Gyula Demeter

etrieval practice of Rp+ items and forgetting is the consequence of these inhibitory processes
that acts to resolve competition between target items during retrieval. It is also assumed that
this inhibition reflects executive control mechanism (Storm, 2011).
The above findings on the other hand can be explained by interference mechanism (e.g.,
Camp, Pecher, & Schmidt, 2007). For example in the retrieval practice paradigm we can say
that forgetting is caused by interference mechanism because the cue (e.g., vegetables)
becomes stronger for the practiced item (e.g., carrot), while the associations between the cue
and non-practiced items (e.g., cabbage) become weaker. According to this approach the
emphasis is on the modified effectiveness of the cue to retrieve specific targets.
To distinguish between these two approaches the final memory test should use
independent cues, cues which are not associated with the practiced items. This seems a
reasonable criteria because Anderson (2003) states that the item itself is inhibited and not the
relation between the target and its category. There are studies with evidence supporting the
RIF effect by independent cues (e.g., Johnson & Anderson, 2004; Anderson, Green, &
McCulloch, 2000; Anderson & Spellman, 1995) and studies which failed to replicate the
reported findings (e.g., Camp et al., 2007).
Another question refers to the duration of the RIF effect, and it has been found that it
disappears after 24 hours (delayed testing) if the retrieval-practice phase followed
immediately the encoding phase (MacLeod & Macrea, 2001), suggesting that it reflects a
reversible change in state. Most of researchers consider the retrieval practice effect a short
rather then a long term effect (Anderson, 2001; Saunders & MacLeod, 2002). Our study
found evidence supporting the presence of this effect after 12 hours, if a nocturnal sleep
occurred during the retention intervals (Racsmány, Conway & Demeter, 2010). According to
the episodic inhibition account in the retrieval practice procedure the study phase gives rise to
the formation of an episodic memory and the practice phase establishes a pattern of activation
and inhibition over these contents. Then, during recall, this pattern of activation-inhibition
will mediate the access to memories (Racsmány & Conway, 2006).
There were studies on RIF with different clinical populations (schizophrenia, Alzheimer
disease, depression, brain damage) but as far as it is known, there are no studies involving
OCD patients. It is important to consider that the study of OCD in this context can be with
critical relevance in this area because it can produce relevant results considering the debate
between the inhibitory and interference accounts, to the relation between executive functions
and RIF and to the possible modulator effect of stress on RIF.
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