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The ventromedial prefrontal cortex (vmPFC) and insular cortex are implicated in distributed neural circuitry that supports emotional decision-making. Previous studies of patients with vmPFC lesions have focused primarily on decision-making under uncertainty, when outcome probabilities are ambiguous (e.g. the Iowa Gambling Task). It remains unclear whether vmPFC is also necessary for decision-making under risk, when outcome probabilities are explicit. It is not known whether the effect of insular damage is analogous to the effect of vmPFC damage, or whether these regions contribute differentially to choice behaviour. Four groups of participants were compared on the Cambridge Gamble Task, a well-characterized measure of risky decision-making where outcome probabilities are presented explicitly, thus minimizing additional learning and working memory demands. Patients with focal, stable lesions to the vmPFC (n = 20) and the insular cortex (n = 13) were compared against healthy subjects (n = 41) and a group of lesion controls (n = 12) with damage predominantly affecting the dorsal and lateral frontal cortex. The vmPFC and insular cortex patients showed selective and distinctive disruptions of betting behaviour. VmPFC damage was associated with increased betting regardless of the odds of winning, consistent with a role of vmPFC in biasing healthy individuals towards conservative options under risk. In contrast, patients with insular cortex lesions failed to adjust their bets by the odds of winning, consistent with a role of the insular cortex in signalling the probability of aversive outcomes. The insular group attained a lower point score on the task and experienced more "bankruptcies". There were no group differences in probability judgement. These data confirm the necessary role of the vmPFC and insular regions in decision-making under risk. Poor decision-making in clinical populations can arise via multiple routes, with functionally dissociable effects of vmPFC and insular cortex damage. (Contains 6 figures and 2 tables.)

The neural correlates of naming concrete entities such as tools (with nouns) and naming actions (with verbs) are partially distinct: the former are linked to the left inferotemporal (IT) region, whereas the latter are linked to the left frontal opercular (FO) and left posterior middle temporal (MT) regions. This raises an intriguing question: How would such neural patterns be influenced by noun-verb homonymy, specifically, naming tasks in which the target words denote objects or actions (e.g., ''comb'')? To explore this, we conducted a PET study in which 10 normal participants named visually presented tools or actions. The factor of homonymy yielded interesting effects: For tools, non-homonymous nouns (e.g., ''camera'') activated left IT, whereas homonymous nouns (e.g., ''comb'') activated both left IT and left FO. For actions, non-homonymous (e.g., ''juggle'') and homonymous (e.g., ''comb'') verbs activated left FO, MT, and IT, but there was evidence that the FO and MT activations were less widespread for the homonymous verbs. We also found that retrieval of the same exact words (e.g., ''comb'' and ''comb'') produced differential activation in left MT-there was greater MT activation when the words were being used to name actions, than when they were being used to name tools. Our results suggest that noun-verb homonymy has an important influence on the patterns of neural activation associated with words denoting objects and actions, and that even when the phonological forms are identical, the patterns of neural activation are different according to the demands of the task.

Using both the lesion method and functional imaging (positron emission tomography) in large cohorts of subjects investigated with the same experimental tasks, we tested the following hypotheses: (A) that the retrieval of words which denote concrete entities belonging to distinct conceptual categories depends upon partially segregated regions in higher-order cortices of the left temporal lobe; and (B) that the retrieval of conceptual knowledge pertaining to the same concrete entities also depends on partially segregated regions; however, those regions will be different from those postulated in hypothesis A, and located predominantly in the right hemisphere (the second hypothesis tested only with the lesion method). The analyses provide support for hypothesis A in that several regions outside the classical Broca and Wernicke language areas are involved in name retrieval of concrete entities, and that there is a partial segregation in the temporal lobe with respect to the conceptual category to which the entities belong, and partial support for hypothesis B in that retrieval of conceptual knowledge is partially segregated from name retrieval in the lesion study. Those regions identified here are seen as parts of flexible, multi-component systems serving concept and word retrieval for concrete entities belonging to different conceptual categories. By comparing different approaches the article also addresses a number of method issues that have surfaced in recent studies in this field.

A study of patients with preferential amygdala lesions reveals that bilateral damage to human amygdala impairs specific recognition of facial expressions. Human amygdala is crucial for recognition of fear in facial expressions and recognition of multiple emotions in a single facial expression. However, recognition of personal identity from faces does not involve amygdala.

Pick's disease is often thought of as being a degenerative disease involving the frontal lobes of the brain, and indeed it is often a dementing illness characterized by frontal lobe signs. Yet, even the first case described by Pick himself involved the left temporal lobe and was characterized by aphasia (impaired speech). The authors present the case of a 59-year-old physician with deteriorating ability to use words, although his speech was fluent and his comprehension appeared to be intact. Death resulting from pneumonia provided an opportunity for autopsy and the confirmation of Pick's disease. At the time of his initial presentation, the patient reported noticing a decline in his ability to choose the proper word over a three-year period. Six months later, he retired from his practice because of his difficulty naming things, but there was no sign of deterioration of his other skills. In fact, his skill at performing surgical procedures was intact at the time of retirement. After retirement he played tennis with his friends with no signs of loss of skill, and managed his investment portfolio without error. The patient developed psychiatric problems after a car accident, which occurred about two years after his initial presentation, and he died of pneumonia four months later. Gross examination of the patient's brain revealed the presence of atrophy, which was more pronounced on the left than the right hemisphere. Neurofibrillary tangles, which are common in Alzheimer's disease and other brain diseases, were not seen. Neuritic plaques, a characteristic feature of Alzheimer's disease, were not present. However, Pick's bodies (round structures visible in the cytoplasm of affected neurons) were identified, confirming that this case was indeed Pick's disease. The authors suggest that in cases of aphasia, particularly when anomia (the inability to name objects) is the primary symptom, Pick's disease be considered as a possible diagnosis. (Consumer Summary produced by Reliance Medical Information, Inc.)

Lis Valley Irrigation District located in the coastal center of Portugal is administered by a users' association which manages the operation and maintenance of the main pumping and water conveyance infrastructures to the plots. As part of a project supported by the agricultural European Innovation Partnership, a study carried out in collaboration with farmers and focusing on the performance of the collective supply network has identified priority courses of action for achieving water savings by reconciling rural development with environmental and economic sustainability.

Le périmètre irrigué de la Vale do Lis situé dans le centre côtier du Portugal est administré par une association d’usagers qui gère l’exploitation et l’entretien des principales infrastructures de pompage et d’adduction de l’eau vers les parcelles. Dans le cadre d’un projet soutenu par le partenariat européen d'innovation agricole, une étude menée en collaboration avec les agriculteurs et focalisée sur les performances du réseau d’approvisionnement collectif a permis d’identifier les pistes d’actions prioritaires pour réaliser des économies d’eau en conciliant développement rural et durabilité environnementale et économique.

Like all parts of the body, the human brain shows the effects of age. Autopsy and in vivo neuroimaging studies have shown that aging affects different parts and tissues of the brain at different rates, and that there may be sexual dimorphism in the rates Of brain aging. We report on a study of age effects on the gray-white volumes of the major lobes and gyri of the human cerebrum. Regions of interest were defined by identifying neuro-anatomical surface landmarks on 3D reconstructions of T1-weighted contiguous coronal sections through the whole brain (1.5-1.6mm slices, 110-120 per brain). The following regions were manually traced in each hemisphere: frontal, temporal, parietal, and occipital lobes; cingulate gyrus; insula (see Allen et al. 2002, AJPA 118:341-358). Subjects included 44 women (23-74 years) and 43 men (22-88 years). All were right-handed, healthy, and without neurological or psychiatric disease. As expected, the cerebral hemispheres decrease in size with age, with the white matter decreasing at a faster rate than the gray matter. The cerebrum atrophies more quickly in men compared to women: older women had about 5% less GM and 8% less WM than younger women; older men had about 8% less GM and 15% less WM than younger men. There is also variation by anatomical region in the loss of tissue with age. These results have implications for understanding the aging process in general, and for testing evolutionary hypotheses associated with human aging that have a cognitive component. Funding: NIH 1P50DC03189-01A1 and the Mathers Foundation.