For several years the frontal lobes, known to play a role in higher-order cognitive functioning, have been thought to contribute to episodic memory (EM) – a contribution in which researchers have recently made efforts to delineate. Here I will evaluate the notion that frontal lobes contribute to EM, and suggest reasons as to how it might do this.
Lesion studies
We can look at lesion studies to assess the contribution of the frontal lobes to EM. Unlike cued-recall and recognition tasks (which offer cues to motivate retrieval), free-recall tasks require participants to recruit tactical processing to search for memory items (Moscovitch, 1992). Research has shown that frontal lobe damage may impair initiation of such processes. Recall on words …show more content…
fMRI research has shown that prefrontal activation during encoding is predictive of later recognition memory. Specifically, both Rugg et al., (1999) and Kirshoff et al., (2000) found increased activation in the inferior frontal gyrus (i.e., ventrolateral PFC) for both words and scenes, respectively, that were subsequently remembered. One explanation of this effect might be that these areas facilitate ‘working memory’ processes which work to improve memory encoding (Aguirre et al., 1997), yet another explanation is that these areas are sensitive to the novelty/familiarity of the item (Knight & Nakada, 1998) which can be useful in making recognition judgements (Yonelinas et al., 1998) – a possibility which has received plentiful support. Although it might not be completely obvious as to how ventrolateral PFC regions may contribute to encoding, the same regions were found to be activated during memory retrieval, (Ranganath et al., 2000). Furthermore, in the same study the right middle frontal gyrus (i.e., dorsolateral PFC) was activated in both encoding and retrieval tasks, suggesting that these regions are responsible for cognitive processes useful for both memory encoding and retrieval. Thus, when looking at the broad array of available data, we might conclude that the prefrontal cortex might not be necessary for EM, but rather it implements complex cognitive processes that fasciliate memory encoding and subsequent
Lesion studies
We can look at lesion studies to assess the contribution of the frontal lobes to EM. Unlike cued-recall and recognition tasks (which offer cues to motivate retrieval), free-recall tasks require participants to recruit tactical processing to search for memory items (Moscovitch, 1992). Research has shown that frontal lobe damage may impair initiation of such processes. Recall on words …show more content…
fMRI research has shown that prefrontal activation during encoding is predictive of later recognition memory. Specifically, both Rugg et al., (1999) and Kirshoff et al., (2000) found increased activation in the inferior frontal gyrus (i.e., ventrolateral PFC) for both words and scenes, respectively, that were subsequently remembered. One explanation of this effect might be that these areas facilitate ‘working memory’ processes which work to improve memory encoding (Aguirre et al., 1997), yet another explanation is that these areas are sensitive to the novelty/familiarity of the item (Knight & Nakada, 1998) which can be useful in making recognition judgements (Yonelinas et al., 1998) – a possibility which has received plentiful support. Although it might not be completely obvious as to how ventrolateral PFC regions may contribute to encoding, the same regions were found to be activated during memory retrieval, (Ranganath et al., 2000). Furthermore, in the same study the right middle frontal gyrus (i.e., dorsolateral PFC) was activated in both encoding and retrieval tasks, suggesting that these regions are responsible for cognitive processes useful for both memory encoding and retrieval. Thus, when looking at the broad array of available data, we might conclude that the prefrontal cortex might not be necessary for EM, but rather it implements complex cognitive processes that fasciliate memory encoding and subsequent