It has recently been demonstrated that a lateralized distractor that matches the individual's top-down control settings elicits an N2pc wave, an electrophysiological index of the focus of visual-spatial attention, indicating that contingent capture has a visual-spatial locus. Here, we investigated whether contingent capture required capacity-limited central resources by incorporating a continge...

It is widely acknowledged that visual input is processed along two anatomically and functionally distinct pathways--a ventral pathway for conscious perception and a dorsal pathway for action control. The present study investigated whether the apparent direct and unmediated processing in the dorsal stream is subject to capacity limitations. Specifically, we tested whether a simple dorsal task of...

to study the critical period of weeds competition with sugar beet and determine the duration that the crop can tolerate the weeds, a field experiment was carried out at esfahan agicultural research center, in kabotarabad-esfahan during 1999-2000.  the experiment conducted in rcb design with 14 treatments and four replications. the treatments included control throughout the growth season (as a c...

Evidence suggests that there is a critical, or at least a sensitive, period for language acquisition, which ends around puberty. The existence of this period is explained by an evolutionary model which assumes that (a) linguistic ability is in principle (if not in practice) measurable, and (b) the amount of language controlled by an individual conferred selective advantage on it. In this model,...

BACKGROUND Providing specialised services to individuals experiencing first-episode psychosis (FEP) is a relatively new endeavour. AIMS To overview developing services for newly diagnosed cases of FEP and the context in which they develop. METHOD This paper describes five model multi-element FEP programmes, outlines recent evaluation studies of FEP services, discusses current evidence gaps ...

Synapse elimination is considered to be the final step in neural circuit formation, by causing refinement of redundant connections formed at earlier developmental stages. The developmental loss of climbing fiber innervation from cerebellar Purkinje cells is an example of such synapse elimination. It has been suggested that NMDA receptors are involved in the elimination of climbing fiber synapse...

The ultimate attainment level of Second Language Acquisition (L2A) contrasts sharply with that of First Language Acquisition (L1A) (Birdsong, 1999, p.1). That is: various success versus universal success (Gleitman & Newport, 1995, p.1). This significant difference between L1A and L2A is explained by the Critical Period Hypothesis (CPH). The CPH states that for language acquisition, either first...

In previous studies we found that there is a critical period during rat postnatal development when motor training starting at age 30 days (P30) but not before or after this age, induces a bilateral lifetime drop in Bmax of the muscarinic radioligand [3H]QNB in striatum. We examined the possibility that striatal NGF level would be a determining factor for the normal occurrence of this synaptic p...