Hippocampal - diencephalic - cingulate networks for memory and emotion: An anatomical guide

This review brings together current knowledge from tract tracing studies to update and reconsider those limbic connections initially highlighted by Papez for their presumed role in emotion. These connections link hippocampal and parahippocampal regions with the mammillary bodies, the anterior thalamic nuclei, and the cingulate gyrus, all structures now strongly implicated in memory functions. An additional goal of this review is to describe the routes taken by the various connections within this network. The original descriptions of these limbic connections saw their interconnecting pathways forming a serial circuit that began and finished in the hippocampal formation. It is now clear that with the exception of the mammillary bodies, these various sites are multiply interconnected with each other, including many reciprocal connections. In addition, these same connections are topographically organised, creating further subsystems. This complex pattern of connectivity helps explain the difficulty of interpreting the functional outcome of damage to any individual site within the network. For these same reasons, Papez’s initial concept of a loop beginning and ending in the hippocampal formation needs to be seen as a much more complex system of hippocampal–diencephalic–cingulate connections. The functions of these multiple interactions might be better viewed as principally providing efferent information from the posterior medial temporal lobe. Both a subcortical diencephalic route (via the fornix) and a cortical cingulate route (via retrosplenial cortex) can be distinguished. These routes provide indirect pathways for hippocampal interactions with prefrontal cortex, with the preponderance of both sets of connections arising from the more posterior hippocampal regions. These multi-stage connections complement the direct hippocampal projections to prefrontal cortex, which principally arise from the anterior hippocampus, thereby creating longitudinal functional differences along the anterior–posterior plane of the hippocampus

Biocontrol Potential of Forest Tree Endophytes

Peer reviewe

Is the meiofauna a good indicator for climate change and anthropogenic impacts?

Our planet is changing, and one of the most pressing challenges facing the scientific community revolves around understanding how ecological communities respond to global changes. From coastal to deep-sea ecosystems, ecologists are exploring new areas of research to find model organisms that help predict the future of life on our planet. Among the different categories of organisms, meiofauna offer several advantages for the study of marine benthic ecosystems. This paper reviews the advances in the study of meiofauna with regard to climate change and anthropogenic impacts. Four taxonomic groups are valuable for predicting global changes: foraminifers (especially calcareous forms), nematodes, copepods and ostracods. Environmental variables are fundamental in the interpretation of meiofaunal patterns and multistressor experiments are more informative than single stressor ones, revealing complex ecological and biological interactions. Global change has a general negative effect on meiofauna, with important consequences on benthic food webs. However, some meiofaunal species can be favoured by the extreme conditions induced by global change, as they can exhibit remarkable physiological adaptations. This review highlights the need to incorporate studies on taxonomy, genetics and function of meiofaunal taxa into global change impact research

Intrapopulation heterogeneity in floral nectar attributes and foraging insects of an ecotonal Mediterranean species

A population of Buglossoides purpurocaerulea (L.) I.M. Johnst. (Boraginaceae–Lithospermeae) located in Lecceto (Siena Province, Tuscany, central Italy) has been studied to compare floral nectar attributes and forager species between sun-exposed and shaded plants. Flower anthesis and maturity of sexual organs were also investigated. Average flower anthesis lasted 3–4 days. Stigma receptivity and anther dehiscence occurred on the first day. Nectar production also began on the first day and maximum production occurred on second-third day. Significantly greater volumes and total sugars were recorded in individuals exposed to the sun. Nectar HPLC analysis showed a similar hexose-dominant sugar profile for all the individuals with percentages of sucrose, glucose and fructose around 5, 48 and 47 %, respectively. Protein amino acids represent the 90 % of the overall free amino acids profile. Significant differences between relative percentages of serine and proline were found between sun-exposed and shaded individuals. Empis pennipes and Bombilyus major were the most frequent insect visitors to shaded and sun-exposed individuals, respectively. The hexose dominance of the nectar of B. purpurocaerulea, an exception among the Mediterranean Lithospermeae, may be related to the habitat where this plant generally grows, i.e. the forest-edge, and to pollination mainly performed by dipterans