Egocentric and allocentric navigation strategies in Williams syndrome and typical development

Abstract

Recent findings suggest that difficulties on small-scale visuospatial tasks documented in Williams syndrome (WS) also extend to large-scale space. In particular, individuals with WS often present with difficulties in allocentric spatial coding (encoding relationships between items within an environment or array). This study examined the effect of atypical spatial processing in WS on large-scale navigational strategies, using a novel 3D virtual environment. During navigation of recently learnt large-scale space, typically developing (TD) children predominantly rely on the use of a sequential egocentric strategy (recalling the sequence of left-right body turns throughout a route), but become more able to use an allocentric strategy between 5 and 10 years of age. The navigation strategies spontaneously employed by TD children between 5 and 10 years of age and individuals with WS were analysed. The ability to use an allocentric strategy on trials where spatial relational knowledge was required to find the shortest route was also examined. Results showed that, unlike TD children, during spontaneous navigation the WS group did not predominantly employ a sequential egocentric strategy. Instead, individuals with WS followed the path until the correct environmental landmarks were found, suggesting the use of a time-consuming and inefficient view-matching strategy for wayfinding. Individuals with WS also presented with deficits in allocentric spatial coding, demonstrated by difficulties in determining short-cuts when required and difficulties developing a mental representation of the environment layout. This was found even following extensive experience in an environment, suggesting that - unlike in typical development - experience cannot contribute to the development of spatial relational processing in WS. This atypical presentation of both egocentric and allocentric spatial encoding is discussed in relation to specific difficulties on small-scale spatial tasks and known atypical cortical development in WS.

The Davida Teller Award Lecture, 2016

“…Nardini, Atkinson, Braddick, & Burgess (2008) showed that WS children showed a poor and anomalous pattern in using different frames of reference to recall the location of a hidden object. Similar anomalies have been found in locating objects in larger-scale space (Mandolesi et al, 2009) and in the spatial reference frames and strategies used by WS children for navigation (e.g., Broadbent, Farran, & Tolmie, 2014; Farran, Formby, Daniyal, Holmes, & Van Herwegen, 2016). …”

Route‐learning strategies in typical and atypical development; eye tracking reveals atypical landmark selection in Williams syndrome

“…) and is useful for the development of configural knowledge (Broadbent et al . ). The current study did not require configural knowledge of the environment for successful task completion, and thus distant landmarks were relatively less useful than proximal landmarks.…”

“…, , ; Broadbent et al . ), as well as neural impairments in the hippocampus (Meyer‐Lindenberg et al . ), an area associated with navigation in typical adults (Burgess ).…”

Genetic contributions to visuospatial cognition in Williams syndrome: insights from two contrasting partial deletion patients

“…More recently, deficits in large-scale spatial navigation have also been identified in WS [22,23]. But which genes contribute to these small-scale and large-scale spatial impairments remains a topic of debate.…”