Depression After Mild Traumatic Brain Injury: A Review of Current Research

Research pertaining to the occurrence of depression and/or depression symptomatology after a Mild Traumatic Brain Injury (MTBI) was reviewed. We found that methodological differences such as the criteria used to assess MTBI and depression, time that elapsed since brain injury, and control group variations confounded comparisons across studies. Nevertheless, the studies are consistent with at least a 35% prevalence of, and left frontal damage with depression after MTBI, an overlap of symptoms of depression and Postconcussion Syndrome (PCS), and indicate that depression can continue for many years following the injury. Our conclusion is that MTBI is the triggering event for a set of pathophysiological changes and a concomitant depressive episode in a vulnerable subset of the population. Due to a paucity of research, it cannot be definitively concluded that the underlying substrates of depression seen after MTBI and clinical depression are the same. Implications for future investigations are discussed.     

Beyond Pleasure: Exploring the Eudaimonic Entertainment Experience

We examine the notion of eudaimonic entertainment during exposure to a sad but meaningful movie, using a new measure consisting of 5 dimensions derived from research on positive psychology. We, thereby, transfer the conception of eudaimonic well‐being to the conception of entertainment. Results of a confirmatory factor analysis show that the 5 dimensions can be further condensed into 2 second‐order factors. We applied these new measures in a study in which the ending of a movie was manipulated (sad vs. happy). The results provide both discriminant and convergent validity and show that hedonic entertainment measures were affected by the manipulation, but that eudaimonic entertainment measures were unaffected. A second study provided further evidence for the validity of the construct.     

Stable unstable reliability theory

Classical reliability theory assumes that individuals have identical true scores on both testing occasions, a condition described as stable. If some individuals' true scores are different on different testing occasions, described as unstable, the estimated reliability can be misleading. A model called stable unstable reliability theory (SURT) frames stability or instability as an empirically testable question. SURT assumes a mixed population of stable and unstable individuals in unknown proportions, with w(i) the probability that individual i is stable. w(i) becomes i's test score weight which is used to form a weighted correlation coefficient r(w) which is reliability under SURT. If all w(i) = 1 then r(w) is the classical reliability coefficient; thus classical theory is a special case of SURT. Typically r(w) is larger than the conventional reliability r, and confidence intervals on true scores are typically shorter than conventional intervals. r(w) is computed with routines in a publicly available R package.     

Self-regulation and milestones of adult development: intimacy and generativity

In 2 separate studies, the idea is tested that the positive association between self-regulatory capacities and well-being is partly explained by the positive effect self-regulation has on the successful resolution of developmental crises in Eriksonian terms. In Study 1, attentional control, intimacy, and subjective well-being are assessed in 177 young adults. Results show that attentional control fosters intimacy, which in turn is beneficial to subjective well-being. Study 2 has a longitudinal design: Action control, generativity, purpose in life, and Machiavellianism are measured in 163 adults with an interval of 18 months between the 2 testing occasions. Action control is found to promote the development of generative concern, which in turn increases purpose in life. The latter association, however, is further qualified by Machiavellian attitudes. Results are discussed with respect to the role of self-regulation in development and to belief in the species, which Erikson postulated to be active in the development of generativity.     

Perceiving age and gender in unfamiliar faces: an fMRI study on face categorization

Efficient processing of unfamiliar faces typically involves their categorization (e.g., into old vs. young or male vs. female). However, age and gender categorization may pose different perceptual demands. In the present study, we employed functional magnetic resonance imaging (fMRI) to compare the activity evoked during age vs. gender categorization of unfamiliar faces. In different blocks, participants performed age and gender classifications for old or young unfamiliar faces (50% female respectively). Both tasks elicited activations in the bilateral fusiform gyri (fusiform face area, FFA) and bilateral inferior occipital gyri (occipital face area, OFA). Importantly, the same stimuli elicited enhanced activation during gender as compared to age categorization. This enhancement was significant in the right FFA and the left OFA, and may be related to increased configural processing. Our findings replicate and extend recent work, and shows that the activation of core components of the face processing network is strongly dependent on task demands.     

The scene and the unseen: Manipulating photographs for experiments on change blindness and scene memory

The change blindness paradigm, in which participants often fail to notice substantial changes in a scene, is a popular tool for studying scene perception, visual memory, and the link between awareness and attention. Some of the most striking and popular examples of change blindness have been demonstrated with digital photographs of natural scenes; in most studies, however, much simpler displays, such as abstract stimuli or “free-floating” objects, are typically used. Although simple displays have undeniable advantages, natural scenes remain a very useful and attractive stimulus for change blindness research. To assist researchers interested in using natural-scene stimuli in change blindness experiments, we provide here a step-by-step tutorial on how to produce changes in natural-scene images with a freely available image-processing tool (GIMP). We explain how changes in a scene can be made by deleting objects or relocating them within the scene or by changing the color of an object, in just a few simple steps. We also explain how the physical properties of such changes can be analyzed using GIMP and MATLAB (a high-level scientific programming tool). Finally, we present an experiment confirming that scenes manipulated according to our guidelines are effective in inducing change blindness and demonstrating the relationship between change blindness and the physical properties of the change and inter-individual differences in performance measures. We expect that this tutorial will be useful for researchers interested in studying the mechanisms of change blindness, attention, or visual memory using natural scenes.     

Differential neuronal responses to the self and others in the extrastriate body area and the fusiform body area

The extrastriate body area (EBA) and the fusiform body area (FBA) are selectively activated by viewing human bodies. However, the role of these functionally defined brain areas in self-other discrimination is still unresolved. Thirty-one females were presented with 16 pictures of their own body and another body in a bikini and with scrambled images while fMRI was performed. Moreover, standardized stimulus material was used in order to localize the EBA and FBA. Region-of-interest analysis showed an enhanced BOLD response to the self-images relative to the non-self-images in the right EBA and FBA. The right EBA and FBA are activated differently by viewing oneself and others and might thus play a role in visual self-other discrimination.     

A Process Model of the Formation of Spatial Presence Experiences

In order to bridge interdisciplinary differences in Presence research and to establish connections between Presence and “older” concepts of psychology and communication, a theoretical model of the formation of Spatial Presence is proposed. It is applicable to the exposure to different media and intended to unify the existing efforts to develop a theory of Presence. The model includes assumptions about attention allocation, mental models, and involvement, and considers the role of media factors and user characteristics as well, thus incorporating much previous work. It is argued that a commonly accepted model of Spatial Presence is the only solution to secure further progress within the international, interdisciplinary and multiple-paradigm community of Presence research.     

Evidence for precategorical extrinsic vowel normalization

Three experiments investigated whether extrinsic vowel normalization takes place largely at a categorical or a precategorical level of processing. Traditional vowel normalization effects in categorization were replicated in Experiment 1: Vowels taken from an [?]–[ε] continuum were more often interpreted as /?/ (which has a low first formant, F ₁) when the vowels were heard in contexts that had a raised F ₁ than when the contexts had a lowered F ₁. This was established with contexts that consisted of only two syllables. These short contexts were necessary for Experiment 2, a discrimination task that encouraged listeners to focus on the perceptual properties of vowels at a precategorical level. Vowel normalization was again found: Ambiguous vowels were more easily discriminated from an endpoint [ε] than from an endpoint [?] in a high-F ₁ context, whereas the opposite was true in a low-F ₁ context. Experiment 3 measured discriminability between pairs of steps along the [?]–[ε] continuum. Contextual influences were again found, but without discrimination peaks, contrary to what was predicted from the same participants’ categorization behavior. Extrinsic vowel normalization therefore appears to be a process that takes place at least in part at a precategorical processing level.