Aging effects on memory encoding in the frontal lobes.

Functional magnetic resonance imaging (fMRI) was used to compare frontal-lobe activation in younger and older adults during encoding of words into memory. Participants made semantic or nonsemantic judgements about words. Younger adults exhibited greater activation for semantic relative to nonsemantic judgements in several regions, with the largest activation in the left inferior frontal gyrus. Older adults exhibited greater activation for semantic judgments in the same regions, but the extent of activation was reduced in left prefrontal regions. In older adults, there was a significant association between behavioral tests of declarative and working memory and extent of frontal activation. These results suggest that age-associated decreases in memory ability may be due to decreased frontal-lobe contributions to the initial encoding of experience. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Learning in monkeys after combined lesions in frontal and anterior temporal lobes.

Assigned 19 rhesus monkeys to 2 unoperated control groups, a group sustaining prefrontal lobectomy, and a group with prefrontal lobectomy plus removal of the anterior temporal neocortex. Ss were compared on delayed response ability, as well as on the ability to make object discriminations and to form learning sets. The combined frontal-temporal lesion did not increase the delayed response deficit produced by frontal damage alone, but it significantly increased difficulty in making 2-object discriminations and apparently also depressed oddity discrimination performance. Ability to form learning sets was not impaired in either lesioned group. (15 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Toward a theory of episodic memory: The frontal lobes and autonoetic consciousness.

Adult humans are capable of remembering prior events by mentally traveling back in time to reexperience those events. In this review, the authors discuss this and other related capabilities. considering evidence from such diverse sources as brain imaging, neuropsychological experiments, clinical observations, and developmental psychology. The evidence supports a preliminary theory of episodic remembering, which holds that the prefrontal cortex plays a critical, supervisory role in empowering healthy adults with autonoetic consciousness—the capacity to mentally represent and become aware of subjective experiences in the past, present, and future. When a rememberer mentally travels back in subjective time to reexperience his or her personal past, the result is an act of retrieval from episodic memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Neuropsychological indexes of a partial frontal syndrome in patients with nonfrontal gliomas.

33 brain tumor patients (aged 26–74 yrs) were investigated with quantitative and qualitative neuropsychological assessments, systematic behavioral observations, and recordings of regional cerebral blood (rCBF). Ss with supratentorial highly malignant gliomas showed severe disturbances of attention, lack of control over premotor and executive functions, distractibility, a deficient abstract attitude, a loss of speech initiative, and diminished speech production. Such impairments are associated with functions of the frontal lobe system and may be related to frontal functional cortical changes as mirrored by rCBF. Signs of frontal dysfunction were seen in Ss with nonfrontal tumors and may suggest frontal lobe diaschisis in patients with Grade III–IV astrocytomas. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Let's inhibit our excitement: The relationships between Stroop, behavioral disinhibition, and the frontal lobes.

Objective: The Stroop (Stroop, 1935) is a frequently used neuropsychological test, with poor performance typically interpreted as indicative of disinhibition and frontal lobe damage. This study tested those interpretations by examining relationships between Stroop performance, behavioral disinhibition, and frontal lobe atrophy. Method: Participants were 112 patients with mild cognitive impairment or dementia, recruited through UCSF's Memory and Aging Center. Participants received comprehensive dementia evaluations including structural MRI, neuropsychological testing, and informant interviews. Freesurfer, a semiautomated parcellation program, was used to analyze 1.5T MRI scans. Behavioral disinhibition was measured using the Neuropsychiatric Inventory (Cummings, 1997; Cummings et al., 1994) Disinhibition Scale. The sample (n = 112) mean age was 65.40 (SD = 8.60) years, education was 16.64 (SD = 2.54) years, and Mini-Mental State Examination (MMSE; Folstein et al., 1975) was 26.63 (SD = 3.32). Hierarchical linear regressions were used for data analysis. Results: Controlling for age, MMSE, and color naming, Stroop performance was not significantly associated with disinhibition (β = 0.01, ΔR2 = 0.01, p = .29). Hierarchical regressions controlling for age, MMSE, color naming, intracranial volume, and temporal and parietal lobes, examined whether left or right hemisphere regions predict Stroop performance. Bilaterally, parietal lobe atrophy best predicted poorer Stroop (left: β = 0.0004, ΔR2 = 0.02, p = .002; right: β = 0.0004, ΔR2 = 0.02, p = .002). Of frontal regions, only dorsolateral prefrontal cortex atrophy predicted poorer Stroop (β = 0.001, ΔR2 = 0.01, p = .03); left and right anterior cingulate cortex atrophy predicted better Stroop (left: β = ?0.003, ΔR2 = 0.01, p = .02; right: β = ?0.004, ΔR2 = 0.01, p = .02). Conclusion: These findings suggest Stroop performance is a poor measure of behavioral disinhibition and frontal lobe atrophy even among a relatively high-risk population. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Role of the striatum, cerebellum, and frontal lobes in the learning of a visuomotor sequence

This study was designed to examine the role of the striatum, cerebellum, and frontal lobes in the implicit learning of a visuomotor sequence. The performance of patients with idiopathic Parkinson's disease (PD), with damage to the cerebellum, or with a circumscribed lesion to the frontal lobes was thus compared to that of separate groups of matched normal control subjects on an adapted version of the Repeated Sequence Test. This paradigm consists of a visual reaction-time task with a fixed embedded sequence of finger movements to be performed based on presentation of visual stimuli. Subjects received four blocks of trials (i.e., 40 presentations of a 10-item sequence) per day over 6 training days. Following the last experimental session, subjects were also given two tests measuring their declarative knowledge of the sequence. Only PD patients with a bilateral striatal-dysfunction or patients with lesions to the cerebellum failed to improve their performance in the last three training sessions, hence suggesting an impairment late in the acquisition process. Further analyses revealed that such impairment was mainly implicit in nature, and that it could not be ascribed to a general decline in cognitive functioning, to mood disturbances, or to the severity of the motor symptoms. By contrast, the level of declarative knowledge of the sequence did not differ between the three clinical groups and their respective groups of normal subjects. These findings suggest that, unlike declarative memory, the incremental acquisition of a new visuomotor skill depends upon the integrity of both the striatum and the cerebellum, but not of the frontal lobes.     

Neuropsychological studies of perception and visuomotor control

According to recent conceptualizations, there are two separate cortical visual systems--each with its own distinctive cortical and subcortical links--and these two systems respectively serve the functions of perception and of motor control. These ideas have been arrived at through a confluence of neuroanatomical, electrophysiological, behavioural, and neuropsychological research. It is proposed that this distinction between two broad purposes of vision and their neural bases can provide useful working procedures for analysing both: (i) the nature of visuomotor processing in the normal brain; and also (ii) the abnormal patterns of visual processing that are seen in certain neurological conditions.     

Relationship of the Halstead-Reitan Neuropsychological Battery to the Luria-Nebraska Neuropsychological Battery.

Compared the major 14 scores of the Halstead-Reitan Neuropsychological Test Battery with the 14 summary scale scores of the Luria-Nebraska battery to investigate whether the batteries could predict one another and their effectiveness in a sample of 48 brain-damaged and 60 normal patients (mean age of all Ss 39 yrs). Discriminant analysis found both batteries equally effective in identifying brain damage, with hit rates of over 85%. A high degree of relationship between the Luria-Nebraska scale scores and the selected 14 scores of the Halstead-Reitan was found. (12 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Role of the striatum, cerebellum and frontal lobes in the automatization of a repeated visuomotor sequence of movements

Recently, Doyon et al. [20] demonstrated that lesions to both the striatum and to the cerebellum in humans produce a similar deficit in the learning of a repeated visuomotor sequence, which occurs late in the acquisition process. We now report the results of two experiments that were designed to examine whether this impairment was due to a lack of automatization of the repeating sequence of finger movements by using a dual-task paradigm and by testing for long-term retention of this skill. In Experiment 1, the performance of groups of patients with Parkinson's disease, or with damage to the cerebellum or to the frontal lobes, was compared to that of matched control subjects on the Repeated Sequence Test (primary task) and the Brooks' Matrices Test (secondary task). These two tests were administered concomitantly in both early and late learning phases of the visuomotor sequence. Overall, the groups did not differ in their ability to execute the primary task. By contrast, in accordance with the predictions, patients in Stages 2-3 of Parkinson's disease or with a cerebellar lesion failed to reveal the expected increase in performance on the secondary task seen with learning, suggesting that the latter groups of patients did not have access to the same level of residual cognitive resources to complete the matrices compared to controls. In Experiment 2, the same groups of patients and control subjects were retested again 10-18 months later. They were given four blocks of 100 trials each of the repeating sequence task, followed by a questionnaire and a self-generation task that measured their declarative knowledge of that sequence. The results revealed a long-term retention impairment only in patients who changed from Stage I to Stage II of the disease (suggesting further striatal degeneration) during the one-year interval, or who had a cerebellar lesion. By contrast, performance of the three clinical groups did not differ from controls on declarative memory tests. These findings suggest that both the striatum and the cerebellum participate to the automatization process during the late (slow) learning stage of a sequence of finger movements and that these structures also play a role in the neuronal mechanism subserving long-term retention of such a motor sequence behavior.     

Neuropsychological interpretation of the WAIS.

Discusses the use of the Wechsler Adult Intelligence Scale (WAIS) to detect brain damage. Patterns produced by types of damage that have been recognized in relation to WAIS subtests include chronic lateralized damage, acute lateralized damage, and slowly progressive diffuse damage. It is concluded that the WAIS is a valuable instrument for assessing brain damage when it is used in conjunction with other tests of brain damage. However, the WAIS is not a good diagnostic tool for determining either the existence of damage or laterality when it is used by itself. Most brain damaged patterns that are found on the WAIS can be produced by several types of other conditions, both functional and organic. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Cognitive resources and dual-task interference effects at retrieval in normal people: The role of the frontal lobes and medial temporal cortex.

Conducted 3 experiments to examine the hypothesis that concurrent secondary tasks at retrieval will interfere more with long-term, episodic memory functions involving the frontal lobes than those involving the medial temporal lobes hippocampus (MTL/H). The rationale is that strategic retrieval processes mediated by the frontal lobes place greater demands on cognitive resources than do relatively automatic associative retrieval processes (ecphory) mediated by the temporal lobes. In Exps 1 and 2, sequential finger tapping was performed at encoding, at retrieval, at both, or at neither. Recall of a categorized list of 16 words from the California Verbal Learning Test in Exp 1, and release from proactive inhibition (PI) in Exp 2, both being tests that involve the frontal lobes, were impaired if normal Ss tapped at both encoding and retrieval. Concurrent tapping had little effect on rate of learning in Exp 1 and on total words recalled during the buildup of PI in Exp 2, both of which are indices that are affected more by MTL/H than by frontal lesions. In Exp 3, tapping by normal Ss affected letter fluency, a test more sensitive to frontal lobe than temporal lobe damage, but not category fluency, for which the reverse is true. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The functional neuroanatomy of episodic memory: the role of the frontal lobes, the hippocampal formation, and other areas

Because it allows direct mapping of synaptic activity during behavior in the normal subject, functional neuroimaging with the activation paradigm, especially positron emission tomography, has recently provided insight into our understanding of the functional neuroanatomy of episodic memory over and above established knowledge from lesional neuropsychology. The most striking application relates to the ability to distinguish the structures implicated in the encoding and the retrieval of episodic information, as these processes are extremely difficult to differentiate with behavioral tasks, either in healthy subjects or in brain-damaged patients. Regarding encoding and retrieval, the results from most studies converge on the involvement of the prefrontal cortex in these processes, with a hemispheric encoding/retrieval asymmetry (HERA) such that the left side is preferentially involved in encoding, and the right in retrieval. However, there are still some questions, for instance, about bilateral activation during retrieval and a possible specialization within the prefrontal cortex. More expected from human and monkey lesional data, the hippocampal formation appears to play a role in both the encoding and the retrieval of episodic information, but the exact conditions which determine hippocampal activation and its fine-grained functional neuroanatomy have yet to be fully elucidated. Other structures are activated during episodic memory tasks, with asymmetric activation that fits the HERA model, such as preferentially left-sided activation of the association temporal and posterior cingulate areas in encoding tasks and preferentially right-sided activation of the association parietal cortex, cerebellum, and posterior cingulate in retrieval tasks. However, this hemispheric asymmetry appears to depend to some extent on the material used. These new data enhance our capacity to comprehend episodic memory deficits in neuropsychology, as well as the neural mechanisms underlying the age-related changes in episodic memory performances.     

Decreased energy demanding processes in the frontal lobes of schizophrenics due to neuroleptics? A 31P-magneto-resonance spectroscopic study

In the present investigation on 31P-magneto-resonance spectroscopic parameters in the frontal lobe, we found phosphocreatine levels and the ratio phosphocreatine/adenosine triphosphate to be increased (12.62 +/- 1.98% resp. 0.31 +/- 0.06) in 50 neuroleptic-treated schizophrenics, whereas no differences were detected in 10 neuroleptic-free patients (11.66 +/- 2.57% resp. 0.29 +/- 0.08) compared to 36 controls (11.37 +/- 1.45 resp. 0.29 +/- 0.04). This result points to a major role of neuroleptics in the metabolism of high-energy phosphates.     

Validity of the Luria-Nebraska Neuropsychological Battery.

D. Delis and E. Kaplan (see record 1983-24742-001) criticized the Luria-Nebraska Neuropsychological Battery for not meeting some assumptions of content validity and, by inference, construct validity. Delis and Kaplan also criticized C. J. Golden for advocating improper use of the test battery as a substitute for clinical training and knowledge. The present authors evaluate the major points of Delis and Kaplan, indicating which are cogent to the battery and which are based on misunderstandings of the manner in which the battery should be used. The theoretical structure of the scales of the battery is briefly described, as are approaches to interpretation. Studies indicating that the battery has validity as a neuropsychological test and the requirements needed for accurate application of the battery are examined. (13 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Neuropsychological problem-solving skills in the elderly.

This article describes the performance of a representative sample of 110 participants aged from 65 to 75 years. Participants completed the Trail-Making Test, Tactual Performance Test, and Booklet Category Test. Results confirmed that previously established cutoff scores used to determine impairment are not appropriate for this age group. Significant sex differences were found for the Tactual Performance Test and Booklet Category Test. Mean scores presented in this article provide useful normative standards for the three aforementioned tasks when given to patients aged from 65 to 75 years. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A cross-validation of the Luria-Nebraska Neuropsychological Battery.

30 brain-damaged males with evidence of unilateral left-hemisphere (mean age 58 yrs), unilateral right-hemisphere (mean age 57 yrs), or bilateral-diffuse brain lesions (mean age 41 yrs), as well as 10 normal control Ss (mean age 54 yrs), were administered the standardized Luria-Nebraska test battery. Data demonstrate that the battery was effective in discriminating brain-damaged from normal control Ss. However, it was relatively ineffective in distinguishing the laterality of brain damage. (6 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Diagnostic validity of the Halstead-Reitan Neuropsychological Battery.

Conducted a validity study of the Halstead-Reitan Neuropsychological Battery which compared it with the more popular physical diagnostic techniques. Ss were 89 patients about whom empirical findings could be used as criteria for physical and neuropsychological measures. Results indicate that the neuropsychological procedure, considered as a screening device, surpassed all physical measures in all neuropathological categories. Use of physical measures in a negative sense to exclude possible neuropathological statements may provide spuriously low hit rates. Validity coefficients for the Battery in terms of lateralization and identification of process for different process classifications are presented. (30 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Neuropsychological impairment in pedophiles.

Compared 15 heterosexual, 14 homosexual, and 10 bisexual male pedophiles (mean age 39 yrs) to 14 nonviolent nonsex offenders (mean age 25 yrs), using the Halstead-Reitan Neuropsychological Test Battery, the Luria-Nebraska Neuropsychological Battery, the Wechsler Adult Intelligence Scale (WAIS), and computerized tomography scans. Ss were classified into their groups based on criminal history, a standard sex history assessment, and a phallometric test of erotic preference. Pedophiles tended to have lower IQs than controls and showed significantly more impairment on all measures. Left temporo-parietal pathology was noted more often for pedophiles. Findings suggest that neuropsychological examination can provide useful and potentially discriminating information in pedophilia and should be considered an important supplement in clinical assessments of the disorder. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Workshops in Neuropsychological Assessment.

A past issue of Professional Psychology (February 1982) dealt with peer review and quality assurance. These issues are of particular interest to clinical neuropsychology, as evidenced by several articles in Professional Psychology. Over the past 5 years, clinical neuropsychology has rapidly emerged as an important diagnostic and treatment specialty within psychology. Unfortunately, from the standpoint of peer review and quality assurance, this growth has not been appropriately governed. The intention of writing this letter is to bring attention to this particular problem. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Neuropsychological assessment of soccer players.

Assessed the attention and concentration of 31 soccer players (aged 18–24 yrs), who deliberately use the head to propel the ball, and 31 tennis players (aged 18–22 yrs). Ss were administered the Raven Progressive Matrices, Symbol Digit Modalities Test, Perceptual Speed Test, and Paced Auditory Serial Addition Test (PASAT). There were no significant differences between the 2 groups on these tests. However, there was a significant negative correlation between number of games played and performance on the PASAT. Also, a significantly greater number of soccer players reported experiencing headaches, dizziness, and passing out after a game. (PsycINFO Database Record (c) 2010 APA, all rights reserved)