Aging and attentional guidance during visual search: functional neuroanatomy by positron emission tomography

Positron emission tomography (PET) was used to examine adult age differences in neural activation during visual search. Target detection was less accurate for older adults than for younger adults, but both age groups were successful in using color to guide attention to a subset of display items. Increasing perceptual difficulty led to greater activation of occipitotemporal cortex for younger adults than for older adults, apparently as the result of older adults maintaining higher levels of activation within the easier task conditions. The results suggest that compensation for age-related decline in the efficiency of occipitotemporal cortical functioning was implemented by changes in the relative level of activation within this visual processing pathway, rather than by the recruitment of other cortical regions.     

Post-training reversible inactivation of the hippocampus enhances novel object recognition memory

Research on the role of the hippocampus in object recognition memory has produced conflicting results. Previous studies have used permanent hippocampal lesions to assess the requirement for the hippocampus in the object recognition task. However, permanent hippocampal lesions may impact performance through effects on processes besides memory consolidation including acquisition, retrieval, and performance. To overcome this limitation, we used an intrahippocampal injection of the GABA agonist muscimol to reversibly inactivate the hippocampus immediately after training mice in two versions of an object recognition task. We found that the inactivation of the dorsal hippocampus after training impairs object-place recognition memory but enhances novel object recognition (NOR) memory. However, inactivation of the dorsal hippocampus after repeated exposure to the training context did not affect object recognition memory. Our findings suggest that object recognition memory formation does not require the hippocampus and, moreover, that activity in the hippocampus can interfere with the consolidation of object recognition memory when object information encoding occurs in an unfamiliar environment.The medial temporal lobe plays an important role in recognition memory formation, as damage to this brain structure in humans, monkeys, and rodents impairs performance in recognition memory tasks (for review, see Squire et al. 2007). Within the medial temporal lobe, studies have consistently demonstrated that the perirhinal cortex is involved in this form of memory (Brown and Aggleton 2001; Winters and Bussey 2005; Winters et al. 2007, 2008; Balderas et al. 2008). In contrast, the role of the hippocampus in object recognition memory remains a source of debate. Some studies have reported novel object recognition (NOR) impairments in animals with hippocampal lesions (Clark et al. 2000; Broadbent et al. 2004, 2010), yet others have reported no impairments (Winters et al. 2004; Good et al. 2007). Differences in hippocampal lesion size and behavioral procedures among the different studies have been implicated as the source of discrepancy in these findings (Ainge et al. 2006), but previous studies have not examined the consequences of environment familiarity on the hippocampus dependence of object recognition memory.Previous studies addressing the role of the hippocampus in recognition memory relied on permanent, pre-training lesions (Clark et al. 2000; Broadbent et al. 2004; Winters et al. 2004; Good et al. 2007). Permanent lesions inactivate the hippocampus not only during the consolidation phase, but also during habituation, acquisition, and memory retrieval, potentially confounding interpretation of the results. Furthermore, permanent lesion studies require long surgery recovery times during which extrahippocampal changes may emerge to mask or compensate for the loss of hippocampal function. To overcome these problems, we reversibly inactivated the dorsal hippocampus after training mice in two versions of the object recognition task. We infused muscimol, a γ-aminobutyric acid (GABA) receptor type A agonist, into the dorsal hippocampus immediately after training in an object-place recognition task or immediately following training in a NOR task. Consistent with previous studies (Save et al. 1992; Galani et al. 1998; Mumby et al. 2002; Stupien et al. 2003; Aggleton and Brown 2005), we observed that hippocampal inactivation impairs object-place recognition memory. Interestingly, we observed that the degree of contextual familiarity can influence NOR memory formation. We found that when shorter periods of habituation to the experimental environment were used, hippocampal inactivation enhances long-term NOR memory. In contrast, after extended periods of contextual habituation, long-term recognition memory was unaltered by hippocampal inactivation. Together these results suggest that if familiarization with objects occurs at a stage in which the contextual environment is relatively novel, the hippocampus plays an inhibitory role on the consolidation of object recognition memory. Supporting this view, we observed that object recognition memory is unaffected by hippocampal inactivation when initial exploration of the objects occurred in a familiar environment.     

Forensic neuropsychology: A reply to the method skeptics

Various critics or method skeptics have contended that clinical neuropsychology is not sufficiently developed as a science to be offered as evidence in legal or trial proceedings. The present article attempts to balance the extreme position of the method skeptics with an overview of legal and research data that support forensic applications of neuropsychology. It is suggested that clinical evidence can usefully inform legal decision making and that the modern trend has been for courts to be increasingly open to such expert testimony. The relevance of studies of clinical judgment, experience, and actuarial prediction is discussed, and neuropsychological assessment validity is specifically addressed. It is concluded that the arguments of the method skeptics should guide future research and caution forensic neuropsychologists, but that a retreat from the courtroom is unwarranted.     

Affective individual differences and startle reflex modulation

Potentiation of startle has been demonstrated in experimentally produced aversive emotional states, and clinical reports suggest that potentiated startle may be associated with fear or anxiety. To test the generalizability of startle potentiation across a variety of emotional states as well as its sensitivity to individual differences in fearfulness, the acoustic startle response of 17 high- and 15 low-fear adult subjects was assessed during fear, anger, joy, sadness, pleasant relaxation, and neutral imagery. Startle responses were larger in all aversive affective states than during pleasant imagery. This effect was enhanced among high fear subjects, although followup testing indicated that other affective individual differences (depression and anger) may also be related to increased potentiation of startle in negative affect. Startle latency was reduced during high- rather than low-arousal imagery but was unaffected by emotional valence.     

Face the noise: embodied responses to nonverbal vocalizations of discrete emotions

Extensive prior research has shown that the perception of an emotional facial expression automatically elicits a corresponding facial expression in the observer. Theories of embodied emotion, however, suggest that such reactions might also occur across expressive channels, because simulation is based on integrated motoric and affective representations of that emotion. In the present studies, we examined this idea by focusing on facial and experiential reactions to nonverbal emotion vocalizations. In Studies 1 and 2, we showed that both hearing and reproducing vocalizations of anger, disgust, happiness, and sadness resulted in specific facial behaviors, as well as congruent self-reported emotions (Study 2). In Studies 3 and 4, we showed that the inhibition of congruent facial actions impaired listeners' processing of emotion vocalizations (Study 3), as well as their experiences of a concordant subjective state (Study 4). Results support the idea that cross-channel simulations of others' states serve facilitative functions similar to more strict imitations of observed expressive behavior, suggesting flexibility in the motoric and affective systems involved in emotion processing and interpersonal emotion transfer. We discuss implications for embodiment research and the social consequences of expressing and matching emotions across nonverbal channels.     

Maternal Criticism and Adolescent Depressive and Generalized Anxiety Disorder Symptoms: A 6-Year Longitudinal Community Study

This 6-year longitudinal study examined the direction of effects (i.e., parent effects, child effects, or reciprocal effects) between maternal criticism and adolescent depressive and Generalized Anxiety Disorder (GAD) symptoms, including adolescents’ perceptions of criticism as a potential mediator. Consistent with recent empirical findings on associations between parenting and adolescent internalizing symptoms, we hypothesized stronger child effects than parent effects. A community sample of 497 adolescents (M _age?=?13.03 at T₁, 57 % boys) reported annually on their depressive and GAD symptoms as well as their perceptions of parental criticism. Their mothers (M _age?=?44.41 at T₁) also reported annually on their own critical behavior toward their adolescent. As expected, cross-lagged panel models demonstrated stronger child effects (i.e., adolescent psychopathology predicting maternal criticism) than parent effects (i.e., maternal criticism predicting adolescent psychopathology) for both adolescent depressive and GAD symptoms, including adolescent perceived criticism as a significant mediator. Our results emphasize the importance of considering (1) potential bidirectional influences over time, contrary to a focus on parent effects on adolescent mental health, as well as (2) adolescent perceptions of parenting as an important potential mediator in associations between aspects of the parent-adolescent relationship and adolescent internalizing psychopathological symptoms.     

Personal and Social Facets of Job Identity: A Person-Centered Approach

Purpose

The purpose of this study was to examine ego-identity (Erikson, Psychol Issues 1:1–171, 1959; Identity, youth and crisis, Norton, New York, 1968; Marcia, J Pers Soc Psychol 3:551–558, 1966) and social identity (Tajfel and Turner, In: Austin WG, Worchel S (Eds.) The social psychology of intergroup relations. Brooks/Cole, Monterey, pp 33–47 1979; Turner et al., Rediscovering the social group: A self-categorization theory. Blackwell, Oxford, 1987) theories within the organizational literature. We adopted a person-centered approach to analyze whether employees classified in various identity statuses and identification profiles exhibited differences in job outcomes (i.e., burnout, job satisfaction, and organizational citizenship behaviors). We also analyzed interconnections among identity statuses and identification profiles.

Design/methodology/approach

Participants were 515 employees (85.4 % women) between 24 and 64 years old. They completed self-reported questionnaires assessing personal identity, social identity, and job outcomes.

Findings

Cluster analysis indicated that participants could be classified into four identity statuses (i.e., achievement, early closure, moratorium, and searching moratorium) and into four identification profiles (i.e., orthogonal combinations of high vs. low organizational and group identification, respectively). Employees classified in the various identity statuses and identification profiles reported meaningful differences on job outcomes. Further, findings highlighted significant associations between identity statuses and identification profiles, giving rise to various identity configurations associated with job outcomes.

Implications

This study highlights the importance of integrating different facets of job identity. These findings have relevant implications in terms of suggesting which dimensions of identity should be promoted in order to reduce workers’ burnout, and enhance their satisfaction and organizational citizenship behaviors.

Originality/value

This study provides evidence for integrating ego-identity and social identity theories. In doing so, it bridges developmental psychology literature on personal identity with social and organizational psychology literature on social identity, setting the basis for a comprehensive line of research.     

Post-training intrahippocampal inhibition of class I histone deacetylases enhances long-term object-location memory

Long-term memory formation involves covalent modification of the histone proteins that package DNA. Reducing histone acetylation by mutating histone acetyltransferases impairs long-term memory, and enhancing histone acetylation by inhibiting histone deacetylases (HDACs) improves long-term memory. Previous studies using HDAC inhibitors to enhance long-term memory have focused on the fear-conditioning task using broad-spectrum HDAC inhibitors. We have found that post-training intrahippocampal administration of the broad-spectrum HDAC inhibitor trichostatin A (TSA) or the class I HDAC-selective inhibitor MS275 enhances long-term object-location memory, supporting a role for class I HDACs in the enhancement of hippocampus-dependent memory induced by HDAC inhibition.     

Personality Development from Age 12 to 25 and its Links with Life Transitions

During adolescence and young adulthood, individuals show personality changes and experience various life transitions. Whereas personality might affect the timing of life transitions, life transitions might also induce personality maturation. We examined Big Five personality maturation from age 12 to 25 using a 9-year longitudinal study of Dutch youths from two cohorts (n₁ = 683, M_ageT1 = 12.70; n₂ = 268, M_age T1 = 16.87). We linked personality maturation to the incidence and timing of four transitions: first romantic relationship, leaving the parental home, first job, and first cohabitation or marriage. Results indicated increases in mean levels, rank-order stabilities and profile stability of personality between age 12 and 25, which were largely replicated across the cohorts. Very few associations between personality and life transitions existed. However, higher mean-level Extraversion predicted leaving the parental home and starting the first romantic relationship, an earlier age when starting the first job, and an earlier average timing of transitions. Regarding social investment effects, we only found that those who never experienced a romantic relationship at age 25 decreased, while those who did increased in profile stability over time. These results suggest that personality consistently matures during adolescence and young adulthood and that higher Extraversion predict greater readiness for new steps towards adulthood.