Assessment of abstract behavior in a non-Western culture.

The question was raised whether tests of abstract ability were valid for cross-cultural comparisons. The first group of Ss consisted of 27 boys, about 15 years of age, from the Accra urban area, all of whom received the Goldstein-Scheerer Cube Test. The second group consisted of 317 boys who received the Raven Progressive Matrices Test on three successive weeks. The third group consisted of 32 boys who took the Kohs Block Design Test, administered and scored according to McConnell. The results showed that the cube Test performance is affected by environmental influences, and that the Progressive Matrices is susceptible to practice effects. Paradoxically the third group did about as well as McConnell's Ss on the Kohs Blocks who were shown to perform at a level comparable to Wechsler's standardization group. It was concluded that tests of abstract ability are no more "culture-free" than tests of intelligence. 30 references. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Induction of hair growth in ear wounds by cultured dermal papilla cells

In the adult hair follicle the dermal papilla plays a crucial role in the dermal-epidermal interactions that control hair production and events of the growth cycle. It has previously been shown that cultured cells from rat vibrissa follicle dermal papillae can stimulate hair growth when implanted into amputated follicles. This study investigated the effects of implanting low-passage cultured papilla cells into small incisional wounds in the rat ear pinna. The groups of fibers that emerged from wound sites were much larger than local hairs, and often had vibrissa-type characteristics. Later-passage papilla cells or cultured skin fibroblasts failed to elicit the same response. Histology revealed that big follicles were formed when papilla cells were trapped between the cut edges of the epidermis. Abnormally large follicles were seen at wound sites many months post-operatively. Independent of epidermal influence, cultured papilla cells in the wound dermis formed rounded papilla-like aggregates that also persisted until biopsy. A previously described method of wrapping papilla cells in glabrous epidermis was less successful in percentage terms but resulted in the production of one very large vibrissa-type follicle and fiber. These results further illustrate that the inductive powers and developmental information retained by cultured dermal papilla cells parallel the properties of their embryonic precursors; the findings may have implications for human hair growth.