Table 1.
Summary of studies demonstrating multi-voxel decoding of information during visual working memory.
| Reference | Stimuli | Task-relevant information | Information decoded | Cortical regions allowing decoding |
|---|---|---|---|---|
| Ester et al. (2009) |  |
Orientation | Orientation | V1 |
| Harrison and Tong (2009) |  |
Orientation | Orientation | V1-V4 |
| Serences et al. (2009) |  |
a) Orientation b) Color |
a) Orientation b) Color |
a) V1 b) V1 |
| Christophel et al. (2012) |  |
Color pattern features | Color pattern identity | Early visual Posterior parietal |
| Jerde et al. (2012) |  |
Stimulus position | Left vs. right visual field | IPS2, IPS3 PCS |
| Linden et al. (2012) | Faces, Bodies, Scenes, Flowers | Exemplar identity | Category | Early visual Parahippocampal |
| Riggall and Postle (2012) |  |
a) Direction b) Speed |
a) Direction b) None |
a) Lateral occipital and temporal Medial occipital b) None |
| Sneve et al. (2012) |  |
a) Orientation b) Spatial frequency |
a) Orientation b) Spatial frequency |
a) V1-V4, LO1 b) V1, V2, V3A/B |
| Albers et al. (2013) |  |
Orientation | Orientation | Superior frontal gyrus Supramarginal gyrus V1-V3 |
| Emrich et al. (2013) |  |
Direction (cued by color) | Direction | Intraoccipital sulcus MT+ V1, V2 |
| Ester et al. (2013) |  |
Orientation | Orientation | V1, V2 |
| Han et al. (2013) | Faces Scenes | Exemplar identity | Category | Face-selective (FFA, OFA) Scene-selective (PPA, TOS, RSC) |
| Lee et al. (2013) |  |
a) Visual features b) Object name |
a) Object identity b) Object identity |
a) Posterior fusiform b) Lateral prefrontal |
| Nelissen et al. (2013) | Bodies, Faces, Houses | Exemplar identity | Category | Body-selective (EBA) Face-selective (FFA) Scene-selective (PPA) Object-selective (LOC) |
| Xing et al. (2013) |  |
Stimulus contrast | Stimulus contrast | V1, V2 |
| Christophel and Haynes (2014) |  |
Motion flowfield features | Motion flowfield identity | MT+ Posterior parietal Somatosensory |
| Naughtin et al. (2014) |  |
Exemplar identity with location | a) Identity of whole object set b) Number of objects |
a) Right dorsolateral prefrontal Premotor Left inferior frontal junction Anterior cingulate Superior medial frontal Left sIPS, ilPS Left LOC b) Left premotor sIPS, ilPS LOC |
| Pratte and Tong (2014) |  |
Position-specific orientation | Position-specific orientation | Contralateral V1, V2 Bilateral V3AB, V4 |
| Sprague et al. (2014) |  |
Stimulus position | Stimulus position | V1-V4, V3A IPS0-IPS3 Superior PCS |
| Sreenivasan et al. (2014b) | Faces Scenes | Exemplar identity | Category | Extrastriate visual cortex Lateral prefrontal cortex |
| Christophel et al. (2015) |  |
Color pattern features | Color pattern identity | Early visual Posterior parietal |
| Ester et al. (2015) |  |
Orientation | Orientation | Bilateral V1, Contralateral V4 Ipsilateral IPS2, IPS3 Prefrontal (incl. PCS) |
Studies are organized first by date and then alphabetically by first author. Across studies, a wide range of visual stimuli have been employed, from oriented gratings to high–level stimuli such as faces, objects and scenes. We list both the task-relevant information as well as the information that could be decoded. In many cases, these are the same, but there are also some studies in which the level of decoding differed from the task-relevant information. For example, in several of the studies employing high-level visual stimuli, the task required maintenance of information about within-category exemplars (e.g., different faces or scenes), but the decoding was at the level of category (e.g., faces vs. scenes). In the final column, we list the major regions in which information could be decoded. Studies differed in how regions were identified (e.g., region-of-interest vs. searchlight analyses) and we adopt the level of description provided in the published studies. We ascribe decoding to particular functional regions (e.g., V1, MT, FFA) only if those regions were specifically localized. Further, note that we do not give any information about tested regions in which information could not be decoded. For this information, we refer readers back to the original cited papers. EBA, Extrastriate Body Area; FFA, Fusiform Face Area; IPS0–4, retinotopically-defined regions in and around the intra-parietal sulcus (iIPS, inferior intra-parietal sulcus; sIPS, superior intra-parietal sulcus); LOC, object-selective Lateral Occipital Complex; LO1, lateral occipital area 1; MT+, motion-selective areas including both the middle temporal (MT) and medial superior temporal (MST) areas; OFA, Occipital Face Area; PCS, precentral sulcus; PPA, Parahippocampal Place Area; RSC, scene-selective Retro Splenial Complex; TOS, scene-selective region near the Transverse Occipital Sulcus; V1-V4, retinotopically defined regions of early visual cortex.