Human movement-related brain potentials preceding voluntary movements in different arousal states monitored with skin potential level

The present study investigated the readiness potential (RP) preceding a brisk extension of the right middle finger during different arousal states as monitored by skin potential level (SPL). The late component of the readiness potential in the medium arousal state was significantly larger than those in the low and high arousal states. This finding indicates that the RP waveform may vary as a function of arousal states, suggesting the inverse U-shaped relationship proposed in studies of the contingent negative variation.     

Sequential learning and rule abstraction in Bengalese finches

The Bengalese finch (Lonchura striata var. domestica) is a species of songbird. Males sing courtship songs with complex note-to-note transition rules, while females discriminate these songs when choosing their mate. The present study uses serial reaction time (RT) to examine the characteristics of the Bengalese finches’ sequential behaviours beyond song production. The birds were trained to produce the sequence with an “A–B–A” structure. After the RT to each key position was determined to be stable, we tested the acquisition of the trained sequential response by presenting novel and random three-term sequences (random test). We also examined whether they could abstract the embedded rule in the trained sequence and apply it to the novel test sequence (abstract test). Additionally, we examined rule abstraction through example training by increasing the number of examples in baseline training from 1 to 5. When considered as (gender) groups, training with 5 examples resulted in no statistically significant differences in the abstract tests, while statistically significant differences were observed in the random tests, suggesting that the male birds learned the trained sequences and transferred the abstract structure they had learned during the training trials. Individual data indicated that males, as opposed to females, were likely to learn the motor pattern of the sequence. The results are consistent with observations that males learn to produce songs with complex sequential rules, whereas females do not.     

Personality Dysfunction and the Management of Chronic Medical Illness: A Community Health Sample

The purpose of this study was to determine the influence of personality disorders on perceived health status, self-efficacy for management of the chronic illness, and physician perception of patient health. A total of 607 patients with self-identified chronicillness(es) volunteered to participate in the study. Out of this sample, 147 had collaborative physician data indicating a chronic illness. The final sample was 143 due to incomplete data. Results suggested that maladaptive personality characteristics, as measured by the Short-Form of the Coolidge Axis II Inventory (SCATI), were related to a number of important factors that influence self-management of chronic illnesses. When the personality constellations were broken into 3 groups (normal, subclinical, and clinical) significant differences were found on the 3 groups of dependent variables (Subjective Health, Self-Efficacy, Physician Appraisal) for the different personality disorders. These data provide useful information on several factors that influence effective disease management. Clinical implications and directions for future research are provided.     

Personality Disorders in Older Adult Inpatients with Chronic Mental Illness

It has been hypothesized that some types of personality disorders tend to remit with age whereas others may become more prominent. The present study determined the prevalence and nature of 13 personality disorders with a self-report inventory (Coolidge Axis II Inventory) in an older group of chronically mentally ill inpatients (N = 30, mean age = 63 years) and a younger group of similar patients (N = 30, mean age = 39 years). All patients met DSM-IV criteria for either Schizophrenia, Schizoaffective Disorder, Bipolar Disorder, or recurrent severe Major Depression with psychotic features. The prevalence rate of personality disorders was high for both groups: 58% for the older sample and 66% for the younger group. The younger group was more likely to be diagnosed Antisocial, Borderline, Passive-Aggressive, Sadistic, and Schizotypal, but the groups were not different in the rates of Obsessive-Compulsive Disorder. This study supports the hypothesis that some personality disorders remit with age. However, no evidence was found to suggest that other personality disorders become more prominent in older adult psychiatric populations. Suggestions for future research are offered.     

Modulation of physical understanding by common marmosets (<Emphasis Type="Italic">Callithrix jacchus</Emphasis>)

The understanding of physical causality in common marmosets was tested using support problems in which a pair of sheets was presented to determine whether subjects would choose the sheet that had a food item on it (i.e., the sheet was supporting the food item). In two experiments, the conditions were manipulated in terms of the length of the sheet, the distance between the sheet and the food item, the presence of a gap separating the two sheets, and the size of the food item. In Experiment 1, the marmosets had difficulty rejecting an irretrievable food item when it was located closer to them than a retrievable item. Although their performance was strongly affected by the size of the irretrievable food item, they quickly learned to reject that alternative. In contrast, no improvement was found when one sheet was divided into two pieces such that the food item could not be retrieved when its near side was pulled. A similar response tendency was observed in Experiment 2, in which the effects of the large food item were examined in three different conditions. Thus, common marmosets were influenced by the perceptual features of the food in solving the support problems, as are other non-human primates. In addition, they consistently failed to appreciate the presence of a gap and, therefore, failed to reject the distracter alternative. However, all animals rapidly learned that the size of the food item was an irrelevant variable, and some showed an elementary conceptual understanding of support. These findings suggest that marmosets’ physical understanding may improve with experience.     

Insufficient augmentation of ambient GABA responsible for age-related cognitive deficit

Age-related degeneration of intracortical inhibition could underlie declines in cognitive function during senescence. Based on a hypothesis that a decrease in basal concentration of ambient (extrasynaptic) GABA with aging leads to depressing intracortical inhibition, we investigated how the basal concentration affects stimulus-evoked activity (as signal), ongoing-spontaneous activity (as noise) of neurons and their (signal-to-noise) ratio S/N. We simulated a neural network model equipped with a GABA transport system that regulates ambient GABA concentration in a neuronal activity-dependent manner. An increase in basal concentration augmented ambient GABA, increased GABA-mediated inhibitory current, and depressed ongoing-spontaneous activity while still keeping stimulus-evoked activity. This led to S/N improvement, for which it was necessary for the reversal potential of GABA transporter to be close to the resting potential of neurons. Above the resting potential, ongoing-spontaneous activity was predominantly enhanced due to excessive GABA-uptake from the extracellular space by transporters. Below the resting potential, stimulus-evoked activity was predominantly depressed, caused by excessive GABA-release. We suggest that the insufficient augmentation of ambient GABA due to a decrease in its basal concentration may be one of the possible causes of cognitive deficit with aging, increasing ongoing-spontaneous neuronal activity as noise. GABA transporter may contribute to improving S/N, provided that its reversal potential is close to the resting potential.     

On the relationship between Karen Horney's tripartite neurotic type theory and personality disorder features

[Horney, 1945] and [Horney, 1950] interpersonal theory [Horney, K. (1945). Our inner conflicts. New York, NY: W. W. Norton & Co., Inc.; Horney, K. (1950). Neurosis and human growth. New York, NY: W. W. Norton & Co., Inc.] postulated that individuals could move toward, move against, and move away from others as manifestations of their character development. In the present studies, it was hypothesized that Horney's tripartite theory might be useful in the elucidation of Diagnostic and Statistical Manual of Mental Disorders personality disorder features. In the first study, college students (n=198) completed the Coolidge Axis II Inventory [CATI; Coolidge, F. L. (1999), Coolidge Assessment Battery Manual. Port Huron, MI: Sigma Assessment Systems and Coolidge, F. L., & Merwin, M. M. (1992). Reliability and viability of the Coolidge Axis II Inventory: a new inventory for the assessment of personality disorders. Journal of Personality Assessment, 59, 223–238] and Cohen's 1967 35-item test [Cohen, J. B. (1967). An interpersonal orientation to the study of consumer behaviour. Journal of Marketing Research, 4, 270–278] of Horney's three types: Compliant, Aggressive, and Detached. In the second study, another group of college students (n=881) completed the CATI and Coolidge's 57-item test of Horney's three types. Results showed that both scales were reliable, generally similar, and numerous predicted correlational relationships were found. The usefulness of Horney's constructs in the understanding of personality disorders was discussed.     

Development of the overt-covert aggression inventory

The expression of anger in Japanese people is different from that of other races. We developed a new brief inventory, the Overt-Covert Aggression Inventory, to assess aggressive behavior ofJapanese people by focusing on their uniqueness and examined its reliability and validity. This inventory, the Center for Epidemiological Studies Depression scale, the Japanese version of the Buss-Perry Aggression Questionnaire, and the Picture-Frustration Study were administered to 3,104 men and 316 women in a factory. Internal consistency, test-retest reliability, concurrent validity, and construct validity of the scale were examined. We confirmed that the Overt-Covert Aggression Inventory has adequate reliability and sufficient concurrent validity, however, further studies of the construct validity and discriminant validity are required.     

Studies on the balancing,the minimal balancing,and the minimum balancing processes for social groups with planar and nonplanar graph structures

Balancing processes of social groups which transform an unbalanced group to a balanced one by changing the interpersonal relations in the group are characterized in terms of signed graphs. The graphs are given by categorizing the (interpersonal) relations within groups as positive or negative. A balanced state of a group is defined as one in which all the circuits of the graph have a positive sign, and the other cases are called unbalanced states. First, we show that a balancing process for a signed graph (changing the signs of its lines) is decomposed into that for each of the block components of the graph. Second, we classify signed graphs as planar and nonplanar. For the planar cases, we define the dual graph of a planar signed graph, and the balancing processes are characterized by specified sets of lines of the graph. According to the characterization, effective algorithms to derive the minimal and the minimum balancing processes are proposed. For the nonplanar cases, the balancing processes are characterized in terms of adjacency matrices of nonplanar signed graphs by introducing the notion of sign vectors. The characterization results in effective algorithms to derive the minimal and the minimum balancing processes. These discussions are also extended to the case where interpersonal relations have their own directions.