Acoustic mechanisms of note-type perception in black-capped chickadee (Poecile atricapillus) calls

Acoustic communication in black-capped chickadees (Poecile atricapillus) has been studied intensively, the "chick-a-dee" call being among the most well described. This call consists of 4 note types; chickadees perceive these notes as open-ended categories and do so in a continuous manner, with As more similar to Bs and Bs more similar to Cs. Acoustic features contributing to the note-type differentiation are unknown. Recent analyses suggested that certain acoustic features may play a role in note-type classification. Here, the authors tested black-capped chickadees in an operant-conditioning paradigm to determine which features were controlling note-type perception. The results suggest that the note pitch and the frequency modulation in the initial portion of the note control the perception of note types.     

Distance,Contact, and Intergenerational Relationships: Grandparents and Adult Grandchildren from an International Perspective

In previous studies of intergenerational relationships, geographic distance has been considered the most obvious factor influencing opportunity for frequency of contact between grandparents and grandchildren. This study presents findings from a survey of 70 international college students in the Unites States regarding perceived grandparental influence and relationship satisfaction with their “closest” grandparent. Results showed that participants' perceived influence of grandparents and relationship satisfaction was maintained despite decreased contact between grandparents and grandchildren. In addition, grandchildren who initiated contact were found to have a significant impact on relationship satisfaction. This study provides an understanding of distance, contact, and intergenerational relationships in an international context.     

Activation of group II metabotropic glutamate receptors induces depotentiation in amygdala slices and reduces fear-potentiated startle in rats

There is a close correlation between long-term potentiation (LTP) in the synapses of lateral amygdala (LA) and fear conditioning in animals. We predict that reversal of LTP (depotentiation) in this area of the brain may ameliorate conditioned fear. Activation of group II metabotropic glutamate receptors (mGluR II) with DCG-IV induces depotentiation in the LA. The induction of depotentiation is independent of NMDA receptors, L-type Ca++ channels, and calcineurin activity, but requires presynaptic activity and extracellular Ca++. (2S,2'R,3'R)-2-(2',3'-dicarboxycyclopropyl)glycine (DCG-IV) depotentiation is accompanied by a decrease in the frequency but not the amplitude of miniature excitatory post-synaptic currents (mEPSCs) and could be mimicked by endogenously released glutamate. DCG-IV inhibited the release of glutamate evoked by 4-AP but not that evoked by ionomycin, suggesting that the effect of DCG-IV is not mediated by an action downstream of Ca++ entry. Intra-amygdala infusion of mGluR II agonist blocks the consolidation of fear memory measured with fear-potentiated startle. Taken together, the present results characterize the properties of DCG-IV depotentiation and reveal a close parallel between depotentiation in the amygdala slice and the reduction of conditioned fear in animals.     

Distinctiveness,typicality, and recollective experience in face recognition: A principal components analysis

In this study, participants rated previously unseen faces on six dimensions: familiarity, distinctiveness, attractiveness, memorability, typicality, and resemblance to a familiar person. The faces were then presented again in a recognition test in which participants assigned their positive recognition decisions to either remember (R), know (K), or guess categories. On all dimensions except typicality, faces that were categorized as R responses were associated with significantly higher ratings than were faces categorized as K responses. Study ratings for R and K responses were then subjected to a principal components analysis. The factor loadings suggested that R responses were influenced primarily by the distinctiveness of faces, but K responses were influenced by moderate ratings on all six dimensions. These findings indicate that the structural features of a face influence the subjective experience of recognition.     

The input to verb learning in Mandarin Chinese: a role for syntactic bootstrapping

The authors investigated the role of syntax in verb learning in Mandarin Chinese, which allows pervasive ellipsis of noun arguments. Two questions were investigated using the Beijing corpus on CHILDES: (a) Does the input to young children manifest syntactic-semantic correspondences as needed for acquiring verb meanings? (b) Are verbs presented in multiple frames? Over 6,000 child-directed utterances were parsed. Analyses revealed that transitive verbs, motion verbs, and internal/communication verbs were distinguished syntactically; moreover, the 60 target verbs were used in multiple sentence frames. These findings support a role for syntactic bootstrapping in Mandarin verb learning.     

Mea culpa: predicting stock prices from organizational attributions

People's causal attributions for events in their lives have been shown to relate to individual and interpersonal outcomes. Groups and organizations also make causal attributions, and this article examines whether their publicly communicated attributions predict organizational-level outcomes. By content analyzing attributions contained in corporate annual reports from 14 companies during a 21-year period, the authors found that organizations that made "self disserving" attributions- internal and controllable attributions for negative events-had higher stock prices 1 year later. The authors argue that claiming personal responsibility for negative events made the organizations appear more in control, leading to more positive impressions.     

Use of phonological codes for Chinese characters: evidence from processing of parafoveal preview when reading sentences

The role of phonological coding for character identification was examined with the benefit of processing parafoveal characters in eye fixations while reading Chinese sentences. In Experiment 1, the orthogonal manipulation of phonological and orthographic similarity can separate two types of phonological benefits for homophonic previews, according to whether these previews share the same phonetic radical with the targets or not. The significant phonological benefits indicate that phonological coding is activated early when the character is in the parafovea. Experiment 2 manipulated the character's consistency value and found that the phonological preview benefits are reliable only when the targets are high consistency characters. The results of two experiments suggest that phonological computation is rapid and early at both character and radical levels for Chinese character identification.     

Stimulus-set location does not affect orthogonal stimulus-response compatibility

In two-choice tasks for which stimuli and responses vary along orthogonal dimensions, one stimulus-response mapping typically yields better performance than another. For unimanual movement responses, the hand used to respond, hand posture (prone or supine), and response eccentricity influence this orthogonal stimulus-response compatibility (SRC) effect. All accounts of these phenomena attribute them to response-related processes. Two experiments examined whether manipulation of stimulus-set position along the dimension on which the stimuli varied influences orthogonal SRC in a manner similar to the way that response location does. The experiments differed in whether the stimulus dimension was vertical and the response dimension horizontal, or vice versa. In both experiments, an advantage of mapping up with right and down with left was evident for several response modes, and stimulus-set position had no influence on the orthogonal SRC effect. The lack of effect of stimulus-set position is in agreement with the emphasis that present accounts place on response-related processes. We favor a multiple asymmetric codes account, for which the present findings imply that the polarity of stimulus codes does not vary across task contexts although the polarity of response codes does.