The topic of this dissertation concerns the ways that (IN)ANIMACY distinctions interact with various sub-systems of the human language faculty, in particular, morpho-syntax. In Modern Standard Arabic (MSA), morpho-syntax and ANIMACY can be pit against each other directly on the same set of target words, allowing a close inspection of the time-course of the availability of different information in the integration of words into phrasal level structure. Although animate and inanimate singular nouns and plural animate nouns require matching GENDER and NUMBER agreement (e.g., on demonstratives, adjectives, finite verbs ... etc.), plural inanimate nouns trigger feminine singular agreement. This state of affairs presents the language comprehension mechanism with a conflict in which the ANIMACY properties of specific nouns render grammatical what would otherwise be a morpho-syntactic violation. Findings from two experiments (a web experiment and an ERP experiment) show that whereas singulars and animate plurals demonstrate uniform response accuracy and short latencies and replicate previous ERP findings (a LAN) from similar paradigms [Barber & Carreiras, 2003, 2005; Gunter et al., 2000)], our inanimate plurals (mismatch cases), show longer latency effects and a striking polarity reversal of a LAN-type response for the CORRECT but morpho-syntactically mismatched cases. To that end, I argue that during the early stages of parsing and sentence processing, morpho-syntax and conceptual/ lexical-semantic features are both available but completely independent and the locus of the interaction between morpho-syntactic and lexico-semantic features is post-lexical in the integration stage [in the sense of Friederici (2002)], where override processes are evoked and result in consequently licensing the mismatch cases and rendering them grammatical. If we understand ANIMACY as a conceptual semantic feature, this could be viewed as consistent with the "syntax first" accounts (Marslen-Wilson & Tyler, 1980; Frazier, 1987; Friederici, 1995, 2002; De Vincenzi, Job, Di Matteo, Angrilli, Penolazzi, Ciccarelli & Vespignani, 2003) in which syntax and conceptual semantics are argued to initially act independently; but also incorporates some aspects of the "interactive" accounts (MacDonald, Pearlmutter & Seidenberg, 1994) in arguing that both systems are available immediately. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://bibliotheek.ehb.be:2222/en-US/products/dissertations/individuals.shtml.]