the existence of a wse generally implies that there is some type of access or encoding advantage that words have in the mind that pseudowords or single letters do not have. various studies have proposed that the distinction is a result of pronounceability differences (nonwords are not pronounceable and therefore are not as easily remembered), frequency (real words are more frequently encountered and used), meaningfulness (real words have semantic value and therefore are better retained in memory), orthographic regularity (real words follow familiar spelling conventions and are therefore better retained in memory), or neighborhood density (real words tend to share more letters with other words than nonwords and therefore have more activation in the mind).