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1.  TOP-DOWN CONTROL OF VISUAL ATTENTION 
Current opinion in neurobiology  2010;20(2):183-190.
Summary
Top-down visual attention improves perception of selected stimuli and that improvement is reflected in the neural activity at many stages throughout the visual system. Recent studies of top-down attention have elaborated on the signatures of its effects within visual cortex and have begun identifying its causal basis. Evidence from these studies suggests that the correlates of spatial attention exhibited by neurons within the visual system originate from a distributed network of structures involved in the programming of saccadic eye movements. We summarize this evidence and discuss its relationship to the neural mechanisms of spatial working memory.
doi:10.1016/j.conb.2010.02.003
PMCID: PMC2901796  PMID: 20303256
2.  Mechanisms of sleep-dependent consolidation of cortical plasticity 
Neuron  2009;61(3):454-466.
Summary
Sleep is thought to consolidate changes in synaptic strength, but the underlying mechanisms are unknown. We investigated the cellular events involved in this process in ocular dominance plasticity (ODP) - a canonical form of in vivo cortical plasticity triggered by monocular deprivation (MD) and consolidated by sleep via undetermined, activity-dependent mechanisms. We find that sleep consolidates ODP primarily by strengthening cortical responses to non-deprived eye stimulation. Consolidation is inhibited by reversible, intracortical antagonism of NMDA receptors (NMDARs) or cAMP-dependent protein kinase (PKA) during post-MD sleep. Consolidation is also associated with sleep-dependent increases in the activity of remodeling neurons, and in the phosphorylation of proteins required for potentiation of glutamatergic synapses. These findings demonstrate that synaptic strengthening via NMDAR and PKA activity is a key step in sleep-dependent consolidation of ODP.
doi:10.1016/j.neuron.2009.01.007
PMCID: PMC2665998  PMID: 19217381
V1; AP; NREM; REM; ODP; OD; MD; EEG; EMG; LTD; LTP; NMDAR; AVP; VEH; CBI; NBI; MI; SI; DE; NDE; ERI; VR; PKA; cAMP; CREB; Rp-8-Cl-cAMPS; AMPAR; GluR1; CaMKII; ERK
3.  Mid-fusiform Activation during Object Discrimination Reflects the Process of Differentiating Structural Descriptions 
Journal of cognitive neuroscience  2008;20(9):1711-1726.
The present study explored constraints on mid-fusiform activation during object discrimination. In three experiments, participants performed a matching task on simple line configurations, nameable objects, three dimensional (3-D) shapes, and colors. Significant bilateral mid-fusiform activation emerged when participants matched objects and 3-D shapes, as compared to when they matched two-dimensional (2-D) line configurations and colors, indicating that the mid-fusiform is engaged more strongly for processing structural descriptions (e.g., comparing 3-D volumetric shape) than perceptual descriptions (e.g., comparing 2-D or color information). In two of the experiments, the same mid-fusiform regions were also modulated by the degree of structural similarity between stimuli, implicating a role for the mid-fusiform in fine differentiation of similar visual object representations. Importantly, however, this process of fine differentiation occurred at the level of structural, but not perceptual, descriptions. Moreover, mid-fusiform activity was more robust when participants matched shape compared to color information using the identical stimuli, indicating that activity in the mid-fusiform gyrus is not driven by specific stimulus properties, but rather by the process of distinguishing stimuli based on shape information. Taken together, these findings further clarify the nature of object processing in the mid-fusiform gyrus. This region is engaged specifically in structural differentiation, a critical component process of object recognition and categorization.
doi:10.1162/jocn.2008.20116
PMCID: PMC2675283  PMID: 18345986

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