The Effect of Unitizing Word Pairs on Recollection Versus Familiarity-Based Retrieval - Further Evidence From ERPs

Abstract

We investigated the contribution of familiarity and recollection to associative retrieval of word pairs depending on the extent to which the pairs have been unitized through task instructions in the encoding phase. Participants in the unitization condition encoded word pairs in the context of a definition that tied them together such that they were treated as a coherent new item, while in the control condition word pairs were inserted into a sentence frame in which each word remained an individual unit. Contrasting event-related potentials (ERERPs) elicited in a subsequent recognition test by old (intact) and recombined (a new combination of two words from different study pairs) word pairs, an early frontal effect, the putative ER P correlate of familiarity-based retrieval, was apparent in the unitization condition. The left parietal old/new effect, reflecting recollection-based retrieval, was elicited only in the control condition. This suggests that in the unitization condition only, familiarity was sufficiently diagnostic to distinguish old from recombined pairs, while in the control condition, recollection contributed to associative recognition. Our findings add to a body of literature suggesting that unitization of associations increases the relative contribution of familiarity to subsequent associative retrieval.

Unitization modulates recognition of within‐domain and cross‐domain associations: Evidence from event‐related potentials

“…Our first key finding was that associative recognition of compounds (but not of noncompounds) was associated with modulation of an early frontal effect—conventionally interpreted as the putative electrophysiological correlate of early retrieval processes such as familiarity—as indicated by decreased frontal negativity for old compared to rearranged compounds in the early time window. Several previous electrophysiological studies (Bader et al, ; Diana et al, ; Guillaume & Etienne, ; Jäger et al, , ; Kamp et al, ; Kriukova et al, ; Li, Mao, Wang, & Guo, ; Lyu, Wang, Mao, Li, & Guo, ; Rhodes & Donaldson, ; Tibon, Ben‐Zvi, & Levy, ; Tibon, Gronau et al, ; Zheng et al, ) also suggest that early retrieval processes are selectively enabled for unitized but not for nonunitized pair associates. However, only two prior electrophysiological investigations of unitization effects at the higher end of the LOU continuum (where stimuli already bear strong associative relationships prior to the experiment) employed a design that allows conclusive attribution of mnemonic effects to associative recognition (Kriukova et al, , Zheng et al, ).…”

Intercomparison of the POES/MEPED Loss Cone Electron Fluxes With the CMIP6 Parametrization

“…As a first step, the overall performance of the Ap model with regard to reproducing the general flux strength is tested. The left column of Figure 1 illustrates the electron flux distribution with respect to different L shells and Ap values as given by the Ap model functions (van de Kamp et al, 2016). The lower energy limits are given as >43 and >114 keV in order to match the MEPED optimized energy thresholds using the energy spectral gradient provided by the model.…”

“…The modeled fluxes grow stronger with increasing Ap values reaching red colors corresponding to flux levels of >5·10 5 cm −2 ·sr −1 ·s −1 for >43 keV and >1·10 4 cm −2 ·sr −1 ·s −1 for >114 keV. In order to compare the MEPED LC fluxes with the model, daily fluxes were determined in accordance with the approach described in van de Kamp et al (2016). Data were binned into 3-hr intervals and L shell bin widths of 0.5.…”

“…It is, however, not always well communicated that the applied fluxes are lower estimates and that the extent of the underestimation is unclear. Van de Kamp et al (2016) provide a model for 30-1,000 keV energetic electron precipitation (EEP) based on the 0°detector in the period 2002-2012 and empirically described plasmasphere structure. The model is both scaled to daily resolution of the geomagnetic index Ap or Dst.…”

“…In order to assess the accuracy of the van de Kamp et al (2016) Ap model, we compare the modeled electron fluxes with the LC fluxes estimated by Nesse . By combining the electron fluxes measured by both the 0 o and 90 o MEPED telescopes with electron pitch angle distributions from theory of wave-particle interactions in the magnetosphere (Kennel & Petschek, 1966;Theodoridis & Paolini, 1967), a complete bounce LC flux is constructed for each of the electron energy channels >43 keV, >114 keV, and >292 keV (see Table 1; Ødegaard et al, 2017).…”