IntroductionWe evaluated whether transcranial direct current stimulation (tDCS) can improve picture-naming abilities in subjects with anomic Alzheimer or frontotemporal dementias.MethodsUsing a double-blind crossover design, 10 participants were trained on picture naming over a series of 10 sessions with either 30 minutes of anodal (2 mA) tDCS stimulation to the left inferior parieto-temporal region (P3) or sham stimulation. We evaluated performance on a trained picture-naming list, an equivalent untrained list, and additional neuropsychological tasks.ResultsParticipants improved significantly more receiving real stimulation rather than sham stimulation (40% vs. 19%, P < .01), lasting at least 2 weeks after stimulation. Furthermore, these participants showed a small increase for untrained picture-naming items and digit span when they received real stimulation but a decrease when sham stimulation was received.DiscussiontDCS stimulation has promise as a treatment for anomia in demented individuals and the effect can generalize to unstudied items as well as other cognitive abilities.

For 84 unique topic-vehicle pairs (e.g., knowledge-power), participants produced associated properties for the topics (e.g., knowledge), vehicles (e.g., power), metaphors (knowledge is power), and similes (knowledge is like power). For these properties, we also obtained frequency, saliency, and connotativeness scores (i.e., how much the properties deviated from the denotative or literal meaning). In addition, we examined whether expression type (metaphor vs. simile) impacted the interpretations produced. We found that metaphors activated more salient properties than did similes, but the connotativeness levels for metaphor and simile salient properties were similar. Also, the two types of expressions did not differ across a wide range of measures collected: aptness, conventionality, familiarity, and interpretive diversity scores. Combined with the property lists, these interpretation norms constitute a thorough collection of data about metaphors and similes, employing the same topic-vehicle words, which can be used in psycholinguistic and cognitive neuroscience studies to investigate how the two types of expressions are represented and processed. These norms should be especially useful for studies that examine the online processing and interpretation of metaphors and similes, as well as for studies examining how properties related to metaphors and similes affect the interpretations produced.

This eye movement study examined how people read nominal metaphors and similes in order to investigate how the surface form, or wording, of these expressions affected early processing. Participants silently read metaphors (knowledge is a river) and similes (knowledge is like a river). The identical words were used in the topic-vehicle pair (knowledge-river) in both conditions. Experiments 1 and 2 demonstrated longer reading times and a higher proportion of regressions in metaphors than in similes. Familiarity modulated later metaphor effects in Experiment 1, but not in Experiment 2. Reading ability did not modulate the metaphor effects in Experiment 2. Results indicate that readers revised their initial interpretation of metaphors before moving on to read new text. This suggests that readers did not initially hold figurative interpretations of apt nominal metaphors that are somewhat familiar. Metaphor interpretation may be fast, but it is not easy.