This is a particularly serious complication for neuroscientists

to consider going forward because the highest levels of 5hmC are found in the brain and its exact function is still unclear (Globisch et al., 2010). Fortunately, new methods of detection have been published in the past few months that will slowly begin to be incorporated into the already complicated toolbox for epigenetic detection. The findings of Uchida and colleagues (2011) further suggest the intriguing possibility that GDNF serum levels may be predictive of an individual’s coping ability. Interestingly, GDNF serum levels are reported to be lower in patients with major depression and bipolar disorder (Takebayashi et al., 2006), and a positive response to electroconvulsive therapy in patients with pharmacologic-resistant depression Bcl 2 inhibitor has been associated with Paclitaxel concentration increased GDNF serum levels (Zhang et al., 2009). Perhaps individuals with a family history of depression may someday

benefit from a test of their stress-induced GDNF response and subsequent pharmacologic intervention. “
“The cerebral cortex of mammals and in particular of primates is organized into a large number of functionally specialized areas that need to cooperate in a context- and goal-directed way in order to support cognitive and executive functions. Meta-analyses of anatomically identified cortico-cortical connections as well as investigations of effective connectivity with multisite recordings of electrical activity or functional magnetic resonance imaging (fMRI) indicate that the cortical connectome has small-world properties. Small-world network architectures assure that all nodes in the network

can communicate with each other via pathways with minimal length and minimal number of intervening nodes (for review see Sporns and Koetter, 2004). Nothing, however, comes without price. In such a highly connected all system, the flow of signals has to be constrained and coordinated in a task-dependent way. Thus, from instance to instance communication among the nodes of the network needs to be gated in order to allow for the selection of relevant sensory information and the configuration of functional networks that are optimally adapted to the respective behavioral goal. This requires dynamic control of information flow on timescales of tens to a few hundreds of milliseconds within the dense network of fixed anatomical connections. As a consequence the efficiency of the connections needs to be continuously adjusted. There are numerous options to dynamically modify the gain of neuronal connections: both the efficiency of synapses and the responsivity of postsynaptic neurons can be changed by multiple mechanisms that operate at various timescales and in a use-dependent manner. In addition, there are computational strategies to effectively gate communication among neurons.