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Human body movements are supported by a somatotopic map, primary motor cortex (M1), that is found along the precentral gyrus. Recent evidence has suggested two further motor maps that span the lateral occipitotemporal cortex (LOTC) and the precuneus. Confirmation of these maps is important, as they influence our understanding of the organization of motor behavior, for example by revealing how visual- and motor-related activity interact. However, evidence for these recently proposed maps is limited. We analyzed an open functional MRI (fMRI) dataset of 62 participants who performed 12 different body part movements. We analyzed the magnitude of responses evoked by movements with novel quantitative indices that test for maplike organization. We found strong evidence for bilateral somatotopic maps in precentral and postcentral gyri. In LOTC, we found much weaker responses to movement and little evidence of somatotopy. In the precuneus, we found only limited evidence for somatotopy. We also adopted a background connectivity approach to examine correlations between M1, LOTC, and the precuneus in the residual time series data. This revealed a ventral-posterior/dorsal-anterior distinction in the connectivity between precuneus and M1, favoring the head and arms, respectively. Posterior right hemisphere LOTC showed some evidence of preferential connectivity to arm-selective regions of M1. Overall, our results do not support the existence of a somatotopic motor map in LOTC but provide some support for a coarse map in the precuneus, especially as revealed in connectivity patterns. These findings help clarify the organization of human motor representations beyond the precentral gyrus. NEW & NOTEWORTHY: We investigated previous claims about the existence of somatotopic motor maps in the human lateral occipitotemporal cortex (LOTC) and the precuneus, in comparison to known maps in the precentral and postcentral gyri. Consistent with previous findings, we identified clear somatotopic motor maps in the latter two regions. With multiple quantitative measures of activity and connectivity, however, we found no evidence for a map in the LOTC and limited evidence for a map in the precuneus. [ABSTRACT FROM AUTHOR]

AI models of reminding (ARCS, MAC/FAC) that predict that memory access is influenced by analogical similarity are tested. In Experiment 1, subjects initially studied a set of 12 target stories. Later, subjects read 10 other cue stories and were asked to write down the stories they were reminded of from the first set. Cue stories were associated with either an analogous and disanalogous target (competition condition), an analogous target (singleton condition), or a disanalogous target (singleton condition). An effect of analogical similarity was found only in the competition condition. Experiment 2 used the same design but targets and cues were simple subject-verb-object sentences. Cue sentences shared similar nouns and verbs with target sentences. Materials were constructed such that associated nouns either consistently mapped or cross-mapped between cues and targets. Consistent-mapped sentences were recalled more than cross-mapped sentences in both conditions. Issues for future research are addressed.

An important question for cognitive models of human memory is the question of how analogical similarity affects memory retrieval. While the importance of surface lexical and semantic similarities between reminding cues and memory targets has been well-documented, clear empirical evidence that human memory retrieval is influenced by analogy has proven difficult to demonstrate. W e report two experiments in which subjects used a series of single sentences as reminding cues for previously-seen mini-texts. Some cue sentences contained noims and verbs that were hyponyms (i.e., words subordinate to the same category) of those in corresponding target sentences presented in one or two earlier passages. The role of analogical similarity in reminding was examined by varying the correspondence of noun case-role assignments of cue/target homonyms. Results indicate that retrieval competition and analogical similarity influence reminding. Recall of semanticallyrelated passages was significantly greater for structurally consistent (i.e., analogical) cues. Retrieval access was impaired when two semantically related passages were present in memory. Access to the passage with analogical resemblance to the cue was decreased by retrieval competition to an extent consistent with a ratio rule.

Electrophysiological and functional neuroimaging evidence points to the existence of neural populations that respond strongly and selectively to the appearance of the human body and its parts. However, the relationship between ERP and fMRI markers of these populations remains unclear. Here we used a previously identified functional dissociation between two body-selective regions identified with fMRI (extrastriate body area or EBA; fusiform body area or FBA) in order to better understand the source of a body-selective N1 ERP component. Specifically, we compared the magnitude of the N1 elicited by images of fingers, hands, arms and bodies to that obtained for hierarchically-matched control stimuli. We found close agreement between the pattern of body-part selectivity exhibited by N1, and the pattern of BOLD selectivity elicited in a previous study by the same type of stimuli in EBA (in contrast to FBA). We interpret these findings as evidence for EBA as the primary generator of the body-selective N1 component. Our results are an example of the use of functional criteria to distinguish among the possible neural sources of ERP markers. (Contains 4 figures.)

Evidence from neuropsychology suggests that the distinction between animate and inanimate kinds is fundamental to human cognition. Previous neuroimaging studies have reported that viewing animate objects activates ventrolateral visual brain regions, whereas inanimate objects activate ventromedial regions. However, these studies have typically compared only a small number of animate and inanimate kinds (e.g. animals and tools) and some evidence indicates that task demands determine whether these effects occur at all. In the current study we test whether a lateral-medial animacy bias is evident across a variety of stimuli, and across different tasks (matching two stimuli at a general, intermediate and exemplar level). Images of objects were presented sequentially in pairs, and match/mismatch judgements were made at different levels in different scans. The fMRI data showed ventrolateral activation for animate objects and ventromedial activation for inanimate objects. Additional analyses within these regions revealed no main effect of task, and no interactions between task and animacy. Furthermore, there were no subpopulations of voxels in any of the regions of interest that showed a significant task by animacy interaction. We conclude that ventral animate/inanimate category biases do not always depend on top-down task orientation. Furthermore, we consider whether the animate and inanimate activations reflect biases in the non-preferred responses of strongly category-selective regions such as the fusiform face area or the parahippocampal place area. (Contains 4 figures and 2 tables.)

Functional neuroimaging research has shown that certain classes of visual stimulus selectively activate focal regions of visual cortex. Specifically, cortical areas that generally and selectively respond to faces (Kanwisher, N., McDermott, J., & Chun, M. M. (1997). The fusiform face area: a module in human extrastriate cortex specialized for face perception. Journal of Neuroscience, 17(11), 4302-4311; Puce, A., Allison, T., Asgari, M., Gore, J. C., & McCarthy, G. (1996). Differential sensitivity of human visual cortex to faces, letterstrings, and textures: a functional magnetic resonance imaging study. Journal of Neuroscience, 16(16), 5205-5215.) and to the human body (Downing, P. E., Jiang, Y., Shuman, M., & Kanwisher, N. (2001). A cortical area selective for visual processing of the human body. Science, 293(5539), 2470-2473.) have recently been described using fMRI. A parallel body of research has focused on the ability of faces to "capture" the focus of attention, compared to other kinds of objects (Lavie, N., Ro, T., & Russell, C. (2003). The role of perceptual load in processing distractor faces. Psychological Science, 14(5), 510-515; Ro, T., Russell, C., & Lavie, N. (2001). Changing faces: a detection advantage in the flicker paradigm. Psychological Science, 12(1), 94-99; Vuilleumier, P. (2000). Faces call for attention: evidence from patients with visual extinction. Neuropsychologia, 38(5), 693-700.). The present study uses Mack and Rock's "inattentional blindness" paradigm to investigate whether unexpected, task-irrelevant human body stimuli capture awareness when attention is occupied by a primary task (Mack, A., & Rock, I. (1998). Inattentional blindness. London: MIT Press). Silhouettes and stick figures of human bodies, and silhouettes of hands, were compared to control stimuli including object silhouettes, object stick figures, and scrambled silhouettes of bodies, body parts, and objects. Participants were significantly better able to detect a human figure relative to the control stimuli. These results suggest that the human body, like the face, may be prioritized for attentional selection. More generally, they are consistent with the proposal that the visual system assigns attentional priority to types of stimuli that are also represented in strongly selective cortical regions.

Functional magnetic resonance imaging (fMRI) was used to test predictions of the object-based theory that pre-attentive mechanisms section the visual array into objects, groups or surfaces, which act as visual attentional targets. Attending to one attribute of an object was found to enhance the neural representation of the attributed, and also of the other attribute of the same object.