Interference Produces Different Forgetting Rates for Implicit and Explicit Knowledge

Abstract

Abstract. Exposure to a repeating set of target strings generated by an artificial grammar in a speeded matching task generates both explicit and implicit knowledge. Previous research has shown that implicit knowledge (assessed via a priming measure) is preserved after a retention interval of one week but explicit knowledge (assessed via recognition) is significantly reduced ( Tunney, 2003 ). In two experiments, we replicated and extended Tunney's findings. Experiment 1 was a partial replication of the experiment conducted by Tunney (2003) , and demonstrated that the decline in recognition shown by Tunney was not due to a repetition of test items at the pre and post times of assessment. In addition, Experiment 1 lends credibility to Tunney's assumption that recognition scores assess explicit rather than implicit knowledge. Experiment 2 extended Tunney's findings theoretically by demonstrating that interference can produce the pattern of findings demonstrated in the present Experiment 1 as well as in Tunney (2003) .

Temporal Stability of Implicit Sequence Knowledge

“…Thus, the implicit knowledge measure was not affected by the retention interval. This particular finding replicates the findings of previous experiments with artificial grammars (Tamayo & Frensch, 2007; Tunney, 2003). Despite the fact that RTs decreased for both new and old items as a consequence of practice during T1, the RT savings of old over new items were preserved…”

“…Previous research on the implicit learning of artificial grammars has shown that implicit and explicit knowledge may exhibit different forgetting trajectories (Tamayo & Frensch, 2007; Tunney, 2003; Tunney & Bezzina, 2007). In this context, implicit knowledge is normally assessed by priming, that is, the facilitation expressed in reaction time-savings that participants reveal when they produce sequences generated by the underlying artificial grammar.…”

“… Previous research has shown that explicit and implicit knowledge of artificial grammars may decay at different rates (e.g., Tamayo & Frensch, 2007; Tunney, 2003). We extend these findings to sequential regularities embedded in serial reaction time (SRT) tasks.…”

Position–item associations play a role in the acquisition of order knowledge in an implicit serial reaction time task.

“…Perlman and Tzelgov (2009, Experiment 1), for instance, also used short spatial sequences (4 or 5 in length), which were clearly separated for the participants by intervening irrelevant trials. Tunney (2003; see also, e.g., Perlman & Tzelgov, 2009; Stadler, 1989; Tamayo & Frensch, 2007; Ziessler, 1998) provided one instance where start cues have also been used in a choice reaction task with a regular sequence. There, the words “START” and “END” had been inserted between sequences generated by an artificial grammar.…”

Offline Improvement in Learning to Read a Novel Orthography Depends on Direct Letter Instruction

“…It is speculated that, in the current study, learning in the Word‐Alph and Word‐Arb groups may have suffered greater interference from general everyday activities of university students such as reading and attending classes, because they require item‐specific declarative learning. Studies using artificial grammar and paired associates paradigms show greater effects of retroactive interference in declarative compared with nondeclarative learning (Graf & Schacter, 1987; Tamayo & Frensch, 2007; Tunney, 2003). Finally, even if Offline improvement cannot be considered an exclusive marker of procedural learning, given the greater susceptibility of declarative learning to rapid decay and interference, procedural consolidation is more likely to manifest in Offline improvement and may thus explain the results of the current study.…”