Neuropsychological studies of the frontal lobes.

Summarizes the current state of knowledge of prefrontal lobe functions as derived from studies and observations of adult humans following frontal lobe damage. Following an overview of the neuroanatomy and neuropathology, frontal lobe activities are presented under the following headings: motor functions; sensory, perception, and construction functions; attention; abnormal awareness; flexibility–perseveration; language; memory; cognition; personality; localization; and hemispheric activity. Six specific prefrontal functions are suggested as the principal disorders underlying many if not all of the described manifestations. Thus, prefrontal damage can (1) separate action from knowledge, (2) impair the ability to handle sequential behaviors, (3) impair the ability to establish or change a set, (4) impair the ability to maintain a set, (5) impair the ability to monitor personal behavior, and (6) produce attitudes of apathy. (5? p ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Inhibition of ongoing responses following frontal, nonfrontal, and basal ganglia lesions.

The authors investigated the role of the frontal lobes and the basal ganglia in the inhibition of ongoing responses. Seventeen patients with frontal lesions (FG), 20 patients with lesions outside the frontal cortex (NFG), 8 patients with lesions to the basal ganglia (BG), and 20 orthopedic controls (OG) performed the stop-signal task that allows the estimation of the time it takes to inhibit an ongoing reaction (stop signal reaction time [SSRT]). The FG and the BG showed significantly longer SSRTs than the OG. Within the FG, patients with right and bilateral lesions showed significantly longer SSRTs than patients with left lesions. Results provide evidence for a role of the frontal lobes and the basal ganglia in the inhibition of ongoing responses. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Neuropsychological deficits in patients with an anterior communicating artery syndrome: a multiple case study

The neuropsychological performance of five patients with an anterior communicating artery (ACoA) syndrome (amnesia, confabulation and personality changes) was studied. Neuroimaging techniques revealed a basal forebrain and frontal lobe pathology in all patients. The limbic system appeared intact. There was no evidence for an intellectual deterioration relative to the estimated premorbid IQ in four patients. Regarding attention, all patients showed significant deficits. Visuospatial disabilities could not be observed. On tests of executive functioning, all patients did exhibit severe problems. Every patient displayed a profound amnesic syndrome. A retrograde amnesia could be documented and was characterised by a temporal gradient. Short-term memory appeared normal. Concerning long-term memory, all patients scored out of the normal range on total immediate recall tasks. Four patients showed a normal recognition performance but produced a large number of false alarms. Despite a normal recognition performance, they were impaired in delayed recall tasks. However, one patient showed a full-blown amnesic syndrome, because his delayed recall and recognition of learned items were both depressed. Our results with regard to long-term memory functioning support the hypotheses which assume (1) the existence of recognition superiority and pathological false recognition, and (2) basal forebrain amnesia in ACoA patients.     

Neuropsychological functioning and determinants of morning alertness in patients with obstructive sleep apnea syndrome

Neuropsychological functioning is reported to be impaired in patients suffering from obstructive sleep apnea syndrome (OSAS). This syndrome is characterized by nocturnal respiratory disturbances, blood oxygen desaturations, sleep fragmentation, and excessive daytime sleepiness. Opinions are divided concerning the exact relationship between the observed cognitive deficits, nocturnal hypoxia, sleep disruption, and impaired daytime alertness. In the present study, morning neuropsychological function of 26 moderate to severe middle-aged sleep apneics is compared to that of 22 primary insomniacs. There were no performance differences on a range of neuropsychological tests among the two patient groups. In addition, the data suggest that morning alertness impairment, which is closely associated with a lack of slow wave sleep (SWS) and rapid eye movement (REM) sleep, is of major importance in inducing poorer cognitive performance in patients with moderate to severe sleep apnea.     

Dual-task performance in dysexecutive and nondysexecutive patients with a frontal lesion.

Patients with defined frontal lobe lesions were assigned to 1 of 2 groups based on whether they showed a behaviorally assessed dysexecutive syndrome or were behaviorally normal. All participants were tested on dual-task performance and on 2 tasks assumed to measure frontal lobe function, the Wisconsin Card Sorting Test and verbal fluency. The dysexecutive group differed significantly from the nondysexecutive in showing impaired capacity for dual-task coordination, but there were no significant differences on the Wisconsin Card Sorting Test and verbal fluency. Results are interpreted in terms of a multicomponent central executive, whose function is linked to, but not coterminous with, the operation of the frontal lobes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Neuropsychological correlates of decision making in patients with bulimia nervosa.

In addition to the core psychopathology of bulimia nervosa (BN), patients with BN often show impulsive behavior that has been related to decision making deficits in other patient groups, such as individuals with anorexia nervosa and pathological gamblers. However, it remains unclear whether BN patients also show difficulties in decision making. In this study, 14 patients with BN and 14 healthy comparison subjects, matched for age, gender, education, body mass index, and intelligence, were examined with the Game of Dice Task (M. Brand, E. Fujiwara, et al., 2005), a gambling task that has fixed winning probabilities and explicit rules for gains and losses, as well as with a neuropsychological test battery and personality questionnaires. On the task, the patients with BN chose the disadvantageous alternatives more frequently than did the comparison subjects. Performance on the Game of Dice Task was related to executive functioning but not to other neuropsychological functions, personality, or disease-specific variables in the BN group. Thus, in patients with BN, decision making abnormalities and executive reductions can be demonstrated and might be neuropsychological correlates of the patients' dysfunctional everyday-life decision making behavior. Neurocognitive functions should be considered in the treatment of BN. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Neuropsychological test feedback to patients with brain dysfunction.

The provision of neuropsychological test feedback is of central importance in helping patients and their families cope with the consequences of brain injury. A general framework for presenting feedback is described, with an emphasis on techniques designed to maximize patient benefit. Special issues involving test-related limitations, patient characteristics, and family involvement in the feedback process are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Neuropsychological outcome following anterior temporal lobectomy in patients with and without the syndrome of mesial temporal lobe epilepsy.

The nature, pattern, and degree of neuropsychological change following anterior temporal lobectomy (ATL) were examined as a function of the presence or absence of the syndrome of mesial temporal lobe epilepsy (MTLE). Fifty-four patients exhibited the syndrome of MTLE, while 34 patients were without the syndrome (non-MTLE). The test-retest performance of a group of 40 epilepsy patients who did not undergo surgery was used to derive regression based estimates of test-retest change. Overall, the MTLE group did not show significant cognitive decline following ATL. In contrast, the left non-MTLE group showed significant declines on verbal memory, confrontation naming, and verbal conceptual ability. Further, verbal memory was the most substantial area of decline, and was independent of seizure outcome. Clinical and theoretical implications of these findings are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Neuropsychological profiles in bipolar affective disorder and complex partial seizure disorder.

Compared neuropsychological profiles of bipolar patients, complex partial seizure disorder patients, and normal controls. Complex partial seizure patients performed worse than bipolar patients or normal controls in 1 of 5 neuropsychological domains examined in an ANOVA (focusing-execution) and on delayed verbal recall; they performed worse than bipolar patients in the verbal domain. Bipolar patients performed worse than normal controls in focusing-execution and showed clinical elevation on 1 scale of the MMPI. The data suggest both similarities and differences in the neuropsychological profiles of patients with bipolar affective disorder and patients with complex partial seizure disorder. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Imitative response tendencies in patients with frontal brain lesions.

It is widely accepted that patients with frontal lesions have problems inhibiting automatic response tendencies. Whereas inhibition deficits of overlearned responses have been extensively investigated using interference tasks like the Stroop task (J. R. Stroop, 1935), it is controversial whether patients with frontal brain lesions also have problems inhibiting imitative responses. Using an interference paradigm, the present study investigated imitative response tendencies in patients with frontal lesions. In addition, it tested whether patients deficient in the inhibition of imitative responses correspondingly have problems inhibiting overlearned responses. It was found that the group with frontal lesions displayed significantly stronger imitative response tendencies than the group with nonfrontal lesions. Furthermore, it was shown that the inhibition of imitative responses is functionally unrelated to Stroop interference. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Neuropsychological impairment in patients with schizophrenia and evidence of hyponatremia and polydipsia.

Patients with schizophrenia and water imbalance may represent a subset of patients with distinct pathophysiological abnormalities and susceptibility to cognitive impairment. Specifically, patients with polydipsia and hyponatremia have been shown to have smaller anterior hippocampal volumes, which are also associated with various impairments in neuroendocrine function. To determine whether abnormalities in patients with water imbalance extend to the cognitive realm, the present study evaluated neuropsychological functioning in three groups of patients with schizophrenia: polydipsic hyponatremic, polydipsic normonatremic, and nonpolydipsic normonatremic. Participants were administered cognitive tests assessing intelligence, attention, learning/memory (verbal, nonverbal, emotional), and facial discrimination. Hyponatremic patients showed poorer overall neuropsychological functioning relative to all other patients, and polydipsic normonatremic patients performed intermediate to the other two groups. Results indicate that patients with schizophrenia and polydipsia, and particularly those with hyponatremia, show prominent cognitive deficits relative to patients without water imbalance. The clinical, neuroendocrine, and cognitive abnormalities in these patients may arise from pathology within the anterior hippocampus and associated prefrontal/limbic brain regions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Letter and category fluency in patients with frontal lobe lesions.

This study examines the hypothesis that patients with frontal lobe lesions are impaired on tests of letter but not category fluency. This hypothesis was proposed by Moscovitch (1994), based on a series of cognitive studies with young, normal participants. A group of patients with lateral prefrontal lesions and age-matched controls were tested on 2 tests of verbal fluency, the FAS task and a category fluency task that used semantic categories as cues (e.g., animals). Patients with frontal lobe lesions generated fewer items than controls on both letter and category fluency. This effect did not interact with the type of fluency test, suggesting that the frontal lobes are more generally involved in verbal fluency. Moreover, this pattern of findings, along with previous results of impaired free recall and remote retrieval in this patient group, suggests that patients with frontal lobe lesions do not efficiently organize and develop retrieval strategies. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Ipsilateral motor activation in patients with cerebral gliomas

OBJECTIVE: The aim of this study is to provide neurophysiologic evidence of ipsilateral hemispheric activation in patients affected by intracerebral gliomas via the use of transcranial magnetic stimulation. BACKGROUND: The mechanisms involved in such ipsilateral activation have yet to be established, but they may involve preexisting routes that either are suppressed or undetected in the normal brain. Ipsilateral pathways may act in reserve, activated by the impairment of contralateral control. This hypothesis is suggested by the fact that the considerable size of the tumors in our patients is not matched by a proportionate loss of motor performance in the limbs contralateral to the affected hemisphere. However, it remains possible that ipsilateral motor-evoked potentials (iMEPs) may reflect reorganizational changes without significant functional effects. METHODS: The effects of such activation were investigated using both focal and nonfocal coils stimulating cortical motor areas, with MEPs recorded from both left and right thenar muscles. Fifteen healthy control subjects and seven patients were examined. RESULTS: iMEPs were generally absent in normal subjects, but in contrast they were obtained in the patients by stimulating the healthy hemisphere using both round and figure-of-eight coils. Distinct from contralateral MEPs, iMEPs are obtained with higher thresholds (range, 60 to 80% of stimulator output) and display longer latencies (20.9 msec versus 19.4 msec). CONCLUSIONS: Taken in conjunction with recent research using functional imaging brain exploration and a variety of clinical, anatomic, and neurophysiologic studies, our results reflect a growing awareness of ipsilateral motor control and its potential compensatory role when contralateral routes are damaged.     

Neuropsychological performance in Hallervorden-Spatz syndrome: A report of two cases.

Hallervorden-Spatz disease (HSD) is a rare progressive disorder characterized by iron deposition in the globus pallidus and zona reticularis of the substantia nigra. The cases of 2 Black female patients (aged 20–38 yrs) with diagnoses of probable HSD are evaluated, based on typical clinical course in conjunction with magnetic resonance imaging abnormalities restricted to the region of the globus pallidus. Ss' deficits included slowed cognitive processing speed, motor sequencing difficulty, constructional dyspraxia, and impaired recent memory functions. The constellation of behavioral deficits can be attributed to dysfunction of the frontal lobe, basal ganglia, or disruption of their functional interconnections. Additional deficits in language and visuospatial processing were also observed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Neuropsychological test performance in mildly hypoxemic patients with chronic obstructive pulmonary disease.

Previous research has demonstrated neuropsychological deficits in moderately to severely hypoxemic, chronic obstructive pulmonary disease (COPD) patients. The present article reports on the neuropsychological functioning of mildly hypoxemic COPD patients. 100 patients (mean age 61.5 yrs) and 25 controls (mean age 59.6 yrs) matched on relevant variables were given extensive neuropsychological tests including the WAIS, Wechsler Memory Scale, and Halstead-Reitan Neuropsychological Test Battery. Mild neuropsychological impairment was observed in the COPD Ss, with overall indexes of neuropsychological dysfunction correlating with resting partial pressure of oxygen. Depression and motivation to perform could not account for the results. Long-term reduced oxygen supply to the brain may account for these observed deficits. (24 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Neuropsychological function in young patients with unipolar major depression

BACKGROUND: While neuropsychological studies have consistently reported impaired cognition in elderly patients with unipolar depression, studies of cognitive function in younger patients with depression have produced equivocal results. The aim of this study was to examine the presence and nature of cognitive deficits in young patients with depression. METHODS: Neuropsychological function was assessed in 20 young patients with unipolar depression, in comparison to 20 age-, education- and IQ- matched controls. Subtests from the Cambridge Neuropsychological Test Automated Battery (CANTAB) were employed, as this battery has proved sensitive to deficits in middle-aged and elderly patients with depression. RESULTS: The patients were not impaired for short-term memory capacity, spatial working memory, planning ability, cognitive speed, delayed matching to sample or recognition memory. Compared to controls, the patients showed impaired subsequent movement latencies on the Tower of London task, suggesting deficits in the ability to sustain motor responses in depression. The depression group were also impaired on the task of attentional set shifting, requiring more trials to criterion at the intradimensional stage of the task and being more likely to fail the task at the extradimensional shift stage than controls. Further analysis indicated that half of the depression group failed to complete all stages of the set shifting task. These patients were more likely to have required in-patient hospitalization at some time during their illness. CONCLUSIONS: These results indicate that there are specific cognitive deficits in young patients with depression and that their presence may be related to a history of hospitalization.     

Recency discrimination deficits in frontal lobe patients.

Damage to the frontal lobes appears to cause a deficit in the temporal organization of memory. M. P. McAndrews and B. Milner (see record 1992-16996-001) found that S-performed tasks (SPTs), which involve the performance of actions with common objects, allowed frontal-lobe-damaged patients to circumvent this deficit and perform normally on recency judgments. The present investigation of the critical properties of SPTs compared the performance of frontal-lobe-damaged patients and healthy controls on recency judgments under 5 encoding conditions: SPT, naming, visual imagery, experimenter-performed tasks, and verbal elaboration. Patients' performance varied across encoding conditions, but controls' did not. Post hoc comparisons confirmed that patients performed significantly worse than controls across all encoding tasks except SPT. The findings help elucidate the nature of both SPTs and memory for temporal order. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Impaired retrieval from remote memory in patients with frontal lobe damage.

Patients with unilateral dorsolateral frontal lobe lesions and matched controls were given 2 tests of remote memory for public information, the Public Events Test and the Famous Faces Test. On both tests, the patients with frontal lobe lesions exhibited impaired recall for remote information. Recognition memory was relatively preserved. Provision of semantic and phonemic cues in the Famous Faces Test did not completely compensate for their recall deficit. These findings suggest that the remote memory impairment exhibited by frontal patients may be related to deficits in strategic search of memory. These deficits in retrieval from remote memory extend the array of memory deficits associated with damage to the frontal lobes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Evidence for intact semantic representations in patients with frontal lobe lesions.

Patients with frontal lobe lesions and control participants were assessed on 2 tests of semantic knowledge. In the triadic comparison task, participants were shown all possible triplets of 12 animal names and judged which 2 of each triplet were most alike. In the ordered similarity task, participants rank ordered animals in terms of their similarity to a target animal. For both tasks, semantic structure-- derived from multidimensional scaling techniques-- revealed similar representations in patients with frontal lobe lesions and control participants. Additional pathfinder analyses also produced networks that did not differ between groups. These patients exhibited intact semantic knowledge despite deficits on tests of free recall and verbal fluency that involved the same semantic category and exemplars. Thus, intact representation of semantic knowledge in frontal patients stands in contrast to their marked deficits in strategic retrieval of semantic knowledge. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Neuropsychological comparison of alcohol-exposed children with or without physical features of fetal alcohol syndrome.

Fetal alcohol syndrome (FAS) is associated with behavioral and cognitive deficits. However, the majority of children born to alcohol-abusing women do not meet the formal criteria for FAS and it is not known if the cognitive abilities of these children differ from those of children with FAS. Using a set of neuropsychological tests, 3 groups were compared: (a) children with FAS, (b) children without FAS who were born to alcohol-abusing women (the PEA group), and (c) normal controls. The results indicated that, relative to controls, both the FAS and the PEA groups were impaired on tests of language, verbal learning and memory, academic skills, fine-motor speed, and visual-motor integration. These data suggest that heavy prenatal alcohol exposure is related to a consistent pattern of neuropsychological deficits and the degree of these deficits may be independent of the presence of physical features associated with FAS. (PsycINFO Database Record (c) 2010 APA, all rights reserved)