoms, the distribution of sensory symptoms and the resolution of symptoms with psychotherapy established the diagnosis of conversion disorder superimposed on a pre-existing right parietal lesion. This case highlights the importance of clinical features in establishing a diagnosis such as this. We suggest that reactivation of implicit sensory memories (represented at the thalamic level and resulting from decreased corticofugal inhibitions due to the lesion) may contribute to the formation of sensory conversion symptoms in individuals with parietal lobe lesions.

Cognitive dysfunction in recovered depressive patients with silent cerebral infarction

In this study, we characterized cognitive functioning in patients with major depression and silent cerebral infarction (SCI), as detected by magnetic resonance imaging (MRI), after they had recovered from depression. Thirty-five patients with unipolar depression who experienced the onset of depression after the age of 50 underwent MRI and were classified as SCI(+) (n = 17) or SCI(-) (n = 18). The Wechsler Adult Intelligence Scale-Revised (WAIS-R) and the Uchida-Kraepelin psychodiagnostic test were administered after the patients had recovered from depression. In addition, the intelligence quotient (IQ) and mental speed of the patients in the two groups were compared. The total, verbal and performance IQ scores, as determined by the WAIS-R, were significantly lower in the SCI(+) group than in the SCI(-) group. The mental speed of patients in the SCI(+) group, as assessed by the Uchida-Kraepelin psychodiagnostic test, was almost half that of the SCI(-) group. Our findings provide further evidence that a comprehensive impairment of cognitive functioning, especially a severe reduction in mental speed, remains after recovery from depression in patients with major depression and SCI.

Vascular risk factors in late onset mania

BACKGROUND

Previous researches have suggested that late onset mania is a distinct subtype associated with medical and neurological disorders. Few studies, however, have focused on vascular risk factors.

METHODS

Records of 366 bipolar patients were reviewed and age of first psychiatric hospitalization determined. Late-onset cases were determined empirically from a distribution histogram. Late onset cases were matched to early onset cases and histories of vascular disease/risks and current cholesterol levels compared.

RESULTS

The distribution of age of first psychiatric hospitalization was bimodal with an intermode at age 47. Using that threshold, 6.3% of the cohort was classified as having late onset mania. Vascular risks factors were greater and current cholesterol levels higher in the late onset group.

CONCLUSIONS

Late onset mania is associated with greater vascular risk factors. The bimodal appearance of age of first psychiatric hospitalization in this study provides further support of late onset mania as a distinct manic subtype with possibly a different, vascular aetiology. Control of these vascular risks may impact on the incidence of late onset mania, as well as on its clinical management.

[Prognostic factors of cognitive deterioration in patients with cerebral infarcts]

INTRODUCTION

Cognitive deterioration is a frequent finding in patients who have had a cerebral infarct which affected their quality of life. The prognostic factors associated with this are still not completely clear.

OBJECTIVES

To determine the frequency of cognitive deterioration following cerebral infarct and the prognostic factors associated with its appearance.

PATIENTS AND METHODS

We made a study of a prospective pohort in the Hospital Clínico Quirúrgico Hermanos Ameijeiras de Ciudad de La Habana, Cuba, in 401 patients with the confirmed diagnosis of cerebral infarct during the period March 1997 February 2000. A questionnaire was completed for all patients. This contained the possible variables for prognosis. The neuropsychological tests were done 3 and 6 months after the cerebral infarct occurred to determine the appearance of cognitive deterioration. Statistical analysis included the c2 test, relative risk estimation, and multiple logistic regression analysis.

RESULTS

The frequency of cognitive deterioration 3 and 6 months after the cerebral infarct occurred was 22.2% and 6.9% respectively. Multiple logistic regression analysis showed prognostic variables of cognitive deterioration to be arterial hypertension (p=0.001, RR:2.0) and the number of current cerebral infarcts shown on computerized axial tomography (p=0.000, RR:5.2).

CONCLUSIONS

Cognitive deterioration was a frequent complication after a cerebral infarct and several prognostic factors were associated with its appearance.

The role of carotid stenosis in vascular cognitive impairment

The role of carotid stenosis in vascular cognitive impairment was reviewed using Medline, EMBASE, PsychLit and PsychInfo databases using the words "carotid stenosis", "neuropsychological tests" and "endarterectomy". Limited evidence exists for frontal lobe dysfunction associated with carotid stenosis, but there is a lack of systematic and prospective studies carried out in consecutive patients, including appropriate neuropsychological and MRI assessment. Possible pathophysiological processes suggested for cognitive impairment associated with carotid stenosis are suggested; these include chronic ischaemia and lacunar infarction; such mechanisms and resultant pathologies may co-exist in the presence of large-artery atheroma.

Clinical features and treatment response of patients with major depression and silent cerebral infarction

Previously, we reported a relationship between silent cerebral infarction (SCI), as detected by magnetic resonance imaging (MRI), and late onset major depression. In the present study, we clarify the clinical features of the depressive phase of patients with major depression and SCI, and their response to antidepressant pharmacotherapy. Using clinical charts, we retrospectively examined patients with depression, who were first admitted for antidepressant pharmacotherapy. All patients were classified according to the MRI findings and the age on admission (older or younger than 50 years) into either the young SCI(-) group (n = 23), the elderly SCI(-) group (n = 27) or the elderly SCI(+) group (n = 20).The characteristics of the clinical features were evaluated at the time of admission, after 2 weeks of treatment and at the time of discharge using the Hamilton rating scale for depression (HAMD). These data were compared between each patient group. No differences in the clinical features, as evaluated by HAMD, were observed between the three groups at the time of admission. However, the mean length of treatment was significantly longer and the treatment response, as evaluated by the total HAMD score, was significantly worse in the elderly SCI(+) group than in the other two groups, when examined after 2 weeks of treatment and at the time of discharge. The elderly SCI(+) group demonstrated higher scores in feelings of guilt, suicide, retardation and hypochondriasis than the young SCI(-) group and the elderly SCI(-) group after two weeks of treatment, and higher scores in early insomnia, late insomnia, somatic anxiety and hypochondriasis at the time of discharge. Our findings suggest that while the presence of SCI does not affect the clinical features observed at the time of admission, it does affect the treatment response to antidepressant pharmacotherapy.