Verbal learning in frontal patients: area 9 is critical for employing semantic strategies.

INTRODUCTION: Learning is a long-term memory process heavily influenced by the control processes implemented by working memory, including recognition of semantic properties of items by which subjects generate a semantic structure of engrams. AIM: The aim of this study is to investigate the verbal learning strategies of patients affected by a tumor in the left frontal lobe to highlight the role of area 9. METHOD: Ten patients with frontal low-grade gliomas and ten healthy control subjects, matched for age, sex and education, were recruited and then evaluated with a two-part verbal learning test: multi-trial word list learning in free recall, and multi-trial word list learning preceded by an explicit semantic strategy cue. Frontal patients were divided into two groups: those either with frontal lesions involving or sparing area 9. RESULTS: In comparison to healthy control subjects, frontal patients with lesions involving area 9 memorized fewer words and displayed difficulty in using semantic strategies. When the strategy was suggested by the examiner, their performance improved, but to a lesser extent than the healthy control. Conversely, frontal patients with lesions sparing area 9 showed similar results to healthy control subjects. CONCLUSION: The results suggested that, while the identification of the categorical criterion requires the integrity of the entire dorsolateral prefrontal area, only area 9, and not the surrounding areas, could be responsible for the effective use of semantic strategies in learning tasks.

Mild brain injury and anticoagulants: Less is enough.

BACKGROUND: Despite the higher theoretical risk of traumatic intracranial hemorrhage (ICH) in anticoagulated patients with mild head injury, the value of sequential head CT scans to identify bleeding remains controversial. This study evaluated the utility of 2 sequential CT scans at a 48-hour interval (CT1 and CT2) in patients with mild head trauma (Glasgow Coma Scale 13-15) taking oral anticoagulants. METHODS: We retrospectively evaluated the clinical records of all patients on chronic anticoagulation treatment admitted to the emergency department for mild head injury. RESULTS: A total of 344 patients were included, and 337 (97.9%) had a negative CT1. CT2 was performed on 284 of the 337 patients with a negative CT1 and was positive in 4 patients (1.4%), but none of the patients developed concomitant neurologic worsening or required neurosurgery. CONCLUSIONS: Systematic routine use of a second CT scan in mild head trauma in patients taking anticoagulants is expensive and clinically unnecessary.

Revised and extended norms for a picture naming test sensitive to category dissociations.

This study presents revised and extended norms for a picture naming test [Laiacona et al. (Arch Neurol Psicol Psichiatr 54:209-248, 1993)], based on 80 Snodgrass and Vanderwart (J Exp Psychol Human Learn Mem 6:174-215, 1980) pictures, devised to detect a categorical dissociation in the naming of items between biological and man-made categories. This survey is based on data from 215 healthy Italian participants. Since males are more frequently reported to have a disproportionate impairment of biological categories, norms have also been separately calculated for males and females and for the two categories of man-made objects and biological entities. Besides providing new normative values based on the Equivalent Scores approach, this study reappraises the interaction between categorical dissociations and sex in the normal population, and discusses some methodological aspects concerning the use of statistical norms.

Language disturbances associated to insular and entorhinal damage: study of a patient affected by herpetic encephalitis.

The herpes simplex encephalitis (HSE) patient reported in this study presented a left hemisphere lesion limited to the left insula and to the left anterior parahippocampal region. The patient was followed longitudinally, focusing on the aphasia type, the language recovery, and the integrity of semantic representations. The language deficit was of fluent type, without phonological impairment, and showed a good but incomplete recovery after four months. A semantic impairment was possible at the onset, but recovered quickly and did not present a disproportionate impairment of living categories.

Patients with primary cervical dystonia have evidence of discrete deficits in praxis.

BACKGROUND: Functional imaging and electrophysiological data from patients with primary dystonia reveal widespread abnormalities in brain areas associated with higher motor functions but to date there has been little investigation of the functional consequences of these abnormalities. The aim of this study was to use a battery of tests of praxis, based on those tests used in routine clinical examination, to uncover evidence of higher motor dysfunction in patients with primary cervical dystonia. METHODS: Praxis was assessed in 13 patients with primary cervical dystonia without hand involvement and in 29 age and sex matched controls. A semiquantitative praxis assessment was used which combined timed tests of meaningful and meaningless movements with copying of transitive and intratransitive hand movements and pantomime of tool use. Control tasks consisted of evaluation of motor speed, strength and a number of additional cognitive tasks. RESULTS: Patients made significantly more errors in copying meaningless gestures and were slow in the performance of meaningless sequences of hand movements. Copying meaningful gestures and performance of meaningful sequences of hand movements were normal. CONCLUSION: This study has identified a discrete deficit in praxis in dystonia patients and suggests additional functional consequences from the widespread pathophysiological abnormalities seen in primary dystonia.