Generalisation of fear and avoidance along a semantic continuum

Directly conditioned fear and avoidance readily generalises to dissimilar but conceptually related stimuli. Here, for the first time, we examined the conceptual/semantic generalisation of both fear and avoidance using real words (synonyms). Participants were first exposed to a differential fear conditioning procedure in which one word (e.g., “broth”; CS+) was followed with brief electric shock [unconditioned stimulus (US)] and another was not (e.g., “assist”; CS–). Next, an instrumental conditioning phase taught avoidance in the presence the CS+ but not the CS–. During generalisation testing, synonyms of the CS+ (e.g., “soup”; GCS+) and CS– (e.g., “help”; GCS–) were presented in the absence of shock. Conditioned fear and avoidance, measured via skin conductance responses, behavioural avoidance and US expectancy ratings, generalised to the semantically related, but not to the semantically unrelated, synonyms. Findings have implications for how natural language categories and concepts mediate the expansion of fear and avoidance repertoires in clinical contexts.     

Masked semantic priming effects from the prime's orthographic neighbours

The present research involved masked priming lexical decision experiments using, in the crucial condition, masked primes with an orthographic neighbour that was semantically related to the target. Regardless of the lexicality of the prime, a significant priming effect was observed when the relatedness proportion (RP, that is, the proportion of primes and targets that were directly related on the “word” trials) was 2/3 (Experiments 1 and 2). No effect emerged, however, when the RP was 0 (Experiment 3). These results indicate that lexical/semantic activation arises automatically for both the prime and its neighbours. This activated lexical/semantic information appears to be evaluated together with the lexical/semantic information activated by the target, creating a decision bias during the decision-making process, but only when that information often provides a clue as to the nature of the correct decision. Our results, therefore, also provide support for the retrospective account of masked semantic priming.     

Global and Local Feature Distinctiveness Effects in Language Acquisition

Various aspects of semantic features drive early vocabulary development, but less is known about how the global and local structure of the overall semantic feature space influences language acquisition. A feature network of English words was constructed from a large database of adult feature production norms such that edges in the network represented feature distances between words (i.e., Manhattan distances of probability distributions of features elicited for each pair of words). A word's global feature distinctiveness is measured with respect to all other words in the network and a word's local feature distinctiveness is measured relative to words in sub-networks derived from clustering analyses. This paper investigates how feature distinctiveness of individual words at local and global scales of the network influences language acquisition. Regression analyses indicate that global feature distinctiveness was associated with earlier age of acquisition ratings, and was a stronger predictor of age of acquisition than local feature distinctiveness. These results suggest that the global structure of the semantic feature network could play an important role in language acquisition, whereby globally distinctive concepts help to structure vocabulary development over the lifespan.     

The robustness of false memory for emotional pictures

Emotional material is commonly reported to be more accurately recognised; however, there is substantial evidence of increased false alarm rates (FAR) for emotional material and several reports of stronger influences on response bias than accuracy. This pattern is more frequently reported for words than pictures. Research on the mechanisms underlying bias differences has mostly focused on word lists under short retention intervals. This article presents four series of experiments examining recognition memory for emotional pictures while varying arousal and the control over the content of the pictures at two retention intervals, and one study measuring the relatedness of the series picture sets. Under the shorter retention interval, emotion increased false alarms and reduced accuracy. Under the longer retention interval emotion increased hit rates and FAR, resulting in reduced accuracy and/or bias. At both retention intervals, the pattern of valence effects differed based on the arousal associated with the picture sets. Emotional pictures were found to be more related than neutral pictures in each set; however, the influence of relatedness alone does not provide an adequate explanation for all emotional differences. The results demonstrate substantial emotional differences in picture recognition that vary based on valence, arousal and retention interval.     

Does Semantics Need Normativity? Comments on Allan Gibbard,Meaning and Normativity

In the book Gibbard proposes, first, that statements about meaning are normative statements and, second, that they can be given an expressivist treatment, along the lines of Gibbard’s preferred metaethics. In my paper, I examine the first step: The claim that meaning statements are to be construed as being normative, as involving ‘oughts’. Gibbard distinguishes two versions of the normativity of meaning thesis – a weak version, according to which every means implies an ought, and a strong version, according to which for every means, there is an ought that implies it. I argue that neither thesis withstands scrutiny. The weak thesis depends on assumptions about the notion of semantic correctness that the anti-normativist rejects, and the strong thesis does not solve the problems Gibbard wants it to solve: the problems of indeterminacy and meaning skepticism. I conclude that semantics does not need normativity.     

When ancestral heritage is a source of discomfort: culture, pre-object relatedness, and self-alienation

The ancestral claims on an individual can evoke mental conflict when they involve separating from an ethnic group whose beliefs and customs are devalued by the dominant culture. However, these claims are engraved on the psyche early in development by caretakers to the level of pre-object relatedness, where contents and affect tones are implicit and may be unavailable for later psychoanalytical interventions. In addition, as the anthropologist Clifford Geertz notes, one's culture of origin precedes the development of psyche and creates its own set of claims that must be renegotiated when one encounters a different domain of cultural symbols, a confrontation that can produce psychological dissonance and self-alienation. In this paper, three cases are examined in which mental conflicts were evoked by attempts at divesting ancestral claims in response to conscious efforts to assimilate into the dominant culture. These patients suffered from separation guilt and unstable self-esteem and reported dream imagery suggesting psychological imbalance. The requirement to carefully delineate the ancestral claims on psyche as well as those contents and affects that may not be accessible to therapeutic intervention is emphasized, and the importance of compromise and acceptance with respect to the psychological demands of the unconscious are considered.     

The question shapes the answer: the neural correlates of task differences reveal dynamic semantic processing

Task effects in semantic processing were investigated by contrasting the neural activation associated with two semantic categorization tasks (SCT) using event-related fMRI. The two SCTs involved different decision categories: is it an animal? vs. is it a concrete thing? Participants completed both tasks and, across participants, the same core set of items were presented in both tasks. Results showed task differences in the neural activation associated with these items: in the animal SCT there was greater activation in a number of frontal and temporal regions, including left superior and middle temporal gyri, while in the concrete SCT there was greater activation in left medial frontal gyrus and bilaterally in the precentral gyri. These results are interpreted as evidence of top-down modulation of semantic processing; participants make adjustments to optimize performance in a given task and these adjustments have consequences for the activation observed.     

Semantic interference during object naming in agrammatic and logopenic primary progressive aphasia (PPA)

This study examined the time course of object naming in 21 individuals with primary progressive aphasia (PPA) (8 agrammatic (PPA-G); 13 logopenic (PPA-L)) and healthy age-matched speakers (n = 17) using a semantic interference paradigm with related and unrelated interfering stimuli presented at stimulus onset asynchronies (SOAs) of −1000, −500, −100 and 0 ms. Results showed semantic interference (SI) (i.e. significantly slower RTs in related compared to unrelated conditions) for all groups at −500, −100 and 0 ms, indicating timely spreading activation to semantic competitors. However, both PPA groups showed a greater magnitude of SI than normal across SOAs. The PPA-L group and six PPA-G participants also evinced SI at −1000 ms, suggesting an abnormal time course of semantic interference resolution, and concomitant left hemisphere cortical atrophy in brain regions associated with semantic processing. These subtle semantic mapping impairments in non-semantic variants of PPA may contribute to the anomia of these patients.     

How the brain responds to any: an MEG study

The word any may appear in some sentences, but not in others. For example, any is permitted in sentences that contain the word nobody, as in Nobody ate any fruit. However, in a minimally different context any seems strikingly anomalous: ^*Everybody ate any fruit. The aim of the present study was to investigate how the brain responds to the word any in such minimally different contexts - where it is permitted (licensed) and where it is not permitted (unlicensed). Brain responses were measured from adult readers using magnetoencephalography (MEG). The results showed significantly larger responses to permissible contexts in the left posterior temporal areas between 400-500 ms and 590-660 ms. These results clarify the anatomy and timing of brain processes that contribute to our judgment that a word such as any is or is not permitted in a given context.