The complementary brain: unifying brain dynamics and modularity

How are our brains functionally organized to achieve adaptive behavior in a changing world? This article presents one alternative to the computer analogy that suggests brains are organized into independent modules. Evidence is reviewed that brains are in fact organized into parallel processing streams with complementary properties. Hierarchical interactions within each stream and parallel interactions between streams create coherent behavioral representations that overcome the complementary deficiencies of each stream and support unitary conscious experiences. This perspective suggests how brain design reflects the organization of the physical world with which brains interact. Examples from perception, learning, cognition and action are described, and theoretical concepts and mechanisms by which complementarity might be accomplished are presented.     

Sentence reading: do we make use of orthographic cues in homophones?

Starting from the finding that currently phonological models of visual word processing predominate, we examined what happened when important morphological information is disclosed in the orthography but not in the phonology. To do so, we made use of a peculiarity in Dutch. In this language, some forms of the present and the past tense of verbs are homophones or homographs. This allowed us to look at the power of orthographic and phonological cues to derive the tense of the verb. Two experiments showed that orthographic cues alone suffice to recover the tense of the verb, and that this recovery does not take more time than tense recovery on the basis of a combination of orthographic and phonological cues. On the basis of these results, we conclude that orthographic cues in homophones are very efficient during silent reading. Our findings, however, do not allow us to conclude whether this is due to a direct route from orthography to meaning, or to a specialised, morpho-syntactic back-up strategy elicited by certain sequences of letters.     

Responses to nervous breakdowns in America over a 40-year period. Mental health policy implications

The 1957 and 1976 Americans View Their Mental Health surveys from the Institute of Social Research were partially replicated in the 1996 General Social Survey (GSS) to examine the policy implications of people's responses to feeling an impending nervous breakdown. Questions about problems in modern living were added to the GSS to provide a profile of the public's view of mental health problems. Results were compared for 1957, 1976, and 1996. In 1957, 19% of respondents had experienced an impending nervous breakdown; in 1996, 26% had had this experience. Between 1957 and 1996, participants increased their use of informal social supports, decreased their use of physicians, and increased their use of nonmedical mental health professionals. These findings support policies that strengthen informal support seeking and access to effective psychosocial treatments rather than current mental health reimbursement practices, which emphasize the role of primary care physicians.     

Responsibility attitudes and interpretations are characteristic of obsessive compulsive disorder

The cognitive-behavioural theory of Obsessive Compulsive Disorder (OCD) proposes that a key factor influencing obsessional behaviour is the way in which the intrusive cognitions are interpreted. The present paper reports an investigation of links between clinical symptoms (of anxiety, depression and obsessionality) and responsibility beliefs. These beliefs include not only measures of general responsibility attitudes (assumptions) but also more specific responsibility appraisals consequent on intrusive cognitions. The characteristics of two new questionnaires specifically designed to measure these beliefs were assessed in patients suffering from Obsessive Compulsive Disorder, in patients suffering from other anxiety disorders and in non-clinical controls. The scales measuring negative beliefs about responsibility were found to have good reliability and internal consistency. Comparisons between criterion groups indicate considerable specificity for both assumptions and appraisals with respect to OCD. There was also good evidence of specificity in the association between responsibility cognitions and obsessional symptoms across groups, and that this association was not a consequence of links with anxiety or depressive symptoms. Although the two measures were correlated, they each made unique contributions to the prediction of obsessional symptoms. Overall, the results are consistent with the hypothesis that responsibility beliefs are important in the experience of obsessional problems.     

Predicting who suffers psychological trauma in the first year after a road accident

This study followed up a cohort (n = 72) of consecutive road accident attendees to hospital for one year, assessing them soon after the accident and 3, 6 and 12 months later with the General Health Questionnaire (28-item version); Impact of Event Scale and Posttraumatic Stress Disorder Interview. The aim of the study was to identify demographic, accident and subjective reality variables that could predict who was likely to suffer psychological disorder in the future. The extent of injury was a particular focus for the study. Results showed that at different time periods, using stepwise, multiple regression analyses, between 12 and 77% of variance in trauma measures could be predicted. Severity of injury was a stronger predictor longer after the accident.     

Paradoxical breathlessness in asthma

This study tested the hypothesis that breathlessness in asthma relates linearly to airway obstruction when situational, attentional and emotional influences are held constant via random presentation of different intensities of externally applied airflow obstruction. Adolescents with stable asthma and normal controls (n=25+25) with lung functions of approximately 3.5 l forced expiratory volume in 1 s (FEV₁) breathed through a device which obstructed airflow with five stimulus intensities, analogous to a mean reduction in FEV₁ of 8–66%. A session consisted of 10 blocks, each with presentation of five stimulus intensities plus the baseline resistance of the apparatus. Breathlessness was continuously reported by moving a lever along a 10-point scale. The mean breathlessness was computed per stimulus intensity. Lung function and anxiety were measured before and after the test.

Participants with asthma, not controls, manifested a paradoxical response: they reported significantly more breathlessness, but undifferentially. One patient against 12 controls reported consistently more breathlessness from baseline to severe obstruction. The hypothesis was only supported for controls. Breathlessness did not correlate with severity of asthma, lung function, duration of asthma, number of exacerbations over the last six months, age, sex or anxiety.

It was concluded that the meaning of airflow obstruction in patients with asthma has changed and underlies their paradoxical responses, even when situational, attentional and emotional factors are controlled.     

Realism of confidence in obsessive-compulsive checkers

The study examined whether obsessive-compulsive (OC) checkers have reduced confidence in their knowledge. OC checkers were compared with panic disorder (PD) patients and nonpatient controls using a calibration-of-knowledge procedure. Participants completed a general knowledge questionnaire, rated their confidence in each answer, and estimated the total number of correct answers. These responses were converted to 2 measures of confidence relative to performance--over/underconfidence and over/underestimation. OC checkers had lower scores than nonpatients did on both measures, whereas the PD patients did not differ from either group. For the OC checkers, relative confidence was inversely related to the severity of obsessions. The authors speculate that confidence may depend on a confirmation bias in testing hypotheses and that the reduced confidence in OC checkers may reflect a disconfirmation bias in this population.     

Where's the ball? Two- and three-year-olds reason about unseen events

Children 2, 2 1/2, and 3 years of age engaged in a search task in which they opened 1 of 4 doors in an occluder to retrieve a ball that had been rolled behind the occluder. The correct door was determined by a partially visible wall placed behind the occluder that stopped the motion of the unseen ball. Only the oldest group of children was able to reliably choose the correct door. All children were able to retrieve a toy that had been hidden in the same apparatus if the toy was hidden from the front by opening a door. Analysis of the younger children's errors indicated that they did not search randomly but instead used a variety of strategies. The results are consistent with the Piagetian view that the ability to use representations to guide action develops slowly over the first years of life.