title: Differential Effects of Encoding Instructions on Brain Activity Patterns of Item and Associative Memory.
abstract: Evidence from neuroimaging studies suggests a critical role of hippocampus and inferior frontal gyrus (IFG) in associative relative to item encoding. Here, we investigated similarities and differences in functional brain correlates for associative and item memory as a function of encoding instruction. Participants received either incidental (animacy judgments) or intentional encoding instructions while fMRI was employed during the encoding of associations and items. In a subsequent recognition task, memory performance of participants receiving intentional encoding instructions was higher compared with those receiving incidental encoding instructions. Furthermore, participants remembered more items than associations, regardless of encoding instruction. Greater brain activation in the left anterior hippocampus was observed for intentionally compared with incidentally encoded associations, although activity in this region was not modulated by the type of instruction for encoded items. Furthermore, greater activity in the left anterior hippocampus and left IFG was observed during intentional associative compared with item encoding. The same regions were related to subsequent memory of intentionally encoded associations and were thus task relevant. Similarly, connectivity of the anterior hippocampus to the right superior temporal lobe and IFG was uniquely linked to subsequent memory of intentionally encoded associations. Our study demonstrates the differential involvement of anterior hippocampus in intentional relative to incidental associative encoding. This finding likely reflects that the intent to remember triggers a specific binding process accomplished by this region.
authors.affiliation: Otto Hahn Group on Associative Memory, Max Planck Institute for Human Development, Berlin, Germany.|Aging Research Center, Karolinska Institutet and Stockholm University, Stockholm, Sweden.
authors.forename: Nina
authors.initials: N
authors.lastname: Becker
authors.affiliation: Aging Research Center, Karolinska Institutet and Stockholm University, Stockholm, Sweden.
authors.forename: Grégoria
authors.initials: G
authors.lastname: Kalpouzos
authors.affiliation: Aging Research Center, Karolinska Institutet and Stockholm University, Stockholm, Sweden.
authors.forename: Jonas
authors.initials: J
authors.lastname: Persson
authors.affiliation: Aging Research Center, Karolinska Institutet and Stockholm University, Stockholm, Sweden.
authors.forename: Erika J
authors.initials: EJ
authors.lastname: Laukka
authors.affiliation: Otto Hahn Group on Associative Memory, Max Planck Institute for Human Development, Berlin, Germany.|Aging Research Center, Karolinska Institutet and Stockholm University, Stockholm, Sweden.
authors.forename: Yvonne
authors.initials: Y
authors.lastname: Brehmer
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D001244:Association; D001921:Brain / Q000000981:diagnostic imaging / Q000502:physiology*; D001931:Brain Mapping; D005260:Female; D006801:Humans; D007600:Judgment / Q000502:physiology; D008279:Magnetic Resonance Imaging; D008297:Male; D008568:Memory / Q000502:physiology*; D014796:Visual Perception / Q000502:physiology; D055815:Young Adult