This study aimed to reveal the relationship between language and thinking, more specifically the linguistic relativism theory as formulated by Levinson (1996) and colleagues (Pederson, Danziger et al., 1998). The authors examined developmental change in the use of frames of reference in five typically developing groups (3-10 years) and a Williams syndrome group (7-21 years). Williams syndrome children were chosen to tease apart the different effects of language (relatively unimpaired) and cognition (mildly/severly impaired). Participants had to memorize a spatial array, then turn 180° and choose between two arrays, differing only in their frame of reference (relative or absolute). The authors also administered various tests (TROG, RAVEN, Corsi, RMET) to examine individual differences. The developmental trend was exactly the opposite of the hypothesis posed by Levinson: speakers of an inherently intrinsic/relative language seemed to prefer absolute choices increasingly with age. Yet a connection between language and reference frames could not be established by way of a correlation between administered language proficiency tests and preferred frame of reference. Williams syndrome children showed radically different preferences in the test, so we must conclude that their relatively impaired language could not give them a crutch in the task. The authors conclude that probably there is a threefold causality in the choice of reference frame in children: 1. Biological effects (such as sex and handedness) and 2. individual differences (such as intelligence and spatial memory) have a large impact on spatial reference choices (possibly only in childhood). 3. Both immediate (visible allocentric and egocentric cues) and general environment (education, culture) are important, yet language alone does seem to play a role.