Attention to object categories: Selection history determines the breadth of attentional tuning during real-world object search.

People excel at learning the statistics of their environments. For instance, people rapidly learn to pay attention to locations that frequently contain visual search targets. Here, we investigated how frequently finding specific objects as search targets influences attentional selection during real-world object search. We investigated how learning that a specific object (e.g., a coat) is task-relevant affects searching for that object and whether a previously frequent target would influence search more broadly for all items of that target's category (e.g., all coats). Across five experiments, one or more objects from a single category were likely targets during a training phase, after which objects from many categories became equally likely to be targets in a neutral testing phase. Participants learned to find a single frequent target object faster than other objects (Experiment 1, N = 44). This learning was specific to that object, with no advantage in finding a novel category-matched object (Experiment 2, N = 32). In contrast, learning to prioritize multiple exemplars from one category spread to untrained objects from the same category, and this spread was comparable whether participants learned to find two, four, or six exemplars (Experiment 3, N = 72). These differences in the breadth of attention were due to variability in the learning environment and not differences in task (Experiment 4, N = 24). Finally, a set-size manipulation showed that learning affects attentional guidance itself, not only postselective processing (Experiment 5, N = 96). These experiments demonstrate that the breadth of attentional tuning is flexibly adjusted based on recent experience to effectively address task demands. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Noonan syndrome patient-specific induced cardiomyocyte model carrying SOS1 gene variant c.1654A>G.

Noonan syndrome (NS) is a dominant autosomal genetic disorder, associated with mutations in several genes that exhibit multisystem abnormal development including cardiac defects. NS associated with the Son of Sevenless homolog 1 (SOS1) gene mutation attributes to the development of cardiomyopathy and congenital heart defects. Since the treatment option for NS is very limited, an in vitro disease model with SOS1 gene mutation would be beneficial for exploring therapeutic possibilities for NS. We reprogrammed cardiac fibroblasts obtained from a NS patient and normal control skin fibroblasts (C-SF) into induced pluripotent stem cells (iPSCs). We identified NS-iPSCs carry a heterozygous single nucleotide variation in the SOS1 gene at the c.1654A > G. Furthermore, the control and NS-iPSCs were differentiated into induced cardiomyocytes (iCMCs), and the electron microscopic analysis showed that the sarcomeres of the NS-iCMCs were highly disorganized. FACS analysis showed that 47.5% of the NS-iCMCs co-expressed GATA4 and cardiac troponin T proteins, and the mRNA expression levels of many cardiac related genes, studied by qRT-PCR array, were significantly reduced when compared to the control C-iCMCs. We report for the first time that NS-iPSCs carry a single nucleotide variation in the SOS1 gene at the c.1654A>G were showing significantly reduced cardiac genes and proteins expression as well as structurally and functionally compromised when compared to C-iCMCs. These iPSCs and iCMCs can be used as a modeling platform to unravel the pathologic mechanisms and also the development of novel drug for the cardiomyopathy in patients with NS.