Tobacco and alcohol tax relationships with suicide in Switzerland

Previous research has shown an empirical link between tobacco and alcohol use and suicide. If tobacco and alcohol use contribute to suicidal behaviors, then policies designed to reduce the tobacco and alcohol consumption may succeed in reducing suicides as well. To test this hypothesis, correlations for suicide rates with alcohol consumption, taxes on alcohol and tobacco in Switzerland were examined using sets of time-series data from Switzerland in 1965-1994. The tax on tobacco correlated significantly negatively with male standardized suicide rate. The tax on alcohol also correlated significantly with male standardized suicide rate in an autoregressive model. On the other hand, significant relationships with female suicide rate were not found. Policies designed to reduce tobacco consumption are consistent with a benefit of reducing suicides, particularly for men in this sample.     

Rapid acceleration of the lower arm correlates with agonist EMGs during the initial phase

Fifty-eight healthy subjects made rapid elbow extensions to a target over 54 degrees. Angular acceleration was measured and surface electromyograms (EMGs) were recorded from the antagonistic muscles using monopolar rather than bipolar electrode configurations. Marked individual differences were found in the peak value of the first derivative of acceleration (dAcc/dt_Pk). The dAcc/dt_Pk correlated with both quantitative and qualitative properties of the agonist EMGs, but not with those of the antagonist EMG. The agonist EMGs, integrated until the moment of dAcc/dt_Pk, were positively correlated with dAcc/dt_Pk. The interval between EMG onset and EMG peak decreased with increasing dAcc/dt_Pk. The duration of the initial negative phase in the EMGs, which was considered to index the time required to recruit high-threshold MUs, decreased with increasing dAcc/dt_Pk. The results indicate that the ability to rapidly accelerate the lower arm varies across subjects, probably due in part to individual differences in the neural capacity to drive the agonists.     

Effects of nonconscious perception on motor response

The present study reviews the literature on the empirical evidence for the dissociation between perception and action. We first review several key studies on brain-damaged patients, such as those suffering from blindsight and visual/tactile agnosia, and on experimental findings examining pointing movements in normal people in response to a nonconsciously perceived stimulus. We then describe three experiments we conducted using simple reaction time (RT) tasks with backward masking, in which the first (weak) and second (strong) electric stimuli were consecutively presented with a 40-ms interstimulus interval (ISI). First, we compared simple RTs for three stimulus conditions: weak alone, strong alone, and double, i.e., weak plus strong (Experiment 1); then, we manipulated the intensity of the first stimulus from the threshold (T) to 1.2T and 2T, with the second stimulus at 4T (Experiment 2); finally, we tested three different ISIs (20, 40, and 60 ms) with the stimulus intensities at 1.2T and 4T for the first and second stimuli (Experiment 3). These experiments showed that simple RTs were shorter for the double condition than for the strong-alone condition, indicating that motor processes under the double condition may be triggered by sensory inputs arising from the first stimulus. Our results also showed that the first stimulus was perceived without conscious awareness. These findings suggested that motor processes may be dissociated from conscious perceptual processes and that these two processes may not take place in a series but, rather, in parallel. We discussed the likely mechanisms underlying nonconscious perception and motor response to a nonconsciously perceived stimulus.     

Pattern evolution of crystalline Ge aggregates during annealing of an Al/Ge bilayer film deposited on a SiO2 substrate

When an Al/Ge bilayer film deposited on a SiO2 substrate is annealed at 373- 398 K, Ge atoms diffuse out from the inner amorphous Ge layer and spread over the free surface of the outer Al layer to form crystalline Ge aggregates exhibiting complex substructures. Scanning electron microscopy observations indicate that the activation energy for the pattern evolution of Ge aggregates on the free surface because of annealing is 1.56 eV which is about half the activation energy for crystallization of amorphous Ge.     

Microstructural characterization and high-temperature strength of hot-pressed silicon nitride ceramics with Lu2O3 additives

The microstructures of two hot-pressed Si₃N₄ ceramics, with 3.33 and 12.51 wt% Lu₂O₃ additive, have been characterized using transmission electron microscopy. The microstructures of both samples consisted of elongated β-Si₃N₄ grains and a secondary phase, contained in pockets surrounded by the grains, with a crystalline or amorphous form. In the 3.33 wt% Lu₂O₃-containing Si₃N₄ ceramic, all the multiple-grain junctions were completely crystalline while, in the 12.51 wt% Lu₂O₃-containing Si₃N₄ ceramic, approximately half the junctions were devitrified. A thin intergranular amorphous film present between the two-grain boundary was common; however, a film-free grain boundary was observed in the 12.51 wt% Lu₂O₃ sample. The film-free grain boundary was determined to be approximately 35%. Both ceramics fractured in four-point flexure between 1200 and 1600°C. Their high-temperature strength is closely associated with the nature of the grain-boundary phase formed during the sintering process.     

Action enhances auditory but not visual temporal sensitivity

People naturally dance to music, and research has shown that rhythmic auditory stimuli facilitate production of precisely timed body movements. If motor mechanisms are closely linked to auditory temporal processing, just as auditory temporal processing facilitates movement production, producing action might reciprocally enhance auditory temporal sensitivity. We tested this novel hypothesis with a standard temporal-bisection paradigm, in which the slope of the temporal-bisection function provides a measure of temporal sensitivity. The bisection slope for auditory time perception was steeper when participants initiated each auditory stimulus sequence via a keypress than when they passively heard each sequence, demonstrating that initiating action enhances auditory temporal sensitivity. This enhancement is specific to the auditory modality, because voluntarily initiating each sequence did not enhance visual temporal sensitivity. A control experiment ruled out the possibility that tactile sensation associated with a keypress increased auditory temporal sensitivity. Taken together, these results demonstrate a unique reciprocal relationship between auditory time perception and motor mechanisms. As auditory perception facilitates precisely timed movements, generating action enhances auditory temporal sensitivity.     

Structural-functional correlations between hippocampal volume and cortico-limbic emotional responses in depressed children

Although hippocampal atrophy and altered functional brain responses to emotional stimuli have been found in major depressive disorder (MDD), the relationship between the two is not yet well understood. The present study focused on children with and without a history of preschool onset MDD (PO-MDD) and directly examined the relations between hippocampal volume and functional brain activation to affect-eliciting stimuli. Children completed annual diagnostic assessments starting at preschool. When children were school-aged, high-resolution structural MRI and task-related functional MRI data were acquired from N = 64 nonmedicated children. During fMRI, subjects were shown emotional faces. Results from the total sample indicated that smaller bilateral hippocampal volumes were associated with greater cortico-limbic (e.g., amygdala, hippocampus, dorsolateral prefrontal cortex) activation to sad or negative faces versus neutral faces. Left hippocampal volume was negatively associated with the cortico-limbic activation in both the PO-MDD and healthy children. Right hippocampal volume was negatively correlated with amygdala responses in the PO-MDD group, but not in the healthy comparison group. These findings suggest that there may be important interrelationships between reduced hippocampal volume and hyperactivation of brain responses in children, both those with and those without a history of PO-MDD.     

The association of religiosity,spirituality, and ethnic background with ego-pathology in acute schizophrenia

Studies have highlighted the impact of ego-consciousness, religiosity and spirituality on psychotic symptoms, although so far no study has investigated if and how these factors may be interrelated. In this exploratory cross-sectional study, involving 42 patients with a diagnosis of acute paranoid schizophrenia (DSM-IV), we assessed religiosity (Religious Orientation Test) spirituality (Spiritual Transcendence Scale) and ego-pathology (Ego Pathology Inventory) and analysed any relationship with these and psychopathological symptoms (Positive and Negative Symptom Scale). The subjects were divided into four ethnic groups (Caucasian, Afro-Caribbean, African, and Asian) and a structured, qualitative interview on religious needs and self-concepts was also conducted. Using a multivariate analysis, we found statistically significant negative associations between the scores on ego and common pathology and religiosity and spirituality as covariates. This was seen across all ethnic groups. The findings are discussed in respect of the potential clinical importance of ethnic, religious and spiritual factors for assessment and management of patients with schizophrenia.     

Short report: The effect of expertise in hiking on recognition memory for mountain scenes

The nature of an expert memory advantage that does not depend on stimulus structure or chunking was examined, using more ecologically valid stimuli in the context of a more natural activity than previously studied domains. Do expert hikers and novice hikers see and remember mountain scenes differently? In the present experiment, 18 novice hikers and 17 expert hikers were presented with 60 photographs of scenes from hiking trails. These scenes differed in the degree of functional aspects that implied some action possibilities or dangers. The recognition test revealed that the memory performance of experts was significantly superior to that of novices for scenes with highly functional aspects. The memory performance for the scenes with few functional aspects did not differ between novices and experts. These results suggest that experts pay more attention to, and thus remember better, scenes with functional meanings than do novices.     

Object-based auditory facilitation of visual search for pictures and words with frequent and rare targets

Auditory and visual processes demonstrably enhance each other based on spatial and temporal coincidence. Our recent results on visual search have shown that auditory signals also enhance visual salience of specific objects based on multimodal experience. For example, we tend to see an object (e.g., a cat) and simultaneously hear its characteristic sound (e.g., “meow”), to name an object when we see it, and to vocalize a word when we read it, but we do not tend to see a word (e.g., cat) and simultaneously hear the characteristic sound (e.g., “meow”) of the named object. If auditory–visual enhancements occur based on this pattern of experiential associations, playing a characteristic sound (e.g., “meow”) should facilitate visual search for the corresponding object (e.g., an image of a cat), hearing a name should facilitate visual search for both the corresponding object and corresponding word, but playing a characteristic sound should not facilitate visual search for the name of the corresponding object. Our present and prior results together confirmed these experiential association predictions. We also recently showed that the underlying object-based auditory–visual interactions occur rapidly (within 220 ms) and guide initial saccades towards target objects. If object-based auditory–visual enhancements are automatic and persistent, an interesting application would be to use characteristic sounds to facilitate visual search when targets are rare, such as during baggage screening. Our participants searched for a gun among other objects when a gun was presented on only 10% of the trials. The search time was speeded when a gun sound was played on every trial (primarily on gun-absent trials); importantly, playing gun sounds facilitated both gun-present and gun-absent responses, suggesting that object-based auditory–visual enhancements persistently increase the detectability of guns rather than simply biasing gun-present responses. Thus, object-based auditory–visual interactions that derive from experiential associations rapidly and persistently increase visual salience of corresponding objects.