Long-Term Cognitive Sequelae of Cerebral Malaria in Vietnam Veterans

The brains of fatal cases of cerebral malaria exhibit capillary occlusion, punctiform hemorrhages, and focal necrosis in subcortical white matter. Some studies have suggested that the brain pathology of survivors is similar to that of fatal cases. The purpose of this study was to investigate the hypothesis that cerebral malaria survivors would exhibit neuropsychological impairment due to the residual cerebral damage sustained from the infection. Vietnam veterans reporting a history of cerebral malaria were compared with a group of veterans with a history of combat-related injuries on standard neuropsychological tasks and on dichotic listening (DL). The cerebral malaria group performed worse on memory tasks and exhibited greater clinical impairments on DL, consistent with presumed disruption of subcortical white matter tracts.

Theta bursts, closed head injury, and partial seizure-like symptoms: a retrospective study

The purpose of this retrospective, chart-review study was to provide additional information on the clinical correlates ofparoxysmal theta activity on EEG and to further examine the previously proposed relation (Varney, Hines, Bailey, & Roberts, 1992) between episodic symptoms in the context of prior closed-head injury and theta bursts. Allparticipants were veterans receiving their health care at a single, tertiary-care, Veterans Affairs medical center. Compared with patients with normal EEGs (comparison group, n = 30) and nonparoxysmal theta-delta slowing (comparison group, n = 30), consecutive patients with theta bursts (n = 38) were found to have significantly more episodic (ie., partial seizure-like) symptoms documented in their medical records. History of closed-head trauma was also associated with increased reporting of episodic symptoms across all three clinical groups. These findings suggest that, in the presence of theta bursts on EEG, clinicians may wish to interview systematicallyfor episodic, partial seizure-like phenomena, especially when paroxysmal theta activity occurs in the context of prior closed head injury.

Can head injury patients simulate malingering?

In the past few years, there have been many simulation studies on the efficacy of symptom validation tests. These typically involved nonclinical participants. This line of research was limited because the impact of the experience of head injury was not examined. Researchers failed to understand whether individuals with head injury would feign cognitive deficits on symptom validation tests as well as their nonclinical counterparts did. This study was designed to investigate simulation of memory deficits among the head injured on the Portland Digit Recognition Test (PDRT; Binder, 1993). Head injury patients, with and without corroborated brain damage, and a group of controls were involved to resemble clinical populations. Results showed that false negative rates ranged from 67% to 84% when participants were asked to feign memory difficulty on the PDRT. Head injury patients, regardless of corroboration of brain damage, were equally capable of feigning memory deficits on the PDRT as their nonclinical counterparts. Findings suggest that the additive value of symptom validity tests, such as the PDRT, can be limited for their use as malingering tests.

Quantitative PET findings in patients with posttraumatic anosmia

OBJECTIVE

To investigate quantitative positron emission tomography (PET) findings, particularly from orbitofrontal cortex, in patients with posttraumatic anosmia.

SETTING

Neuropsychology outpatient clinic and university brain imaging center.

SUBJECTS

Eleven patients with head injury resulting in severe anosmia and 11 controls matched for age. All 11 head-injured patients had their head injuries at least 2 years before involvement in the study.

MEASURES

Regional cerebral glucose metabolism was measured with PET.

RESULTS

Quantitative evaluation of PET findings for anosmic patients as a group showed orbitofrontal hypometabolism compared with controls. Decreased activity was also noted in mesial temporal lobe. Activity in subcortical white matter was essentially identical between groups.

CONCLUSIONS

Findings strongly suggest that posttraumatic anosmia is closely associated with hypometabolism in the orbitofrontal cortex and the medial prefrontal cortex. The results also underscore the importance of posttraumatic anosmia as a clinical sign of orbitofrontal damage, as has been shown previously with neuroSPECT (single photon emission computed tomography).

Quantitative PET scan findings in carbon monoxide poisoning: deficits seen in a matched pair

Quantitative positron emission tomography (PET) was utilized to establish the degree and localization of central nervous system dysfunction in 2 adult patients 3 years status postchronic carbon monoxide poisoning. The individual PET scans were compared against a composite scan made up of 32 normals using a z transformation statistical parametric map. Neuropsychological findings indicated marked anterior frontal lobe syndrome in the context of far-above-average intelligence, memory, and language. They also showed manifest frontal symptoms in activities of daily living that resulted in vocational disability in each case. PET analysis revealed substantially decreased metabolism in the orbitofrontal and dorsolateral prefrontal cortex as well as in areas of the temporal lobe for each individual. Individual scans were very similar and consistent with patient's presenting symptoms, and changed life circumstances. This report represents the first quantitative functional neuroimaging study relevant to carbon monoxide poisoning.

Long-term neuropsychological sequelae of severe burns

Eight patients who suffered severe burns and protracted periods of amnesia following those burns were evaluated for neuropsychological and neuropsychiatric problems between 6 months and 4 years following their accidents. All were found to have significant problems as evidenced in neuropsychological testing, activities of daily living, and reports from relatives. Findings on these burn patients with postburn amnesia were quite different from those of five burn patients who did not develop amnesia. Problems observed and reported in the burn-amnesia patients appeared to reflect clear neuropathological etiologies, which was not unexpected because their initial amnestic syndromes must also have been the result of significant central nervous system dysfunction. It is recommended that severe burn patients have neuropsychological, psychiatric, and neurological exams as part of routine postburn care.

PET Scan Findings in a Patient With a Remote History of Exposure to Organic Solvents

This is a single-case study employing positron emission tomography (PET) scanning and neuropsychological assessment on a 47-year-old male with a 15-year history of repeated respiratory and dermal exposure to high levels of organic solvents with at least 750 peak exposures (i.e., solvent "intoxication"). At age 43, he presented with neuropsychological symptoms of a solvent encephalopathy and multiple abnormalities in his peripheral neurological examination but had normal MRI and EEG findings. Four years after cessation of exposure to degreasing and solvent chemicals, the patient produced a grossly abnormal PET scan in which frontal, hippocampal, and parietal hypometabolism were particularly noteworthy. During this same 4-year period of nonexposure, modest improvements in neuropsychological testing were noted, along with substantial improvements in partial seizurelike symptoms. Frontal lobe deficits elicited in testing and from collateral interview, however, did not change. Findings suggest that repeated peak exposures to organic solvents m y result in a neurobehaviorally complex solvent syndrome caused by central nervous system damage that is readily apparent on PET scan, even though it is not evident in either imaging technologies. In addition, the case is the first reported in which functional neuroimaging was employed to study a patient with chronic solvent encephalopathy many years after cessation of solvent exposure.

NeuroSPECT findings in patients with posttraumatic anosmia: a quantitative analysis

OBJECTIVE

To investigate quantitative neuroSPECT findings, particularly from orbital frontal cortex, in patients rendered totally anosmic from head injury.

SETTING

Veterans Administration (VA) Medical Center.

SUBJECTS

Eighteen patients with head injury resulting in severe anosmia and five normal controls. All 18 patients had sustained their head injuries at least 5 years prior to involvement in the study.

MEASURES

Quantitative neuroSPECT (count density) from sagittal regions of interest (ROIs) ranging circumferentially from orbital frontal cortex to occipital pole.

RESULTS

Quantitative evaluation of neuroSPECT findings for anosmic patients as a group showed substantial orbital frontal hypoperfusion compared with controls, with 67% of individual anosmic patients showing orbital frontal hypoperfusion at a level two or more standard deviations below that of the worst control subject. By contrast, there were no between-group differences for five other ROIs (inferior frontal pole, superior frontal pole, posterior superior frontal lobe, the parasagittal region, and occipital pole), and individual abnormalities were infrequent in these areas. In addition, orbital frontal count was significantly correlated with ratings of outcome, the only ROI to have such a relationship.

CONCLUSIONS

Findings strongly suggest that posttraumatic anosmia and the neuropsychological deficits typically associated with posttraumatic anosmia are closely and specifically associated with hypoperfusion in orbital frontal cortex. The results also underscore the importance of posttraumatic anosmia as a clinical sign of orbital frontal damage, which is particularly important in patients with mild head injury who have normal computed tomography and magnetic resonance imaging scans.

Neuropsychiatric sequelae of cerebral malaria in Vietnam veterans

Approximately 250,000 Vietnam veterans suffered cerebral malaria, an illness that often results in damage to subcortical white matter and fronto-temporal areas of neocortex. Case reports dating back 2500 years indicate that survivors of cerebral malaria show depression, poor memory, personality change, and irritability/violence. The purpose of the present study was to compare the neuropsychiatric status of Vietnam veterans who had suffered cerebral malaria in the remote past (i.e., 1966 to 1969) with that of Vietnam veterans wounded in combat who had not suffered malaria or other neurological conditions. Findings indicate that cerebral malaria results in multiple, major, substantially underappreciated neuropsychiatric symptoms in Vietnam veterans, including poor dichotic listening, "personality change," depression, and, in some cases, partial seizure-like symptoms. Findings strongly suggest that history of malaria should be considered in any medical, psychological, or psychiatric workup of a Vietnam War veteran because a positive response could result in substantial changes in diagnosis and treatment.

A case of reversible steroid dementia

Psychotropic effects of corticosteroids have been reported since early 1950. Dementia-like cognitive changes in patients undergoing treatment with high doses of corticosteroids were identified in 1984. The clinical presentation of these "steroid dementia" patients mimicked those typical of early Alzheimer's disease. As with psychiatric side effects of corticosteroid use, the "dementia" is reversible. The case presented describes a patient who developed dementia-like cognitive changes and an abnormal EEG as a result of steroid treatment. The case is of interest not only as an example of steroid dementia, but also because it is the first with documented electroencephalographic sequelae and premorbid EEG, CT scan and neuropsychological testing.

Design fluency among normals and patients with closed head injury

A Design Fluency task was administered to 86 patients who had suffered closed head injury (CHI) with loss of consciousness and 87 normal control subjects. Subjects were asked to draw as many novel designs as they could in 5 minutes without scribbling, drawing a nameable object, or repeating a design that had been drawn previously. The mean performance of the CHI group was significantly poorer than that of the control group, with 47% of head injured performing defectively (below the 5th percentile of controls There was no significant relationship between Design Fluency and prorated IQ, psychomotor speed, or Word Fluency. The findings demonstrate that a standardized version of the "free condition" of Design Fluency is likely to be useful in the evaluation of patients with closed head injury.

Brain injury without head injury. Some physics of automobile collisions with particular reference to brain injuries occurring without physical head trauma

The classic kinematic formula, a=(v2-v0(2))/2s, relating deceleration to change of velocity and displacement during the change, is used to determine the acceleration experienced by the occupants of motor vehicles (and their heads) during collisions. The displacement, s, of the occupants in the accident can often be determined from the deformation of the wreckage, thus yielding this critical information about potential for brain injury. Data from 15 accidents are assembled and approximate accelerations computed. At the same time medical and neuropsychological data have been obtained for each of the accident victims. These accidents and the associated victims (except for one special case) have been selected because in no case has the victim suffered a direct head-contact injury. Nevertheless, all suffered neurologic and/or neuropsychological injuries typical of patients with closed head trauma. The paper demonstrates that with decelerations from 30 g to more than 200 g yet without skull impacts, brain damage results.

Characteristics and mechanisms of epilepsy spectrum disorder: an explanatory model

Recently, a complex neurobehavioral disorder with paroxysmal affective, psychosensory, and cognitive symptoms has been described by a number of different neuropsychiatric and neuropsychological practitioners. Although a variety of different terms have been used to characterize this clinical entity, the recently coined term epilepsy spectrum disorder (ESD) will be used for the purposes of this article. The clinical identification, neuropsychological characteristics, differential diagnosis, etiology, and treatment response of such patients will be reviewed. The possible neuropathological and neurophysiological mechanisms underlying ESD and implications for future research will also be discussed It is argued that neuropsychologists should be more familiar with this syndrome because such patients are frequently referred for neuropsychological assessment when practitioners from medical disciplines are confused by the atypical and polysymptomatic clinical presentations of ESD patients.

Significance of unilateral ear extinction on the dichotic listening test

The association between unilateral ear extinction on the dichotic listening test and the lateralization of epileptogenic foci was examined in a sample of 49 seizure patients undergoing preoperative evaluation for epilepsy surgery. Results from patients who were left hemisphere dominant for speech indicated that right ear impairment was always predictive of a unilateral left hemisphere focus, but left ear extinction was associated with unilateral lesions of either hemisphere. In this patient sample, dichotic listening performance reflected an interaction of both lateralized foci and hemispheric preference of language processing. Implications concerning clinical use of the dichotic listening test are discussed.

Do dichotic word listening asymmetries predict side of temporal lobe seizure onset?

Dichotic word listening asymmetries are thought to be useful in predicting side of temporal lobe dysfunction. However, little direct evidence exists to support this assumption in practice, especially in patients with subtle epileptogenic lesions. To determine if word listening ear asymmetries are valid predictors of side of temporal lobe seizure onset, we examined the preoperative dichotic word listening performance of 80 patients with either left (N = 41) or right (N = 39) temporal lobe (TL) seizure foci. On a group level, patients showed a statistically significant 'lesion effect' as evidenced by a relative deficit in the ear contralateral to the side of lesion. Prediction of side of seizure focus in individual cases, however, was poor: depending upon the criteria used, 61% to 80% of epileptics with unilateral temporal lobe foci did not show the expected contralateral ear deficit. Results suggest that caution be exercised when inferring side of temporal lobe seizure focus through dichotic word listening asymmetries in individual temporal lobe epilepsy cases.

Long-term neuropsychological sequelae of fever associated with amnesia

It has been well established that high fever can cause substantial damage to the cerebellum and also cause multiple small vascular lesions in neocortex and subcortical white matter. Beyond acute effects, the neuropsychological sequelae of these latter cortical and subcortical lesions have not been studied. The investigation reported involved 36 VA patients with a history of serious febrile illness. The febrile illnesses of the pyrexic subjects did not cause febrile seizures and resulted from diseases that did not directly involve the brain (e.g., encephalitis, meningitis, malaria). Control subjects were combat veterans who had suffered gunshot wounds, but who had no history of febrile illness. Pyrexic patients performed worse than controls on a variety of measures including language, memory, concentration, and word finding as well as failing a test of dichotic listening for words. Results demonstrate that hyperpyrexia can have lasting neuropsychological sequelae, and suggest that history of serious febrile illness be considered as an exclusionary criterion for participation in neuropsychological research concerning other topics or disorders.

Identification of treatment-resistant depressives who respond favorably to carbamazepine

Thirteen depressed patients with documented histories of failure to respond to tricyclic antidepressant medications who reported multiple partial seizure like symptoms were given open trials of carbamazepine. Eleven of the 13 showed moderate to substantial improvement in affective status that was accompanied by significant mean changes on the Beck or Hamilton depression scales. In addition, the mean number of reported partial seizure-like symptoms decreased significantly with treatment. Dichotic word listening performance was the only neuropsychological variable that was impaired at baseline and was also the only cognitive performance that improved following treatment. These preliminary observations suggest that there is likely to be a subgroup of treatment-resistant, carbamazepine-responsive depressives who can be identified by evaluating for the presence of multiple partial seizure-like symptoms.

Neuropsychologic dysfunction in women following leuprolide acetate induction of hypoestrogenism

OBJECTIVE

The study investigated the neuropsychological status of women with induced hypoestrogenism.

DESIGN

An ABA design was employed in which neuropsychological measures were repeated prior to, during, and after induction of hypoestrogenism with leuprolide acetate.

SETTING

The study took place in a medical school affiliated in vitro fertilization clinic.

INTERVENTIONS

Leuprolide acetate was administered to all subjects as part of in vitro fertilization.

METHODS

Eighteen women receiving in vitro fertilization treatment underwent neuropsychological testing before, during, and after treatment with leuprolide acetate and gonadotrophins. The neuropsychological test battery was selected on the basis of previous patients' symptomatic complaints during periods of hypoestrogenism with leuprolide acetate.

RESULTS

Depending upon the tests administered, some individuals showed significant cognitive deficits during therapy particularly in the areas of memory, fine motor coordination, and two-point discrimination. Two of the 18 subjects showed very substantial neuropsychological sequelae including memory gaps and disturbances in a variety of neuropsychological test performances. However, in terms of group statistics, only two-point discrimination and delayed recall memory test performance proved significant. Not all measures were sensitive for the group, as many tests displayed a balance between individuals who showed practice effects and those who showed detrimental effects.

CONCLUSIONS

For a substantial portion of individuals, hypoestrogenism can result in statistically significant or clinically noteworthy problems with memory, dexterity, and two-point discrimination.

Neuropsychiatric correlates of theta bursts in patients with closed head injury

Twenty-five head-injured patients with localized theta bursts on standard or 24 h ambulatory EEG were administered a standardized interview for neuropsychiatric symptoms associated with complex partial seizures (e.g. olfactory hallucinations, memory gaps) and a battery of neuropsychological tests. Although the formal neuropsychological test performances of these patients were relatively normal they reported an abundance of seizure-like behavioural symptoms. While the frequency of these symptoms was high, they did not occur in a stereotyped complex or sequence. These findings suggest that localized theta bursts may be diagnostic of an underlying neuroelectrical disorder.

The phenomenology of multiple partial seizure-like symptoms without stereotyped spells: an epilepsy spectrum disorder?

Consistent with previous reports by neuropsychiatrists, the results of the present investigation confirmed the existence of a neurobehavioral disorder characterized by the subjective experiencing of multiple cognitive, affective, and psychosensory phenomena similar to those associated with more classic partial seizure disorders. According to the literature, such patients typically respond favorably to anticonvulsants although they lack the customary motor manifestations of complex partial seizure (CPS) disorders and typically do not have stereotyped spells. This neuropsychiatric syndrome has recently been termed epilepsy spectrum disorder (ESD). In the present study, 30 patients with ESD were matched with equal numbers of treatment-refractory CPS patients and normal controls. All subjects were administered a standardized interview consisting of 35 cognitive, affective, and psychosensory partial seizure-like symptoms. The results indicated that ESD patients endorsed significantly more partial seizure-like symptoms than did CPS patients and controls. Relatively low levels of symptom endorsement by an unmatched psychiatric comparison sample indicated that the high levels of symptom endorsement by ESD patients could not be attributed to the presence of psychiatric dysfunction per se. Analysis of responding to 'foil' items unrelated to partial seizures indicated that high levels of symptom endorsement by ESD patients did not merely reflect a deviant response. Although ESD patients seldom present themselves at tertiary care epilepsy centers, the study of such patients is likely to be of relevance to mainstream epileptology.

Dichotic listening failure in dysphoric neuropsychiatric patients who endorse multiple seizure-like symptoms

In the present investigation, the dichotic word listening performance of a sample of 25 dysphoric neuropsychiatric patients who endorsed multiple partial seizure-like symptoms was compared with that of matched samples of normal controls and patients with mood disorders who did not endorse multiple seizure-like symptoms. Eighty percent of the patients who endorsed multiple episodic phenomena failed the dichotic listening task, compared with 8% of normal controls and 28% of patients with typical mood disorders. After treatment with carbamazepine, a subsample of polysymptomatic patients manifested significantly fewer seizure-like symptoms. This clinical improvement was typically associated with markedly improved dichotic listening performance in most cases. The results are consistent with our previous hypothesis that "subclinical" electrophysiological dysfunction may severely disrupt the normal transmission and processing of auditory information. Because it is sensitive to this type of presumed cerebral dysfunction and relatively specific, impaired dichotic listening performance is likely to be a useful clinical marker for this complex neuropsychiatric syndrome.

Dichotic listening and complex partial seizures

This study reports on 24 patients with multiple symptoms of untreated complex partial seizures (CPSz) who performed poorly at baseline assessment on a brief dichotic word listening task and subsequently improved following successful anticonvulsant therapy directed at treating seizure symptoms. These preliminary findings suggest that, in the absence of macroscopic structural lesions, dynamic electrophysiological dysfunction may interfere with the processing and transmission of simultaneously presented auditory information.

Tinker toy test performance and vocational outcome in patients with closed-head injuries

Fifty patients who had suffered closed-head injury with no resultant physical disabilities and 25 normal controls were administered a modified version of Lezak's Tinker Toy Test. All head-injured patients were examined at least 24 months following medical clearance to return to work. Twenty-five of the head injured had been unable to return to work or sustain normal competitive employment as a result of their head injuries. The remaining 25 had returned to their previous jobs successfully or had been employed for at least 6 months prior to assessment. Whereas all but one of the head injured who returned to work scored normally on the Tinker Toy Test, nearly half of the nonreturnees performed below the level of the worst control.

The role of individual difference in determining the nature of comprehension defects in aphasia

This study was concerned with the relationship between locus of lesion and subtypes of language comprehension defect in aphasia. Previous studies had indicated that performance in sound recognition identified two subtypes of aural comprehension deficit and that performance in pantomime recognition identified two subtypes of reading comprehension defect. Defects in sound recognition and pantomime recognition were found in association with a variety of lesion loci. However, comprehension defective aphasics with normal sound recognition or pantomime recognition had lesions closely similar in location and size to those of aphasics who performed poorly on these tests. Findings suggest that whether an aphasic with a language comprehension defect is impaired in sound recognition or pantomime recognition depends, at least in part, on individually variable predisposing factors. It would appear possible that this phenomenon reflects a separate dimension of hemispheric cerebral dominance.

Prognostic significance of anosmia in patients with closed-head trauma

Among 40 patients who developed total anosmia as a result of closed-head injury, virtually all had major vocational problems during the two or more years after being medically cleared to return to work. None had major motor or sensory deficits, and the majority had above average intelligence and memory. However, most demonstrated psychosocial deficits of a type typically associated with damage to orbital frontal cortex. Vocational outcome for patients with partial anosmia was more variable with only about half having manifest vocational problems.

Locus of lesion in impaired pantomime recognition

This study was concerned with the relationship between intrahemispheric locus of lesion and defective pantomime recognition in a population of left hemisphere damaged aphasics. Defects in pantomime recognition appeared to result from lesions in basal ganglia and areas 40, 39, 37 and 22. At the same time, however, a significant minority of aphasics with lesions in these various loci did not show defects in pantomime recognition.

CT scan correlates of sound recognition defect in aphasia

This study was concerned with the relationship between defects in sound recognition and intrahemispheric locus of lesion. Previous studies have shown that defects in sound recognition are common in association with left hemisphere lesions resulting in aphasias with comprehension deficits and are uncommon in association with other unilateral lesions. Current findings indicate that defects in sound recognition, occurring within the first month post onset of aphasia, may be associated with lesions of basal ganglia, the auditory cortex (both primary and association cortices), supramarginal gyrus, angular gyrus, and area 37. At the same time, however, a number of patients with lesions in these areas failed to show sound recognition defects.

Ideogram reading in normal and dyslexic children

This study was concerned with the ideogram reading performances of groups of reading disabled and normal children. While adults with acquired alexia have associated defects in ideogram reading, all of the dyslexic children performed at normal adult levels. It was found that ideogram reading in control children is rather slow to develop, with only 7 and 8 year old subjects performing like normal adults; this is in contrast to other reading-related cognitive tasks in which normal performance develops earlier.

Color association performances of dyslexic and normal children

The performances of normal and dyslexic children were evaluated on a test of nonverbal color association. All performances by developmental dyslexics were well within normal limits. In addition, all normal children age 6 and above performed at normal adult levels in color association.

Alexia for ideograms: implications for kanji alexia

This study was concerned with a model for kanji reading applicable in a non-Japanese population of aphasics. The experimental task required aphasic subjects to match animals with their footprints, a type of ideogram "reading" requiring no special training. As is true for kanji, footprint reading defects were consistently associated with word reading impairment, but some aphasics with defects in word reading performed normally in footprint reading. All with defects in footprint reading were also impaired in letter recognition or pantomime recognition. One aphasic's pattern of symptoms was quite similar to the rare phenomenon of Gogi aphasia. Implications for kanji alexia are discussed.

Reversible steroid dementia in patients without steroid psychosis

Six patients developed dementia-like cognitive changes that appeared to result from administration of steroid medications. Four of the patients never showed symptoms of steroid psychosis; the remaining two continued to show steroid dementia well after their steroid psychoses had resolved. The dementia was characterized by deficits in memory retention, attention, concentration, mental speed and efficiency, and occupational performance. All six patients eventually recovered normal mental status following discontinuation or reduction of steroid medications. Larger prospective studies are needed to determine the prevalence and nature of the syndrome.

The prognostic significance of sound recognition in receptive aphasia

Among 42 aphasics with notable to severe aural verbal comprehension defects in the acute stage of aphasia, 20 with normal sound recognition showed rapid and almost complete recovery of aural comprehension, regardless of how severely aural comprehension was initially impaired. Among 22 receptive aphasics with impaired sound recognition in the acute stage of aphasia, only 32% recovered rapidly; 45% had impairment two years after onset. Results indicated that intact sound recognition predicts rapid and complete recovery of aural comprehension.

Phonemic imperception in aphasia

This study investigated characteristics of 14 aphasics with impaired phoneme discrimination identified from a population of 100 patients with left hemisphere lesions. All patients with impaired phoneme discrimination were significantly impaired in aural comprehension, but many showed intact sound recognition and some showed normal reading comprehension. Defects in phoneme discrimination were typically seen in the acute stage of aphasia resulting from stroke; and in most instances, defects in phoneme discrimination were no longer apparent 4 months postonset. All patients who recovered normal phoneme discrimination also made significant improvement in aural comprehension. The findings support the concept that some aural comprehension defects result from a specific disturbance in phoneme discrimination.

Gerstmann syndrome without aphasia: a longitudinal study

A case of "pure" and complete Gerstmann syndrome resulting from a focal vascular lesion in the posterior parietal area of the left hemisphere and not associated with aphasic disorder or general mental impairment is described. The initial symptom presentation of this patient supported the concept of the autonomous nature of the Gerstmann aggregate but longitudinal findings suggested that these symptoms did not in fact represent a coherent syndrome.

Color "amnesia" without aphasia

Following an apparent left parietal CVA, a patient developed a severe and nearly complete color amnesia which was not associated with any disturbance in color vision or color perception. Like all previously reported cases with color amnesia, this patient was alexic but, unlike most previously reported cases, he was not aphasic.

Colour association and "colour amnesia" in aphasia

"Colour association" performance of 50 aphasic patients was investigated by means of a test in which they identified the characteristic colours of objects shown in line drawings. All aphasics with defects in colour association were impaired in reading comprehension. However, some (33%) retained normal aural comprehension. Approximately half the aphasics with receptive language impairment performed normally in colour association. The findings suggest that "colour amnesia" may be the result of a specific cognitive disturbance which is also responsible for a subtype of aphasic alexia.

Qualitative aspects of pantomime recognition defect in aphasia

This study investigated the performance pattern of aphasic patients on a pantomime recognition test in which one of the four response alternatives was an object semantically related to the correct choice. Aphasics with defective pantomime recognition made 71% of their total errors on the semantic foils, and for the majority of such patients, semantic errors represented 80 to 100% of total errors. Only aphasics with objective evidence of confusion failed to make highly frequent semantic errors. The findings suggest that most aphasics who fail pantomime recognition are impaired because of semantically vague understanding of the pantomimes' intended meaning rather than complete lack of understanding of the pantomime.

Sound recognition in relation to aural language comprehension in aphasic patients

This study was undertaken to determine whether some aphasic defects in aural language comprehension might be a reflection of cognitive impairment which also affects the recognition of meaningful, non-verbal sounds. Defects in sound recognition were consistently associated with aural comprehension defects of at least comparable severity and the majority of aphasics with impaired aural comprehension failed sound recognition. Although some aphasics with impaired aural comprehension performed normally in sound recognition, their language comprehension impairments were not of lesser severity than those shown by aphasics failing sound recognition. The relationship between sound recognition and reading comprehension was different in nature from that between sound recognition and aural comprehension.

Linguistic correlates of pantomime recognition in aphasic patients

Aphasic patients were given tests assessing pantomime recognition, reading comprehension, aural comprehension, and naming ability to determine whether defective pantomime recognition could be the result of a disturbance of symbolic thinking also affecting linguistic functioning. Defects in pantomime recognition always occurred in conjunction with reading defects of at least comparable severity, but reading defects sometimes occurred without comparable defects in pantomime recognition. The relationship of pantomime recognition with both aural comprehension and naming ability was significantly weaker than that between pantomime recognition and reading comprehension. The implications of the findings with regard to other nonverbal aphasic symptoms and the role of sensory modality factors are discussed.

Visuospatial judgment. A clinical test

We constructed and developed a brief test assessing capacity for discriminating the direction of lines. Application of the test to patients with unilateral brain disease disclosed a remarkably high frequency of defective performance in those with right hemisphere lesions. The performance of patients with left hemisphere lesions was comparable to that of control patients. Brevity and ease of administration make the test convenient for clinical use.

Visual localization in patients with unilateral brain disease

The accuracy of localization of briefly exposed single dots and pairs of dots was assessed in patients with lesions of the left and right hemispheres and in control patients without history or evidence of brain disease. A remarkably high frequency of impaired performance was found in the patients with right hemisphere lesions. The performance of the patients with left hemisphere lesions was comparable with that of the control patients. Visual field defect was associated with defective localization in the right hemisphere group but not in the left hemisphere group. Aphasic disorder and age were not related to performance level. The relationship of the findings to those of previous studies of visual localization in patients with unilateral brain disease is discussed.