Table 1.

Predictions and evidence for compensation by declarative memory in neurodevelopmental disorders.

Predictions			Evidence
	SLI	Dyslexia	Autism Spectrum Disorder	Tourette syndrome	OCD
Increased reliance (from either spontaneous learning or therapy) on strategies thought to depend on declarative memory	Chunking of complex linguistic forms (Oetting and Horohov, 1997; Thordardottir and Ellis Weismer, 2002; Ullman and Gopnik, 1999; Ullman and Pierpont, 2005; van der Lely and Ullman, 2001) Explicit rule memorization, including from instruction (Ullman and Gopnik, 1999; Ullman and Pierpont, 2005)	Memorization of whole word forms (chunking) (Bruck, 1990; Rack et al., 1992; Shaywitz et al., 2003; Snowling et al., 1994) Reading improves when supported by semantic context (Ben-Dror et al., 1991; Nation and Snowling, 1998). Reading improvements during development may be due to semantic knowledge (Chiarello et al, 2006; Shaywitz et al., 2003) Reliance of therapies on explicit rules (Alexander and Slinger-Constant, 2004; Ehri and Nunes, 2001)	Formulaic speech (chunked phrases and sentences) (Dobbinson et al., 2003; Tager-Flusberg and Calkins, 1990; Walenski et al., 2006) Explicit memorization of social scripts, rules and event schemas (Bishop and Norbury, 2002; Eales, 1993; Landa, 2000; Portman, 2006) Theory of mind learned explicitly (Frith, 2004; Klinger et al, 2007; Senju et al, 2009) Category learning based on explicit rules rather than implicit prototypes(Klinger and Dawson, 2001) Reliance of therapies on explicit rules, scripts and event schemas (Charlop-Christy and Kelso, 2003; Crozier and Tincani, 2007; Ganz et al, 2008; Ivey et al., 2004; Krantz and McClannahan, 1998)	Habit reversal therapy, which involves the explicit control of tics, is effective in TS (Frank and Cavanna, 2013; Himle et al., 2006)	Habit reversal therapy, as well as other cognitive behavioral therapies, are effective in OCD (March, 1995; Watson and Rees, 2008)
Increased reliance on the neural system underlying declarative memory	Electrophysiological evidence: N400 ERP components found for grammatical processing (Fonteneau and van der Lely, 2008; Neville et al., 1993; Ullman and Pierpont, 2005)	Functional and structural MRI evidence: Behavioral interventions lead to increased hippocampal activation and volumes (Eden et al., 2004; Gebauer et al., 2012; Krafnick et al., 2011; Temple et al., 2003) Electrophysiological evidence: N400 ERP components found for grammatical processing (Cantiani et al., 2012; Cantiani et al., 2013)	fMRI evidence: Increased activation in medial temporal lobe structures during some social processing tasks (Dichter et al., 2012; Vaidya et al., 2011)	TBD	fMRI and PET evidence: Increased activation in MTL structures (and decreased activation in the basal ganglia) during procedural memory and executive tasks (Rauch et al., 1997; Rauch et al., 2007; Rauch et al., 2001; Roth et al., 2003; van den Heuvel et al., 2005)
Indicators of better declarative memory are associated with better compensation	Better grammatical abilities in individuals with better declarative memory (Lum et al., 2012)	Better reading ability in individuals with better declarative memory and larger hippocampi/MTL structures (Hedenius et al., 2013; Krafnick et al., 2011)	TBD	TS symptoms better in individuals with larger hippocampi/MTL structures (Peterson et al., 2007; Plessen et al., 2009; Worbe et al, 2010)	OCD symptoms better in individuals with larger hippocampi/MTL structures (Carmona et al., 2007; Peterson et al., 2007; van den Heuvel et al., 2009)

Note. SLI: specific language impairment. TS: Tourette syndrome. OCD: obsessive-compulsive disorder. TBD: To be determined; we are not aware of any relevant studies. (f)MRI: (functional) magnetic resonance imaging. PET: positron emission tomography. ERP: event-related potential. MTL: medial temporal lobe.