Michael Kopelman - Academia.edu (original) (raw)
Papers by Michael Kopelman
Brain
There are very few case series of patients with acute psychogenic memory loss (also known as diss... more There are very few case series of patients with acute psychogenic memory loss (also known as dissociative/functional amnesia), and still fewer studies of outcome, or comparisons with neurological memory-disordered patients. Consequently, the literature on psychogenic amnesia is somewhat fragmented and offers little prognostic value for individual patients. In the present study, we reviewed the case records and neuropsychological findings in 53 psychogenic amnesia cases (ratio of 3:1, males:females), in comparison with 21 consecutively recruited neurological memory-disordered patients and 14 healthy control subjects. In particular, we examined the pattern of retrograde amnesia on an assessment of autobiographical memory (the Autobiographical Memory Interview). We found that our patients with psychogenic memory loss fell into four distinct groups, which we categorized as: (i) fugue state; (ii) fugue-to-focal retrograde amnesia; (iii) psychogenic focal retrograde amnesia following a minor neurological episode; and (iv) patients with gaps in their memories. While neurological cases were characterized by relevant neurological symptoms, a history of a past head injury was actually more common in our psychogenic cases (P = 0.012), perhaps reflecting a 'learning episode' predisposing to later psychological amnesia. As anticipated, loss of the sense of personal identity was confined to the psychogenic group. However, clinical depression, family/relationship problems, financial/employment problems, and failure to recognize the family were also statistically more common in that group. The pattern of autobiographical memory loss differed between the psychogenic groups: fugue cases showed a severe and uniform loss of memories for both facts and events across all time periods, whereas the two focal retrograde amnesia groups showed a 'reversed' temporal gradient with relative sparing of recent memories. After 3-6 months, the fugue patients had improved to normal scores for facts and near-normal scores for events. By contrast, the two focal retrograde amnesia groups showed less improvement and continued to show a reversed temporal gradient. In conclusion, the outcome in psychogenic amnesia, particularly those characterized by fugue, is better than generally supposed. Findings are interpreted in terms of Markowitsch's and Kopelman's models of psychogenic amnesia, and with respect to Anderson's neuroimaging findings in memory inhibition.
Cortex, 2007
The present study compared object and action naming in patients with Alzheimer's dementia. We tes... more The present study compared object and action naming in patients with Alzheimer's dementia. We tested the hypothesis put forward in (some) previous studies that in Alzheimer's dementia the production of verbs, that is required in action naming, is better preserved than the production of nouns, that is required in object naming. The possible reason for the dissociation is that verbs are supported predominantly by frontal brain structures that may remain relatively better preserved in early Alzheimer's disease. Objects, on the other hand, are supported by temporal lobe structures that are aVected early in the disease. An alternative hypothesis, which is supported by other studies, is that action naming is more impaired than object naming due to verbs being semantically more complex than nouns. In order to test these contrasting hypotheses, the present study used more stringent methodology than previous studies. We used a larger set of stimuli with carefully matched object and action items and we collected not only accuracy data but also naming latencies, a measure that is sensitive to even mild lexical retrieval problems. We compared the performance of 19 patients with mild to moderate Alzheimer's disease with that of 19 healthy age matched participants. We found that both the patients and the comparison group responded faster and made fewer errors on the object pictures than the action pictures. A qualitative analysis of the naming errors indicated that object and action naming pose diVerent demands for the language system. The results overall suggest that the patients' performance is an exaggeration of the pattern present in the comparison participants.
Brain and Language, 2006
The present study compared object and action naming in patients with Alzheimer's dementia. We tes... more The present study compared object and action naming in patients with Alzheimer's dementia. We tested the hypothesis put forward in (some) previous studies that in Alzheimer's dementia the production of verbs, that is required in action naming, is better preserved than the production of nouns, that is required in object naming. The possible reason for the dissociation is that verbs are supported predominantly by frontal brain structures that may remain relatively better preserved in early Alzheimer's disease. Objects, on the other hand, are supported by temporal lobe structures that are aVected early in the disease. An alternative hypothesis, which is supported by other studies, is that action naming is more impaired than object naming due to verbs being semantically more complex than nouns. In order to test these contrasting hypotheses, the present study used more stringent methodology than previous studies. We used a larger set of stimuli with carefully matched object and action items and we collected not only accuracy data but also naming latencies, a measure that is sensitive to even mild lexical retrieval problems. We compared the performance of 19 patients with mild to moderate Alzheimer's disease with that of 19 healthy age matched participants. We found that both the patients and the comparison group responded faster and made fewer errors on the object pictures than the action pictures. A qualitative analysis of the naming errors indicated that object and action naming pose diVerent demands for the language system. The results overall suggest that the patients' performance is an exaggeration of the pattern present in the comparison participants.
Cortex, 2007
The study addresses the issue of the selective preservation of verbs in Alzheimer's disease (AD).... more The study addresses the issue of the selective preservation of verbs in Alzheimer's disease (AD). Twenty three AD patients and age-matched controls named pictures of objects and actions and took part in a word-picture verification task. The results for picture naming revealed that both patients and controls were faster and produced more target responses for objects than actions. In the comprehension task, accuracy levels were comparable for nouns and verbs, but response times were longer for verbs. Although patients were more error prone and had longer latencies in both tasks than controls, the only qualitative difference in performance between the groups was in response to trials with semantically related foils in the word-picture verification task. Patients were particularly error prone in this condition. We conclude that the results do not provide support for the notion that verbs are selectively preserved in AD. They also do not provide conclusive evidence for claims that depressed naming and comprehension is (always) due to loss of semantic knowledge or inadequate access to semantic knowledge. Finally, we discuss the findings in relation to comparable investigations in patients with semantic dementia.
Cortex, 2007
The study addresses the issue of the selective preservation of verbs in Alzheimer's disease (AD).... more The study addresses the issue of the selective preservation of verbs in Alzheimer's disease (AD). Twenty three AD patients and age-matched controls named pictures of objects and actions and took part in a word-picture verification task. The results for picture naming revealed that both patients and controls were faster and produced more target responses for objects than actions. In the comprehension task, accuracy levels were comparable for nouns and verbs, but response times were longer for verbs. Although patients were more error prone and had longer latencies in both tasks than controls, the only qualitative difference in performance between the groups was in response to trials with semantically related foils in the word-picture verification task. Patients were particularly error prone in this condition. We conclude that the results do not provide support for the notion that verbs are selectively preserved in AD. They also do not provide conclusive evidence for claims that depressed naming and comprehension is (always) due to loss of semantic knowledge or inadequate access to semantic knowledge. Finally, we discuss the findings in relation to comparable investigations in patients with semantic dementia.
The journal of the American Academy of Psychiatry and the Law, 2014
Amnesia for violent offenses is common, but little is known about underlying causes or whether me... more Amnesia for violent offenses is common, but little is known about underlying causes or whether memory can recover. In this study, 50 violent offenders were interviewed with neuropsychological and psychometric measures, to determine the factors that underlie amnesia and the recovery of memory in these cases. The results showed that amnesia for a violent offense was associated with crimes of passion and dissociative symptoms at the time, but not with impaired neuropsychological functioning. Long amnesic gaps were associated with a state of dissociation surrounding the offense and with previous blackouts (whether alcoholic or dissociative). Memory often recovered, either partially or completely, especially where there was a history of blackouts or a lengthy amnesic gap. Brief amnesic gaps were likely to persist, perhaps as a consequence of faulty encoding during a period of extreme emotional arousal (or red-out).
Neuropsychologia, Jan 22, 2014
We present two patients in whom the combination of lesion site and cognitive performance was uniq... more We present two patients in whom the combination of lesion site and cognitive performance was uniquely informative about the organisation and functional anatomy of semantic memory. One had had a single lobar stroke with an unusual distribution, largely destroying the whole of the left temporal lobe ventral to the superior temporal sulcus. The other patient had had herpes simplex encephalitis with destruction that was confined to the left cerebral hemisphere. The lesion again mainly encompassed the left temporal lobe, but also extended to the left inferior frontal gyrus. Cognitive outcomes in the two patients were compared with each other and with published results from patients with semantic dementia. This is because, whereas the majority of semantic dementia patients present with more prominent atrophy of the left rostroventral temporal lobe, they invariably have a degree of atrophy in the mirror region on the right that progresses. Semantic dementia therefore provides no clear evid...
Nature neuroscience, 2001
In standard models, word meanings contribute to reading words aloud and writing them to dictation... more In standard models, word meanings contribute to reading words aloud and writing them to dictation. It is known that categories of knowledge and the associated word meanings can be spared or impaired selectively, but it has not been possible to demonstrate that category-specific effects apply to reading and writing. Here we report the case of a neurodegenerative patient with selectively spared numerical abilities whose brain damage left him able to read and write only number words.
Neuropsychologia, 1997
Patients with focal frontal, temporal lobe, or diencephalic lesions were investigated on measures... more Patients with focal frontal, temporal lobe, or diencephalic lesions were investigated on measures of temporal (recency) and spatial (position) context memory, after manipulating exposure times to match recognition memory for targets (pictorial stimuli) as closely as possible. Patients with diencephalic lesions from an alcoholic Korsak off syndrome showed significant impairment on the temporal context (recency) task, as did patients with
Neuropsychologia, 1999
Patients with focal diencephalic, temporal lobe, or frontal lobe lesions were examinedon various ... more Patients with focal diencephalic, temporal lobe, or frontal lobe lesions were examinedon various measures of remote memory. Korsakoff patients showed a severe impairment with acharacteristic temporal gradient, whereas two patients with focal diencephalic damage (andanterograde amnesia) were virtually unimpaired on remote memory measures. Patients withfrontal lobe pathology were severely impaired in the recall of autobiographical incidents andfamous news events. Patients
Cortex, 2014
Journal homepage: www.elsevier.com/locate/cortex c o r t e x 6 1 ( 2 0 1 4 ) 1 2 7 e1 4 0 http://... more Journal homepage: www.elsevier.com/locate/cortex c o r t e x 6 1 ( 2 0 1 4 ) 1 2 7 e1 4 0 http://dx.difficulty to personalise new sensorimotor information, and an abnormal adherence to premorbid beliefs about the body.
Neuropsychological Rehabilitation, 2014
Anosognosia for hemiplegia (AHP), or unawareness of motor deficits contralateral to a brain lesio... more Anosognosia for hemiplegia (AHP), or unawareness of motor deficits contralateral to a brain lesion, has lasting negative implications for the management and rehabilitation of patients. A recent, bedside psychophysical intervention, namely self-observation by video replay, lead to a lasting remission of severe AHP in an acute stroke patient (Fotopoulou, A., Rudd, A., Holmes, P., & Kopelman, M. ( 2009 ). Self-observation reinstates motor awareness in anosognosia for hemiplegia. Neuropsychologia, 47, 1256-1260). This procedure has been adjusted and applied here, as the basis of two intervention protocols administered independently to two patients with severe AHP. The first study used multiple, successive sessions of video-based self-observation in an acute patient, targeting first the awareness of upper limb and subsequently lower limb paralysis. The second study used a single session of video-based, self- and other-observation in a patient at the chronic stage following onset. Both protocols also involved elements of rapport building and emotional support. The results revealed that video-based self-observation had dramatic, immediate effects on awareness in both acute and chronic stages and it seemed to act as an initial trigger for eventual symptom remission. Nevertheless, these effects did not automatically generalise to all functional domains. This study provides provisional support that video-based self-observation may be included in wider rehabilitation programmes for the management and restoration of anosognosia.
Transfusion Medicine, 2008
A platelet donor may lose 80-100 mL of blood both in the harness and by blood sampling at each do... more A platelet donor may lose 80-100 mL of blood both in the harness and by blood sampling at each donation, the equivalent of four to five whole blood donations per annum for a donor attending at 2-weekly intervals. A 54-year-old male multidose platelet donor had donated platelets at regular 2-weekly intervals for 6 years. He developed an impairment of anterograde memory (new learning). A self-rating scale revealed a moderate degree of depression [Beck Depression Inventory (BDI) score 22]. Memory testing (Doors and People Memory Battery) showed low scores, particularly for verbal recall and verbal recognition memory. He was found to have a normal haemoglobin of 157g L 21 with normal red blood cell indices, but a low serum ferritin (15 ng mL 21 ) and a low serum iron (8Á1 mmol L 21 ). Following iron therapy and a return of his iron stores to normal levels, there was an improved BDI score of 13 (minimal level of depression) and a marked improvement in memory test scores. This has been maintained even though he has resumed platelet donation but at reduced intervals.
Hippocampus, 2003
There are many controversies concerning the structural basis of retrograde amnesia (RA). One view... more There are many controversies concerning the structural basis of retrograde amnesia (RA). One view is that memories are held briefly within a medial temporal store ("hippocampal complex") before being "consolidated" or reorganised within temporal neocortex and/or networks more widely distributed within the cerebral cortex. An alternative view is that the medial temporal lobes are always involved in the storage and retrieval (reactivation) of autobiographical memories (multiple trace theory). The present study used quantitative magnetic resonance imaging (MRI) in 40 patients with focal pathology/volume loss in different sites, to examine the correlates of impairment on three different measures of RA. The findings supported the view that widespread neural networks are involved in the storage and retrieval of autobiographical and other remote memories. Brain volume measures in critical structures could account for 60% of variance on autobiographical memory measures (for incidents and facts) in diencephalic patients and for 60-68% of variance in patients with frontal lesions. Significant correlations with medial temporal lobe volume were found only in the diencephalic group, in whom they were thought to reflect thalamic changes, but not in patients with herpes encephalitis or hypoxia in whom the temporal lobes were particularly implicated. The latter finding fails to support one of the main predictions of multiple trace theory, as presently expounded.
PAIN, 2011
The Authors regret a typographical error occurred in Ref. [41] of the above published article. Th... more The Authors regret a typographical error occurred in Ref. [41] of the above published article. The correct reference is now listed below: [41] Shaffner N, Wittwer A, Kut E, Folkers G, Benninger DH, Candia V. Heat pain threshold and tolerance show no left-right perceptual differences at complementary sites of the human forearm. Neurosci Lett 2008;440:309-13.
Occupational Medicine, 2008
Neuropsychiatric and neuropsychological assessment is increasingly accepted as an accurate evalua... more Neuropsychiatric and neuropsychological assessment is increasingly accepted as an accurate evaluation tool to clarify the performance problems in doctors. Furthermore, it seems that neurocognitive difficulties are commonly found to be the cause for such problems.
Neuropsychology, 2012
Objective: To characterize the numerical profile of patients with acquired brain disorders. Metho... more Objective: To characterize the numerical profile of patients with acquired brain disorders. Method: We investigated numeracy skills in 76 participants-40 healthy controls and 36 patients with neurodegenerative disorders (Alzheimer dementia, frontotemporal dementia, semantic dementia, progressive aphasia) and with focal brain lesions affecting parietal, frontal, and temporal areas as in herpes simplex encephalitis (HSE). All patients were tested with the same comprehensive battery of paper-and-pencil and computerized tasks assessing numerical abilities and calculation. Degenerative and HSE patients also performed nonnumerical semantic tasks. Results: Our results, based on nonparametric group statistics as well as on the analysis of individual patients, and all highly significant, show that: (a) all patients, including those with parietal lesions-a key brain area for numeracy processing-had intact processing of number quantity; (b) patients with impaired semantic knowledge had much better preserved numerical knowledge; and (c) most patients showed impaired calculation skills, with the exception of most semantic dementia and HSE patients. Conclusion: Our results allow us, for the first time, to characterize the numeracy skills in patients with a variety of neurological conditions and to suggest that the pattern of numerical performance can vary considerably across different neurological populations. Moreover, the selective sparing of calculation skills in most semantic dementia and HSE suggest that numerical abilities are an independent component of the semantic system. Finally, our data suggest that, besides the parietal areas, other brain regions might be critical to the understanding and processing of numerical concepts.
Neuropsychological Rehabilitation, 2008
Profound loss of awareness for the past in amnesia has implications for our understanding of memo... more Profound loss of awareness for the past in amnesia has implications for our understanding of memory and belief systems, and how they may become disrupted in neurological conditions. We report the case of CW, a professional musician who became severely amnesic in 1985 following herpes simplex viral encephalitis (HSVE) at the age of 46 years. For many years CW stated several times a day that he had just woken up. He frequently wrote this in his diary too. When shown examples of his diary entries or videos of himself playing or conducting music, he recognised both his handwriting and himself on the video screen but stated vehemently that he "was not conscious then". In a previous paper (Wilson, Baddeley, & Kapur 1995), it was suggested that this lack of awareness for the past was a delusion, defined as a strongly held belief in the face of contradictory evidence (rather than implying any kind of psychiatric disorder per se). As a contribution to the academic debate regarding theories of "self", in the present paper we will review this explanation of CW's state as it had been in those early years, and we will also consider two other possibilities - namely, that CW had suffered from a loss of "autobiographical self" or "extended consciousness" (see Damasio, 2000, pp. 198-199), and that his verbal reports simply reflected a form of coping strategy to help him deal with the limited evidence he had available in "declarative" memory.
Brain
There are very few case series of patients with acute psychogenic memory loss (also known as diss... more There are very few case series of patients with acute psychogenic memory loss (also known as dissociative/functional amnesia), and still fewer studies of outcome, or comparisons with neurological memory-disordered patients. Consequently, the literature on psychogenic amnesia is somewhat fragmented and offers little prognostic value for individual patients. In the present study, we reviewed the case records and neuropsychological findings in 53 psychogenic amnesia cases (ratio of 3:1, males:females), in comparison with 21 consecutively recruited neurological memory-disordered patients and 14 healthy control subjects. In particular, we examined the pattern of retrograde amnesia on an assessment of autobiographical memory (the Autobiographical Memory Interview). We found that our patients with psychogenic memory loss fell into four distinct groups, which we categorized as: (i) fugue state; (ii) fugue-to-focal retrograde amnesia; (iii) psychogenic focal retrograde amnesia following a minor neurological episode; and (iv) patients with gaps in their memories. While neurological cases were characterized by relevant neurological symptoms, a history of a past head injury was actually more common in our psychogenic cases (P = 0.012), perhaps reflecting a 'learning episode' predisposing to later psychological amnesia. As anticipated, loss of the sense of personal identity was confined to the psychogenic group. However, clinical depression, family/relationship problems, financial/employment problems, and failure to recognize the family were also statistically more common in that group. The pattern of autobiographical memory loss differed between the psychogenic groups: fugue cases showed a severe and uniform loss of memories for both facts and events across all time periods, whereas the two focal retrograde amnesia groups showed a 'reversed' temporal gradient with relative sparing of recent memories. After 3-6 months, the fugue patients had improved to normal scores for facts and near-normal scores for events. By contrast, the two focal retrograde amnesia groups showed less improvement and continued to show a reversed temporal gradient. In conclusion, the outcome in psychogenic amnesia, particularly those characterized by fugue, is better than generally supposed. Findings are interpreted in terms of Markowitsch's and Kopelman's models of psychogenic amnesia, and with respect to Anderson's neuroimaging findings in memory inhibition.
Cortex, 2007
The present study compared object and action naming in patients with Alzheimer's dementia. We tes... more The present study compared object and action naming in patients with Alzheimer's dementia. We tested the hypothesis put forward in (some) previous studies that in Alzheimer's dementia the production of verbs, that is required in action naming, is better preserved than the production of nouns, that is required in object naming. The possible reason for the dissociation is that verbs are supported predominantly by frontal brain structures that may remain relatively better preserved in early Alzheimer's disease. Objects, on the other hand, are supported by temporal lobe structures that are aVected early in the disease. An alternative hypothesis, which is supported by other studies, is that action naming is more impaired than object naming due to verbs being semantically more complex than nouns. In order to test these contrasting hypotheses, the present study used more stringent methodology than previous studies. We used a larger set of stimuli with carefully matched object and action items and we collected not only accuracy data but also naming latencies, a measure that is sensitive to even mild lexical retrieval problems. We compared the performance of 19 patients with mild to moderate Alzheimer's disease with that of 19 healthy age matched participants. We found that both the patients and the comparison group responded faster and made fewer errors on the object pictures than the action pictures. A qualitative analysis of the naming errors indicated that object and action naming pose diVerent demands for the language system. The results overall suggest that the patients' performance is an exaggeration of the pattern present in the comparison participants.
Brain and Language, 2006
The present study compared object and action naming in patients with Alzheimer's dementia. We tes... more The present study compared object and action naming in patients with Alzheimer's dementia. We tested the hypothesis put forward in (some) previous studies that in Alzheimer's dementia the production of verbs, that is required in action naming, is better preserved than the production of nouns, that is required in object naming. The possible reason for the dissociation is that verbs are supported predominantly by frontal brain structures that may remain relatively better preserved in early Alzheimer's disease. Objects, on the other hand, are supported by temporal lobe structures that are aVected early in the disease. An alternative hypothesis, which is supported by other studies, is that action naming is more impaired than object naming due to verbs being semantically more complex than nouns. In order to test these contrasting hypotheses, the present study used more stringent methodology than previous studies. We used a larger set of stimuli with carefully matched object and action items and we collected not only accuracy data but also naming latencies, a measure that is sensitive to even mild lexical retrieval problems. We compared the performance of 19 patients with mild to moderate Alzheimer's disease with that of 19 healthy age matched participants. We found that both the patients and the comparison group responded faster and made fewer errors on the object pictures than the action pictures. A qualitative analysis of the naming errors indicated that object and action naming pose diVerent demands for the language system. The results overall suggest that the patients' performance is an exaggeration of the pattern present in the comparison participants.
Cortex, 2007
The study addresses the issue of the selective preservation of verbs in Alzheimer's disease (AD).... more The study addresses the issue of the selective preservation of verbs in Alzheimer's disease (AD). Twenty three AD patients and age-matched controls named pictures of objects and actions and took part in a word-picture verification task. The results for picture naming revealed that both patients and controls were faster and produced more target responses for objects than actions. In the comprehension task, accuracy levels were comparable for nouns and verbs, but response times were longer for verbs. Although patients were more error prone and had longer latencies in both tasks than controls, the only qualitative difference in performance between the groups was in response to trials with semantically related foils in the word-picture verification task. Patients were particularly error prone in this condition. We conclude that the results do not provide support for the notion that verbs are selectively preserved in AD. They also do not provide conclusive evidence for claims that depressed naming and comprehension is (always) due to loss of semantic knowledge or inadequate access to semantic knowledge. Finally, we discuss the findings in relation to comparable investigations in patients with semantic dementia.
Cortex, 2007
The study addresses the issue of the selective preservation of verbs in Alzheimer's disease (AD).... more The study addresses the issue of the selective preservation of verbs in Alzheimer's disease (AD). Twenty three AD patients and age-matched controls named pictures of objects and actions and took part in a word-picture verification task. The results for picture naming revealed that both patients and controls were faster and produced more target responses for objects than actions. In the comprehension task, accuracy levels were comparable for nouns and verbs, but response times were longer for verbs. Although patients were more error prone and had longer latencies in both tasks than controls, the only qualitative difference in performance between the groups was in response to trials with semantically related foils in the word-picture verification task. Patients were particularly error prone in this condition. We conclude that the results do not provide support for the notion that verbs are selectively preserved in AD. They also do not provide conclusive evidence for claims that depressed naming and comprehension is (always) due to loss of semantic knowledge or inadequate access to semantic knowledge. Finally, we discuss the findings in relation to comparable investigations in patients with semantic dementia.
The journal of the American Academy of Psychiatry and the Law, 2014
Amnesia for violent offenses is common, but little is known about underlying causes or whether me... more Amnesia for violent offenses is common, but little is known about underlying causes or whether memory can recover. In this study, 50 violent offenders were interviewed with neuropsychological and psychometric measures, to determine the factors that underlie amnesia and the recovery of memory in these cases. The results showed that amnesia for a violent offense was associated with crimes of passion and dissociative symptoms at the time, but not with impaired neuropsychological functioning. Long amnesic gaps were associated with a state of dissociation surrounding the offense and with previous blackouts (whether alcoholic or dissociative). Memory often recovered, either partially or completely, especially where there was a history of blackouts or a lengthy amnesic gap. Brief amnesic gaps were likely to persist, perhaps as a consequence of faulty encoding during a period of extreme emotional arousal (or red-out).
Neuropsychologia, Jan 22, 2014
We present two patients in whom the combination of lesion site and cognitive performance was uniq... more We present two patients in whom the combination of lesion site and cognitive performance was uniquely informative about the organisation and functional anatomy of semantic memory. One had had a single lobar stroke with an unusual distribution, largely destroying the whole of the left temporal lobe ventral to the superior temporal sulcus. The other patient had had herpes simplex encephalitis with destruction that was confined to the left cerebral hemisphere. The lesion again mainly encompassed the left temporal lobe, but also extended to the left inferior frontal gyrus. Cognitive outcomes in the two patients were compared with each other and with published results from patients with semantic dementia. This is because, whereas the majority of semantic dementia patients present with more prominent atrophy of the left rostroventral temporal lobe, they invariably have a degree of atrophy in the mirror region on the right that progresses. Semantic dementia therefore provides no clear evid...
Nature neuroscience, 2001
In standard models, word meanings contribute to reading words aloud and writing them to dictation... more In standard models, word meanings contribute to reading words aloud and writing them to dictation. It is known that categories of knowledge and the associated word meanings can be spared or impaired selectively, but it has not been possible to demonstrate that category-specific effects apply to reading and writing. Here we report the case of a neurodegenerative patient with selectively spared numerical abilities whose brain damage left him able to read and write only number words.
Neuropsychologia, 1997
Patients with focal frontal, temporal lobe, or diencephalic lesions were investigated on measures... more Patients with focal frontal, temporal lobe, or diencephalic lesions were investigated on measures of temporal (recency) and spatial (position) context memory, after manipulating exposure times to match recognition memory for targets (pictorial stimuli) as closely as possible. Patients with diencephalic lesions from an alcoholic Korsak off syndrome showed significant impairment on the temporal context (recency) task, as did patients with
Neuropsychologia, 1999
Patients with focal diencephalic, temporal lobe, or frontal lobe lesions were examinedon various ... more Patients with focal diencephalic, temporal lobe, or frontal lobe lesions were examinedon various measures of remote memory. Korsakoff patients showed a severe impairment with acharacteristic temporal gradient, whereas two patients with focal diencephalic damage (andanterograde amnesia) were virtually unimpaired on remote memory measures. Patients withfrontal lobe pathology were severely impaired in the recall of autobiographical incidents andfamous news events. Patients
Cortex, 2014
Journal homepage: www.elsevier.com/locate/cortex c o r t e x 6 1 ( 2 0 1 4 ) 1 2 7 e1 4 0 http://... more Journal homepage: www.elsevier.com/locate/cortex c o r t e x 6 1 ( 2 0 1 4 ) 1 2 7 e1 4 0 http://dx.difficulty to personalise new sensorimotor information, and an abnormal adherence to premorbid beliefs about the body.
Neuropsychological Rehabilitation, 2014
Anosognosia for hemiplegia (AHP), or unawareness of motor deficits contralateral to a brain lesio... more Anosognosia for hemiplegia (AHP), or unawareness of motor deficits contralateral to a brain lesion, has lasting negative implications for the management and rehabilitation of patients. A recent, bedside psychophysical intervention, namely self-observation by video replay, lead to a lasting remission of severe AHP in an acute stroke patient (Fotopoulou, A., Rudd, A., Holmes, P., & Kopelman, M. ( 2009 ). Self-observation reinstates motor awareness in anosognosia for hemiplegia. Neuropsychologia, 47, 1256-1260). This procedure has been adjusted and applied here, as the basis of two intervention protocols administered independently to two patients with severe AHP. The first study used multiple, successive sessions of video-based self-observation in an acute patient, targeting first the awareness of upper limb and subsequently lower limb paralysis. The second study used a single session of video-based, self- and other-observation in a patient at the chronic stage following onset. Both protocols also involved elements of rapport building and emotional support. The results revealed that video-based self-observation had dramatic, immediate effects on awareness in both acute and chronic stages and it seemed to act as an initial trigger for eventual symptom remission. Nevertheless, these effects did not automatically generalise to all functional domains. This study provides provisional support that video-based self-observation may be included in wider rehabilitation programmes for the management and restoration of anosognosia.
Transfusion Medicine, 2008
A platelet donor may lose 80-100 mL of blood both in the harness and by blood sampling at each do... more A platelet donor may lose 80-100 mL of blood both in the harness and by blood sampling at each donation, the equivalent of four to five whole blood donations per annum for a donor attending at 2-weekly intervals. A 54-year-old male multidose platelet donor had donated platelets at regular 2-weekly intervals for 6 years. He developed an impairment of anterograde memory (new learning). A self-rating scale revealed a moderate degree of depression [Beck Depression Inventory (BDI) score 22]. Memory testing (Doors and People Memory Battery) showed low scores, particularly for verbal recall and verbal recognition memory. He was found to have a normal haemoglobin of 157g L 21 with normal red blood cell indices, but a low serum ferritin (15 ng mL 21 ) and a low serum iron (8Á1 mmol L 21 ). Following iron therapy and a return of his iron stores to normal levels, there was an improved BDI score of 13 (minimal level of depression) and a marked improvement in memory test scores. This has been maintained even though he has resumed platelet donation but at reduced intervals.
Hippocampus, 2003
There are many controversies concerning the structural basis of retrograde amnesia (RA). One view... more There are many controversies concerning the structural basis of retrograde amnesia (RA). One view is that memories are held briefly within a medial temporal store ("hippocampal complex") before being "consolidated" or reorganised within temporal neocortex and/or networks more widely distributed within the cerebral cortex. An alternative view is that the medial temporal lobes are always involved in the storage and retrieval (reactivation) of autobiographical memories (multiple trace theory). The present study used quantitative magnetic resonance imaging (MRI) in 40 patients with focal pathology/volume loss in different sites, to examine the correlates of impairment on three different measures of RA. The findings supported the view that widespread neural networks are involved in the storage and retrieval of autobiographical and other remote memories. Brain volume measures in critical structures could account for 60% of variance on autobiographical memory measures (for incidents and facts) in diencephalic patients and for 60-68% of variance in patients with frontal lesions. Significant correlations with medial temporal lobe volume were found only in the diencephalic group, in whom they were thought to reflect thalamic changes, but not in patients with herpes encephalitis or hypoxia in whom the temporal lobes were particularly implicated. The latter finding fails to support one of the main predictions of multiple trace theory, as presently expounded.
PAIN, 2011
The Authors regret a typographical error occurred in Ref. [41] of the above published article. Th... more The Authors regret a typographical error occurred in Ref. [41] of the above published article. The correct reference is now listed below: [41] Shaffner N, Wittwer A, Kut E, Folkers G, Benninger DH, Candia V. Heat pain threshold and tolerance show no left-right perceptual differences at complementary sites of the human forearm. Neurosci Lett 2008;440:309-13.
Occupational Medicine, 2008
Neuropsychiatric and neuropsychological assessment is increasingly accepted as an accurate evalua... more Neuropsychiatric and neuropsychological assessment is increasingly accepted as an accurate evaluation tool to clarify the performance problems in doctors. Furthermore, it seems that neurocognitive difficulties are commonly found to be the cause for such problems.
Neuropsychology, 2012
Objective: To characterize the numerical profile of patients with acquired brain disorders. Metho... more Objective: To characterize the numerical profile of patients with acquired brain disorders. Method: We investigated numeracy skills in 76 participants-40 healthy controls and 36 patients with neurodegenerative disorders (Alzheimer dementia, frontotemporal dementia, semantic dementia, progressive aphasia) and with focal brain lesions affecting parietal, frontal, and temporal areas as in herpes simplex encephalitis (HSE). All patients were tested with the same comprehensive battery of paper-and-pencil and computerized tasks assessing numerical abilities and calculation. Degenerative and HSE patients also performed nonnumerical semantic tasks. Results: Our results, based on nonparametric group statistics as well as on the analysis of individual patients, and all highly significant, show that: (a) all patients, including those with parietal lesions-a key brain area for numeracy processing-had intact processing of number quantity; (b) patients with impaired semantic knowledge had much better preserved numerical knowledge; and (c) most patients showed impaired calculation skills, with the exception of most semantic dementia and HSE patients. Conclusion: Our results allow us, for the first time, to characterize the numeracy skills in patients with a variety of neurological conditions and to suggest that the pattern of numerical performance can vary considerably across different neurological populations. Moreover, the selective sparing of calculation skills in most semantic dementia and HSE suggest that numerical abilities are an independent component of the semantic system. Finally, our data suggest that, besides the parietal areas, other brain regions might be critical to the understanding and processing of numerical concepts.
Neuropsychological Rehabilitation, 2008
Profound loss of awareness for the past in amnesia has implications for our understanding of memo... more Profound loss of awareness for the past in amnesia has implications for our understanding of memory and belief systems, and how they may become disrupted in neurological conditions. We report the case of CW, a professional musician who became severely amnesic in 1985 following herpes simplex viral encephalitis (HSVE) at the age of 46 years. For many years CW stated several times a day that he had just woken up. He frequently wrote this in his diary too. When shown examples of his diary entries or videos of himself playing or conducting music, he recognised both his handwriting and himself on the video screen but stated vehemently that he "was not conscious then". In a previous paper (Wilson, Baddeley, & Kapur 1995), it was suggested that this lack of awareness for the past was a delusion, defined as a strongly held belief in the face of contradictory evidence (rather than implying any kind of psychiatric disorder per se). As a contribution to the academic debate regarding theories of "self", in the present paper we will review this explanation of CW's state as it had been in those early years, and we will also consider two other possibilities - namely, that CW had suffered from a loss of "autobiographical self" or "extended consciousness" (see Damasio, 2000, pp. 198-199), and that his verbal reports simply reflected a form of coping strategy to help him deal with the limited evidence he had available in "declarative" memory.