Similarities and distinctions among current models of prefrontal cortical functions

Review of EEG Affective Recognition with a Neuroscience Perspective

Emotions are a series of subconscious, fleeting, and sometimes elusive manifestations of the human innate system. They play crucial roles in everyday life-influencing the way we evaluate ourselves, our surroundings, and how we interact with our world. To date, there has been an abundance of research on the domains of neuroscience and affective computing, with experimental evidence and neural network models, respectively, to elucidate the neural circuitry involved in and neural correlates for emotion recognition. Recent advances in affective computing neural network models often relate closely to evidence and perspectives gathered from neuroscience to explain the models. Specifically, there has been growing interest in the area of EEG-based emotion recognition to adopt models based on the neural underpinnings of the processing, generation, and subsequent collection of EEG data. In this respect, our review focuses on providing neuroscientific evidence and perspectives to discuss how emotions potentially come forth as the product of neural activities occurring at the level of subcortical structures within the brain's emotional circuitry and the association with current affective computing models in recognizing emotions. Furthermore, we discuss whether such biologically inspired modeling is the solution to advance the field in EEG-based emotion recognition and beyond.

Event Perception and Social Skills in Undergraduates with ADHD Symptoms

BACKGROUND

Event perception provides a promising, novel approach for investigating underlying cognitive mechanisms of the social impairment associated with symptoms of ADHD.

AIMS

The goal of this study was to establish the relationship among event perception, symptoms of ADHD, and social skills.

METHODOLOGY

Eighty-three undergraduates were recruited from the University of Ottawa first year psychology courses (38 with ADHD, 45 without ADHD). They performed an event perception task and completed self-report questionnaires assessing social functioning and symptoms of ADHD (The Social Skills-Improvement System and the Conner's CBRS-SR).

RESULTS

Bootstrapping mediation analyses revealed that symptoms of inattention and hyperactivity mediated the relationship between event perception and social skills. A model with predictor and mediator reversed was also tested, and was not significant, providing strength to the directionality of the relationships. Results highlight the applicability of event perception to understanding the association between social impairment and symptoms of ADHD.

The neuroscience of advanced scientific concepts

Cognitive neuroscience methods can identify the fMRI-measured neural representation of familiar individual concepts, such as apple, and decompose them into meaningful neural and semantic components. This approach was applied here to determine the neural representations and underlying dimensions of representation of far more abstract physics concepts related to matter and energy, such as fermion and dark matter, in the brains of 10 Carnegie Mellon physics faculty members who thought about the main properties of each of the concepts. One novel dimension coded the measurability vs. immeasurability of a concept. Another novel dimension of representation evoked particularly by post-classical concepts was associated with four types of cognitive processes, each linked to particular brain regions: (1) Reasoning about intangibles, taking into account their separation from direct experience and observability; (2) Assessing consilience with other, firmer knowledge; (3) Causal reasoning about relations that are not apparent or observable; and (4) Knowledge management of a large knowledge organization consisting of a multi-level structure of other concepts. Two other underlying dimensions, previously found in physics students, periodicity, and mathematical formulation, were also present in this faculty sample. The data were analyzed using factor analysis of stably responding voxels, a Gaussian-naïve Bayes machine-learning classification of the activation patterns associated with each concept, and a regression model that predicted activation patterns associated with each concept based on independent ratings of the dimensions of the concepts. The findings indicate that the human brain systematically organizes novel scientific concepts in terms of new dimensions of neural representation.

The role of the mPFC in the social influence of majority and expert opinion

Individual attitudes and preferences are easily affected by social information. In a world where information sharing and dissemination are extremely convenient, social influence has played a greater role than in any previous era. Previous studies have suggested that the medial prefrontal cortex (mPFC) participates in mediating the tendency towards social conformity. However, the specific role of this brain area is still unknown, and it is not clear whether various types of external information influences share a mechanism. In this research, we aimed to use transcranial direct current stimulation (tDCS) to further explore the role of the mPFC in human conformity behaviour. In our experiment, the subjects received the majority opinion/expert opinion, and conformity behaviour was measured by the subject's tendency to follow this information after receiving the social information. Our research found that when social information conveys the majority opinion, cathodal stimulation of the mPFC significantly enhances the subject's consistency tendency. When social information conveys an expert opinion, stimulation of the mPFC has no significant effect on the conformity tendency of subjects. The results suggest that the mPFC plays an inhibitory role in regulating the social conformity tendency and that the activated neural circuits may vary with source when dealing with social influences.

Deficient semantic knowledge of the life course-Examining the cultural life script in Alzheimer's disease

Cultural life scripts are culturally transmitted semantic knowledge of the expected order and timing of major transitional events in a prototypical life course. This cognitive schema has been shown to serve as an important mnemonic template that guides retrieval from autobiographical memory, especially for positive and important life events. Autobiographical memory deficits are one of the earliest and most prominent symptoms in Alzheimer's disease (AD). However, no studies have examined cultural life scripts in patients with AD, despite semantic memory impairments being reported even in the early stages of the disease. The aim of the present work was to assess life-script knowledge in older adults diagnosed with AD, particularly in terms of knowledge for the content of life-script events and the timing and temporal order of these events. Twenty-one older adults diagnosed with AD and 22 healthy age-matched controls completed the standard life-script task (Berntsen & Rubin, 2004, Memory & Cognition, 32[3], 427-442). We found that while AD patients produced significantly fewer life-script events, the content of the generated events were quite consistent with those of the controls and the cultural norms. AD patients were particular impaired with regard to the normative timing and order of life-script events, suggesting that these components of the cultural life script are more vulnerable to cognitive decline. The findings are discussed in relation to impaired script knowledge and semantic memory deficits in AD.

Event Segmentation Deficits in ADHD

Event segmentation is the automatic cognitive process of chunking ongoing information into meaningful events. Event segmentation theory (EST) proposes that event segmentation is a grouping process fundamental to normal, everyday perceptual processing, taking a central role in attention and action control. The neurocognitive deficits observed among individuals with ADHD overlap those involved in event segmentation, but to date no research has examined event segmentation in the context of ADHD. Objective: The goal of this study was to document the event segmentation deficits of individuals with ADHD. Method: Seventy-five undergraduates with ADHD and seventy-nine without ADHD performed an event segmentation task. Results: Results revealed that undergraduates with ADHD identify significantly more large events. Conclusion: These findingssuggest explicit disturbances in the event model and updating system among those with ADHD. Future research directions include further elucidating these deficits with more varied stimuli and establishing associations with functional impairments.

A Representational Approach to Executive Function Impairments in Young Adults with Down Syndrome

Based on a representational perspective, this paper examines executive functioning in Down syndrome. Sixteen young adults with Down syndrome, 16 mental age- and 16 age-matched controls were compared on script sequencing and sorting tasks. Participants were asked to reestablish the sequential structure of script actions given with or without irrelevant actions. Impairments in script information processing were observed only in young adults with Down syndrome, who performed more slowly than controls, making mistakes in ordering actions, but rejecting aberrant elements. These data are consistent with the view that Down syndrome impairs the syntactic but not semantic dimension of script representation.

Does transcranial direct current stimulation to the prefrontal cortex affect social behavior? A meta-analysis

This meta-analysis (k = 48, N = 2196) examined the effect of transcranial direct current brain stimulation (tDCS) applied to the prefrontal cortex on a variety of social behaviors, including aggression, overeating, impulsivity, bias, honesty, and risk-taking. tDCS showed an overall significant effect on reducing undesirable behaviors, with an average effect size of d = −0.20. tDCS was most effective at reducing risk-taking behavior, bias, and overeating. tDCS did not affect aggression, impulsivity, or dishonesty. We examined moderators such as brain region of interest, online vs offline stimulation, within- vs between-subjects designs, dose, and duration, but none showed significant interactions. We also tested for potential publication bias using two different tools, which indicated signs of publication bias in the literature. After correcting for potential publication bias, the effect of tDCS was still significant, but the size was reduced (d = −0.10). These findings suggest the presence of tDCS studies with null findings outside of the published literature. Taken together, these results suggest that although tDCS can reduce undesirable behaviors, researchers should consider the types of behaviors they measure and use strategies to ensure sufficient power to detect a possible effect of tDCS on social behavior.

Praising others differently: neuroanatomical correlates to individual differences in trait gratitude and elevation

Differing from basic emotions such as happiness, gratitude and elevation are important other-praising emotions. Previous behavioral studies have established that these complex emotions differ from each other; however, it remains under-investigated whether proneness to these emotions have common or distinct neuroanatomical correlates. Here we used voxel-based morphometry to identify the common and distinct neuroanatomical correlates of trait (i.e. proneness to) gratitude and elevation. We used the Gratitude Questionnaire-6 and the trait elevation scale to measure these affective traits. We demonstrated that trait gratitude was positively correlated with gray matter volume (GMV) in the left cerebellum extending to fusiform gyrus, and also the right middle occipital gyrus (MOG) extending to posterior superior temporal sulcus (pSTS) and temporoparietal junction (TPJ), while trait elevation was negatively correlated with GMV in the left dorsolateral prefrontal cortex. While controlling each other, all the regions still held significant, except the right MOG and pSTS/TPJ. The results indicate that there are distinct neuroanatomical correlates for proneness to gratitude and elevation, while the evidence is mixed that pSTS/TPJ may be the common correlates for them. The implications of these findings are discussed.

Dual route for subtask order control: Evidence from the psychological refractory paradigm

A change in subtask order in the psychological refractory period (PRP) paradigm increases the effect of stimulus onset asynchrony (SOA) on the second response. We used a paradigm with cued, randomly determined subtask order to test the hypothesis that this SOA by order switch overadditivity reflects order control, via “copying” stimulus order. In Experiments 1a and 1b, overadditivity was evident only with insufficient opportunity for cue-based order control. In Experiment 2, overadditivity was decreased by using the same set of stimuli in the two subtasks, presumably by removing the opportunity to rely on stimulus order. In Experiment 3, removing the order cue increased the overadditivity, presumably because control was based solely upon copying stimulus order. The results indicate interactive top-down and bottom-up order control. Implications to theories of the PRP paradigm are discussed.

The Seduction Script: Psychological and Cultural Norms of Interpersonal Approaches As Markers for Sexual Aggression and Abuse

Hardly any subjects enjoy greater – public or private – interest than the art of flirtation and seduction. However, interpersonal approach behavior not only paves the way for sexual interaction and reproduction, but it simultaneously integrates non-sexual psychobiological and cultural standards regarding consensus and social norms. In the present paper, we use script theory, a concept that extends across psychological and cultural science, to assess behavioral options during interpersonal approaches. Specifically, we argue that approaches follow scripted event sequences that entail ambivalence as an essential communicative element. On the one hand, ambivalence may facilitate interpersonal approaches by maintaining and provoking situational uncertainty, so that the outcome of an action – even after several approaches and dates – remains ambiguous. On the other hand, ambivalence may increase the risk for sexual aggression or abuse, depending on the individual’s abilities, the circumstances, and the intentions of the interacting partners. Recognizing latent sequences of sexually aggressive behavior, in terms of their rigid structure and behavioral options, may thus enable individuals to use resources efficiently, avoid danger, and extricate themselves from assault situations. We conclude that interdisciplinary script knowledge about ambivalence as a core component of the seduction script may be helpful for counteracting subtly aggressive intentions and preventing sexual abuse. We discuss this with regard to the nature-nurture debate as well as phylogenetic and ontogenetic aspects of interpersonal approach behavior and its medial implementation.

Effects of penetrating traumatic brain injury on event segmentation and memory

Penetrating traumatic brain injury (pTBI) is associated with deficits in cognitive tasks including comprehension and memory, and also with impairments in tasks of daily living. In naturalistic settings, one important component of cognitive task performance is event segmentation, the ability to parse the ongoing stream of behavior into meaningful units. Event segmentation ability is associated with memory performance and with action control, but is not well assessed by standard neuropsychological assessments or laboratory tasks. Here, we measured event segmentation and memory in a sample of 123 male military veterans aged 59-81 who had suffered a traumatic brain injury as young men, and 34 demographically similar controls. Participants watched movies of everyday activities and segmented them to identify fine-grained or coarse-grained events, and then completed tests of recognition memory for pictures from the movies and of memory for the temporal order of actions in the movies. Lesion location and volume were assessed with computed tomography (CT) imaging. Patients with traumatic brain injury were impaired on event segmentation. Those with larger lesions had larger impairments for fine segmentation and also impairments for both memory measures. Further, the degree of memory impairment was statistically mediated by the degree of event segmentation impairment. There was some evidence that lesions to the ventromedial prefrontal cortex (vmPFC) selectively impaired coarse segmentation; however, lesions outside of a priori regions of interest also were associated with impaired segmentation. One possibility is that the effect of vmPFC damage reflects the role of prefrontal event knowledge representations in ongoing comprehension. These results suggest that assessment of naturalistic event comprehension can be a valuable component of cognitive assessment in cases of traumatic brain injury, and that interventions aimed at event segmentation could be clinically helpful.

Virtual reality and neuropsychological assessment: The reliability of a virtual kitchen to assess daily-life activities in victims of traumatic brain injury

Traumatic brain injury (TBI) causes impairments affecting instrumental activities of daily living (IADL). However, few studies have considered virtual reality as an ecologically valid tool for the assessment of IADL in patients who have sustained a TBI. The main objective of the present study was to examine the use of the Nonimmersive Virtual Coffee Task (NI-VCT) for IADL assessment in patients with TBI. We analyzed the performance of 19 adults suffering from TBI and 19 healthy controls (HCs) in the real and virtual tasks of making coffee with a coffee machine, as well as in global IQ and executive functions. Patients performed worse than HCs on both real and virtual tasks and on all tests of executive functions. Correlation analyses revealed that NI-VCT scores were related to scores on the real task. Moreover, regression analyses demonstrated that performance on NI-VCT matched real-task performance. Our results support the idea that the virtual kitchen is a valid tool for IADL assessment in patients who have sustained a TBI.

Exploring Temporal Progression of Events Using Eye Tracking

This study investigates the representation of the temporal progression of events by means of the causal change in a patient. Subjects were asked to verify the relationship between adjectives denoting a source and resulting feature of a patient. The features were presented either chronologically or inversely to a primed event context given by a verb (to cut: long-short vs. short-long). Effects on response time and on eye movement data show that the relationship between features presented chronologically is verified more easily than that between features presented inversely. Post hoc, however, we found that the effects of temporal order occurred only when subjects read the features more than once. Then, the relationship between the features is matched with the causal change implied by the event context (contextual strategy). When subjects read the features only once, subjects respond to the relationship between the features without taking into account the event context.

Decoding the Formation of New Semantics: MVPA Investigation of Rapid Neocortical Plasticity during Associative Encoding through Fast Mapping

Neocortical structures typically only support slow acquisition of declarative memory; however, learning through fast mapping may facilitate rapid learning-induced cortical plasticity and hippocampal-independent integration of novel associations into existing semantic networks. During fast mapping the meaning of new words and concepts is inferred, and durable novel associations are incidentally formed, a process thought to support early childhood's exuberant learning. The anterior temporal lobe, a cortical semantic memory hub, may critically support such learning. We investigated encoding of semantic associations through fast mapping using fMRI and multivoxel pattern analysis. Subsequent memory performance following fast mapping was more efficiently predicted using anterior temporal lobe than hippocampal voxels, while standard explicit encoding was best predicted by hippocampal activity. Searchlight algorithms revealed additional activity patterns that predicted successful fast mapping semantic learning located in lateral occipitotemporal and parietotemporal neocortex and ventrolateral prefrontal cortex. By contrast, successful explicit encoding could be classified by activity in medial and dorsolateral prefrontal and parahippocampal cortices. We propose that fast mapping promotes incidental rapid integration of new associations into existing neocortical semantic networks by activating related, nonoverlapping conceptual knowledge. In healthy adults, this is better captured by unique anterior and lateral temporal lobe activity patterns, while hippocampal involvement is less predictive of this kind of learning.

Semantic priming of progression features in events

Event knowledge includes persons and objects and their roles in the event. This study investigated whether the progression of patients from a source to a resulting feature, such as the progression of hair that is cut from long to short, forms part of event representations. Subjects were presented with an event prime followed by two adjectives and asked to judge whether the adjectives were interrelated. Results showed that the semantic interrelation of two adjectives is recognized faster and more accurately when the adjectives denote source and resulting features of the patient of the primed event ("cutting": long-short). Furthermore, we found that presenting an event-related adjective in combination with an unrelated adjective makes it more difficult to recognize that the two adjectives are not interrelated, but only when the event-related adjective denotes a source feature. We argue that an inference mechanism automatically completes the representation of the event. We conclude that source and resulting features are represented in a goal-directed and chronological way.

Diffusion tensor MR imaging of white matter integrity in HIV-positive patients with planning deficit

INTRODUCTION

The aim of this study was to evaluate whether normal controls and human immunodeficiency virus (HIV) patients with and without planning deficits differ on white matter integrity.

METHODS

A total of 34 HIV-positive patients with planning deficits were compared with 13 HIV-positive patients without planning deficits and 19 gender-, age-, and education-matched control subjects. Diffusion tensor imaging (DTI) was performed along 30 noncolinear directions in a 1.5-T scanner. For tract-based spatial statistics analysis, a white matter skeleton was created, and a permutation-based inference with 5000 permutations with a threshold of p < 0.05 was used to identify abnormalities in fractional anisotropy (FA). The median, radial, and axial diffusivities were also projected onto the mean FA skeleton.

RESULTS

Compared with controls, HIV-positive patients with planning deficits had decreased FA in bilateral anterior thalamic radiations, bilateral inferior fronto-occiptal fasciculi, genu and splenium of the corpus callosum, bilateral superior longitudinal fascicule, and bilateral uncinate fasciculi. Compared to HIV-positive patients without planning deficits, patients with planning deficits had decreased FA in bilateral anterior thalamic radiations, bilateral inferior fronto-occiptal fasciculi, genu of the corpus callosum, bilateral superior longitudinal fascicule, and right uncinate fascicule.

CONCLUSION

DTI can detect extensive white matter abnormalities in the normal-appearing white matter of HIV-positive patients with planning deficits compared with controls and HIV-positive patients without planning deficits.

Cytoarchitecture, probability maps and functions of the human frontal pole

The frontal pole has more expanded than any other part in the human brain as compared to our ancestors. It plays an important role for specifically human behavior and cognitive abilities, e.g. action selection (Kovach et al., 2012). Evidence about divergent functions of its medial and lateral part has been provided, both in the healthy brain and in psychiatric disorders. The anatomical correlates of such functional segregation, however, are still unknown due to a lack of stereotaxic, microstructural maps obtained in a representative sample of brains. Here we show that the human frontopolar cortex consists of two cytoarchitectonically and functionally distinct areas: lateral frontopolar area 1 (Fp1) and medial frontopolar area 2 (Fp2). Based on observer-independent mapping in serial, cell-body stained sections of 10 brains, three-dimensional, probabilistic maps of areas Fp1 and Fp2 were created. They show, for each position of the reference space, the probability with which each area was found in a particular voxel. Applying these maps as seed regions for a meta-analysis revealed that Fp1 and Fp2 differentially contribute to functional networks: Fp1 was involved in cognition, working memory and perception, whereas Fp2 was part of brain networks underlying affective processing and social cognition. The present study thus disclosed cortical correlates of a functional segregation of the human frontopolar cortex. The probabilistic maps provide a sound anatomical basis for interpreting neuroimaging data in the living human brain, and open new perspectives for analyzing structure-function relationships in the prefrontal cortex. The new data will also serve as a starting point for further comparative studies between human and non-human primate brains. This allows finding similarities and differences in the organizational principles of the frontal lobe during evolution as neurobiological basis for our behavior and cognitive abilities.

Multiple effects of β-amyloid on single excitatory synaptic connections in the PFC

Prefrontal cortex (PFC) is recognized as an AD-vulnerable region responsible for defects in cognitive functioning. Pyramidal cell (PC) connections are typically facilitating (F) or depressing (D) in PFC. Excitatory post-synaptic potentials (EPSPs) were recorded using patch-clamp from single connections in PFC slices of rats and ferrets in the presence of β-amyloid (Aβ). Synaptic transmission was significantly enhanced or reduced depending on their intrinsic type (facilitating or depressing), Aβ species (Aβ 40 or Aβ 42) and concentration (1-200 nM vs. 0.3-1 μ M). Nanomolar Aβ 40 and Aβ 42 had opposite effects on F-connections, resulting in fewer or increased EPSP failure rates, strengthening or weakening EPSPs and enhancing or inhibiting short-term potentiation [STP: synaptic augmentation (SA) and post-tetanic potentiation (PTP)], respectively. High Aβ 40 concentrations induced inhibition regardless of synaptic type. D-connections were inhibited regardless of Aβ species or concentration. The inhibition induced with bath application was hard to recover by washout, but a complete recovery was obtained with brief local application and prompt washout. Our data suggests that Aβ 40 acts on the prefrontal neuronal network by modulating facilitating and depressing synapses. At higher levels, both Aβ 40 and Aβ 42 inhibit synaptic activity and cause irreversible toxicity once diffusely accumulated in the synaptic environment.

Medial temporal lobe volume predicts elders' everyday memory

Deficits in memory for everyday activities are common complaints among healthy and demented older adults. The medial temporal lobes and dorsolateral prefrontal cortex are both affected by aging and early-stage Alzheimer's disease, and are known to influence performance on laboratory memory tasks. We investigated whether the volume of these structures predicts everyday memory. Cognitively healthy older adults and older adults with mild Alzheimer's-type dementia watched movies of everyday activities and completed memory tests on the activities. Structural MRI was used to measure brain volume. Medial temporal but not prefrontal volume strongly predicted subsequent memory. Everyday memory depends on segmenting activity into discrete events during perception, and medial temporal volume partially accounted for the relationship between performance on the memory tests and performance on an event-segmentation task. The everyday-memory measures used in this study involve retrieval of episodic and semantic information as well as working memory updating. Thus, the current findings suggest that during perception, the medial temporal lobes support the construction of event representations that determine subsequent memory.

The hierarchical and functional connectivity of higher-order cognitive mechanisms: neurorobotic model to investigate the stability and flexibility of working memory

Higher-order cognitive mechanisms (HOCM), such as planning, cognitive branching, switching, etc., are known to be the outcomes of a unique neural organizations and dynamics between various regions of the frontal lobe. Although some recent anatomical and neuroimaging studies have shed light on the architecture underlying the formation of such mechanisms, the neural dynamics and the pathways in and between the frontal lobe to form and/or to tune the stability level of its working memory remain controversial. A model to clarify this aspect is therefore required. In this study, we propose a simple neurocomputational model that suggests the basic concept of how HOCM, including the cognitive branching and switching in particular, may mechanistically emerge from time-based neural interactions. The proposed model is constructed such that its functional and structural hierarchy mimics, to a certain degree, the biological hierarchy that is believed to exist between local regions in the frontal lobe. Thus, the hierarchy is attained not only by the force of the layout architecture of the neural connections but also through distinct types of neurons, each with different time properties. To validate the model, cognitive branching and switching tasks were simulated in a physical humanoid robot driven by the model. Results reveal that separation between the lower and the higher-level neurons in such a model is an essential factor to form an appropriate working memory to handle cognitive branching and switching. The analyses of the obtained result also illustrates that the breadth of this separation is important to determine the characteristics of the resulting memory, either static memory or dynamic memory. This work can be considered as a joint research between synthetic and empirical studies, which can open an alternative research area for better understanding of brain mechanisms.

The impact of semantic dementia on everyday actions: evidence from an ecological study

In theory, semantic memory may trigger and support the execution of everyday activities. This study explored this question by comparing three patients with semantic dementia to 40 normal controls performing different everyday activities. Participants were tested in their home using the Instrumental Activities of Daily Living Profile, an ecological measure of everyday functioning. Participants were informed that they had unknowingly invited two guests for lunch and should prepare accordingly. With these instructions, they dress to go outdoors, go to the grocery store, shop for food, prepare a hot meal, have the meal with the guests, and clean up after the meal. Performance was analyzed on the basis of four operations related to problem solving: formulate a goal, plan, execute, and verify attainment of the goal. Results indicate that compared to normal controls, two patients had significant difficulties and needed assistance with all operations of problem-solving, particularly while preparing a meal and cleaning up after the meal. One patient showed no difficulties despite severe semantic deficits. These results suggest that semantic deficits alone cannot explain the difficulties observed, but may contribute to some aspects of everyday actions such as those involved in everyday problem-solving.

Role of the right prefrontal cortex in ill-structured planning

We tested an architect with a lesion to the right prefrontal cortex in a real-world architectural design/planning task that required him to develop a new design for our lab space and compared his performance to an age- and education-matched architect. The patient understood the task and even observed that "this is a very simple problem." His sophisticated architectural knowledge base was still intact and he used it quite skilfully during the problem structuring phase. However, the patient's problem-solving behaviour differed from the control's behaviour in the following ways: (1) he was unable to make the transition from problem structuring to problem solving; (2) as a result preliminary design did not start until two thirds of the way into the session; (3) the preliminary design phase was minimal and erratic, consisting of three independently generated fragments; (4) there was no progression or lateral development of these fragments; (5) there was no carry-over of abstract information into the preliminary design or later phases, and (6) the patient did not make it to the detailing phase. This suggests that the key to understanding our patient's deficit is to understand the cognitive processes and mechanisms involved in the preliminary design phase. We appeal to a theory of design problem solving (Goel, 1995) that associates cognitive processes involved in preliminary design with "lateral" state transformations and argues that "ill-structured" representational and computational systems are necessary to support these transformations. We conclude that the neural basis of this system is selectively damaged in our patient.

Organizational Structure Reduces Processing Load in the Prefrontal Cortex During Discourse Processing of Written Text: Implications for High-Level Reading Issues After TBI

Adults with traumatic brain injury (TBI) can demonstrate marked difficulty producing discourse during story retell and story generation tasks. Changes in discourse production have been detailed in terms of fewer content units and infrequent use of story grammar elements essential for organization. One implication is that poor use of story grammar elements during discourse production may signal reduced ability to utilize these elements in other communication realms (e.g., reading comprehension). The neural architecture that supports discourse organization, primarily the medial prefrontal cortex, is particularly susceptible to damage secondary to acquired brain injury. In this event related functional magnetic resonance imaging (fMRI) study, we describe cortical activation patterns of unimpaired readers as they are presented with discourse that is varied in terms of structural organization. The results suggest reading discourse with less structure is associated with increased cortical activity (e.g., higher processing demands) as compared to reading discourse with more traditional structural cues (e.g., story grammar). We discuss cortical areas implicated and potential implications for supporting discourse communication in persons following TBI.

Context-sensitive Cognitive Rehabilitation after Brain Injury: Theory and Practice

The goal of this article is to describe and offer a rationale for an approach to cognitive rehabilitation labelled “context sensitive”. This approach stands in contrast to the modern tradition of cognitive rehabilitation that features massed and decontextualized process-specific cognitive exercises. The paper begins with theoretical considerations, emphasises the history of research in transfer of cognitive skill, incorporates the World Health Organization framework, describes context-sensitive apprenticeship procedures, draws on evidence accumulated over several decades with related disability groups, and ends with answers to frequently asked questions.

Reconstruction of Identity After Brain Injury

Following severe traumatic brain injury, difficulty with behavioural adjustment and community reintegration is common. A potential contributor to this difficulty is a sense of personal identity that is inconsistent with the restrictions on activity and need for effortful compensation imposed by persistent impairment. We summarise an information processing framework within which the impact of schematic mental models of self is explained and present intervention procedures designed to help individuals with traumatic brain injury reconstruct an organised and positive sense of personal identity. We conclude the paper with three instructive case illustrations.

Social cognition, executive functioning, and neuroimaging correlates of empathic deficits in frontotemporal dementia

The authors investigated aspects of interpersonal sensitivity and perspective-taking in relation to empathy, social cognitions, and executive functioning in 26 frontotemporal dementia (FTD) patients. Behavioral-variant FTD (bvFTD) patients were significantly impaired on caregiver assessments of empathy, although self-ratings were normal. Progressive nonfluent aphasia and semantic-dementia samples were rarely abnormal. In bvFTD, empathy ratings were found to be correlated with social cognition and executive functioning measures, but not depression. Voxel-based morphometry revealed that reduced empathic perspective-taking was related to bifrontal and left anterior temporal atrophy, whereas empathic emotions were related to right medial frontal atrophy. Findings suggest that bvFTD causes multiple types of breakdown in empathy, social cognition, and executive resources, mediated by frontal and temporal disease.

Script generation of activities of daily living in HIV-associated neurocognitive disorders

Script generation describes one's ability to produce complex, sequential action plans derived from mental representations of everyday activities. The aim of this study was to assess the effect of human immunodeficiency virus (HIV) infection on script generation performance. Sixty HIV+ individuals (48% of whom had HIV-associated neurocognitive disorders [HAND]) and 26 demographically comparable HIV- participants were administered a novel, standardized test of script generation, which required participants to verbally generate and organize the necessary steps for completing six daily activities. HAND participants evidenced significantly more total errors, intrusions, and script boundary errors compared to the HIV- sample, indicating difficulties inhibiting irrelevant actions and staying within the prescribed boundaries of scripts, but had adequate knowledge of the relevant actions required for each script. These findings are generally consistent with the executive dysfunction and slowing common in HAND and suggest that script generation may play a role in everyday functioning problems in HIV.

Age differences in the perception of hierarchical structure in events

Everyday activities break down into parts and subparts, and appreciating this hierarchical structure is an important component of understanding. In two experiments we found age differences in the ability to perceive hierarchical structure in continuous activity. In both experiments, younger and older adults segmented movies of everyday activities into large and small meaningful events. Older adults' segmentation deviated more from group norms than did younger adults' segmentation, and older adults' segmentation was less hierarchically organized than that of younger adults. Older adults performed less well than younger adults on event memory tasks. In some cases, measures of event segmentation discriminated between those older adults with better and worse memory. These results suggest that the hierarchical encoding of ongoing activity declines with age, and that such encoding may be important for memory.

Social cognition, executive functioning, and neuroimaging correlates of empathic deficits in frontotemporal dementia

The authors investigated aspects of interpersonal sensitivity and perspective-taking in relation to empathy, social cognitions, and executive functioning in 26 frontotemporal dementia (FTD) patients. Behavioral-variant FTD (bvFTD) patients were significantly impaired on caregiver assessments of empathy, although self-ratings were normal. Progressive nonfluent aphasia and semantic-dementia samples were rarely abnormal. In bvFTD, empathy ratings were found to be correlated with social cognition and executive functioning measures, but not depression. Voxel-based morphometry revealed that reduced empathic perspective-taking was related to bifrontal and left anterior temporal atrophy, whereas empathic emotions were related to right medial frontal atrophy. Findings suggest that bvFTD causes multiple types of breakdown in empathy, social cognition, and executive resources, mediated by frontal and temporal disease.

Knowing Your Lines but Missing Your Cue: Rostral Prefrontal Lesions Impair Prospective Memory Cue Detection, but Not Action-intention Superiority

Prospective memory (PM) deficits are a common consequence of lesions to PFC, but their underlying neurocognitive mechanisms and processes are poorly understood. Here, we report on a patient, Z. P., who suffers from a chronic focal PM deficit, while other cognitive functions including memory are intact. His lesion involves right polar PFC (Brodmann's areas 10 and 9). Z. P. was very impaired on tasks that require detection of PM cues during an ongoing task. He was impaired regardless of whether the PM cues involved effortful or nearly effortless detection on the part of controls. By contrast, on tasks that tap the underlying (implicit) representations of intentions to perform an action, Z. P. showed normal patterns of intention superiority effects (ISEs) for to-be-performed actions and an inhibition effect for prospective actions after they had been performed. Thus, this is the first report of a neuropsychological dissociation between preserved privileged representation of prospective intentions and impaired detection of cues that support the opportune recovery of PM. Our data are compatible with the “gateway hypothesis” of rostral PFC, but also suggest there are components that are unique to PM and that remain intact after lesions to this region.

How to make a spaghetti sauce with a dozen small things I cannot name: a review of the impact of semantic-memory deficits on everyday actions

The purpose of this article is to present current evidence regarding the role of semantic memory in everyday actions. First we describe key models of everyday actions. We then discuss current evidence regarding the role of semantic memory in everyday actions. We reviewed articles reporting on the execution and representation of everyday actions in populations with semantic-memory deficits and single-object use in patients with semantic dementia. Although the evidence is sparse, the general conclusion of this review is that semantic memory seems necessary to support everyday actions. Finally, future challenges and research perspectives are discussed.

Neuroscience, moral reasoning, and the law

Modern advancements in functional magnetic resonance imaging (fMRI) technology have given neuroscientists the opportunity to more fully appreciate the brain's contribution to human behavior and decision making. Morality and moral reasoning are relative newcomers to the growing literature on decision neuroscience. With recent attention given to the salience of moral factors (e.g. moral emotions, moral reasoning) in the process of decision making, neuroscientists have begun to offer helpful frameworks for understanding the interplay between the brain, morality, and human decision making. These frameworks are relatively unfamiliar to the community of forensic psychologists, despite the fact that they offer an improved understanding of judicial decision making from a biological perspective. This article presents a framework reviewing how event-feature-emotion complexes (EFEC) are relevant to jurors and understanding complex criminal behavior. Future directions regarding converging fields of neuroscience and legal decision making are considered.

The neural basis of moral cognition: sentiments, concepts, and values

The human moral nature has perplexed laymen and academics for millennia. Recent developments in cognitive neuroscience are opening new venues for unveiling the complex psychological and neurobiological mechanisms underling human morality and its impairments. Here we review these lines of evidence and key topics of debate and explain why investigating the mechanisms of cognition-emotion interaction and of the neural bases of moral sentiments and values will be critical for our understanding of the human moral mind.

What day is today? A social-psychological investigation into the process of time orientation

Social-psychological research on time has pointed to the social construct of time rather than a mere physical entity that we reflect cognitively. Using two paradigms (day retrieval process and goal priming), the authors show that the time orientation is strongly prone to social influences and argue that a self-regulatory process underlies these findings. The degree of social comparison orientation in Study 1 and the degree of identification with groups for which the landmark is relevant (Study 2) both moderate the functionality of the landmarks within time orientation. Consistent with these findings, Studies 3 and 4 offer evidence that the activation of a personally relevant goal activates the day of goal attainment, a process that again can be moderated by social comparison orientation and identification. Overall, these results suggest a socially regulated time orientation. The internal clock (if any) is at least partly a "social clock."

A psychological and neuroanatomical model of obsessive-compulsive disorder

Imaging, surgical, and lesion studies suggest that the prefrontal cortex (orbitofrontal and anterior cingulate cortexes), basal ganglia, and thalamus are involved in the pathogenesis of obsessive-compulsive disorder (OCD). On the basis of these findings several models of OCD have been developed, but have had difficulty fully integrating the psychological and neuroanatomical findings of OCD. Recent research in the field of cognitive neuroscience on the normal function of these brain areas demonstrates the role of the orbitofrontal cortex in reward, the anterior cingulate cortex in error detection, the basal ganglia in affecting the threshold for activation of motor and behavioral programs, and the prefrontal cortex in storing memories of behavioral sequences (called "structured event complexes" or SECs). The authors propose that the initiation of these SECs can be accompanied by anxiety that is relieved with completion of the SEC, and that a deficit in this process could be responsible for many of the symptoms of OCD. Specifically, the anxiety can form the basis of an obsession, and a compulsion can be an attempt to receive relief from the anxiety by repeating parts of, or an entire, SEC. The authors discuss empiric support for, and specific experimental predictions of, this model. The authors believe that this model explains the specific symptoms, and integrates the psychology and neuroanatomy of OCD better than previous models.

Individual differences in moral judgment competence influence neural correlates of socio-normative judgments

To investigate how individual differences in moral judgment competence are reflected in the human brain, we used event-related functional magnetic resonance imaging, while 23 participants made either socio-normative or grammatical judgments. Participants with lower moral judgment competence recruited the left ventromedial prefrontal cortex and the left posterior superior temporal sulcus more than participants with greater competence in this domain when identifying social norm violations. Moreover, moral judgment competence scores were inversely correlated with activity in the right dorsolateral prefrontal cortex (DLPFC) during socio-normative relative to grammatical judgments. Greater activity in right DLPFC in participants with lower moral judgment competence indicates increased recruitment of rule-based knowledge and its controlled application during socio-normative judgments. These data support current models of the neurocognition of morality according to which both emotional and cognitive components play an important role.

Multilevel structure in behaviour and in the brain: a model of Fuster's hierarchy

A basic question, intimately tied to the problem of action selection, is that of how actions are assembled into organized sequences. Theories of routine sequential behaviour have long acknowledged that it must rely not only on environmental cues but also on some internal representation of temporal or task context. It is assumed, in most theories, that such internal representations must be organized into a strict hierarchy, mirroring the hierarchical structure of naturalistic sequential behaviour. This article reviews an alternative computational account, which asserts that the representations underlying naturalistic sequential behaviour need not, and arguably cannot, assume a strictly hierarchical form. One apparent liability of this theory is that it seems to contradict neuroscientific evidence indicating that different levels of sequential structure in behaviour are represented at different levels in a hierarchy of cortical areas. New simulations, reported here, show not only that the original computational account can be reconciled with this alignment between behavioural and neural organization, but also that it gives rise to a novel explanation for how this alignment might develop through learning.

Investigating dimensional organization in scripts using the pupillary response

Scripts are mental representations of activities in memory and are thought to be organized dimensionally in a temporal dimension. We investigated the cognitive strategies during the processing of temporal order of an event sequence to gain insight into the organization of scripts. Subjects were presented with triplets of script events (A - B - C). Fifty percent of the items included sequence violations at different positions within the triplet (late: A - C - B, or early: C - A - B). Reaction times indicate that subjects use an economical strategy by comparing the relative temporal positions of event pairs (e.g., A vs. B and if necessary B vs. C) and only attend to information that is necessary. Pupil data and error rates indicate that the temporal information of the complete sequence affects the decision process even if the first event pair indicates that temporal order has been violated. Results are seen as evidence of a dimensional structure of scripts.

Tool use and related errors in ideational apraxia: the quantitative simulation of patient error profiles

The behaviour of ideational apraxic patients on simple tasks involving multiple objects is typically marked by a variety of errors. While some of these errors concern the sequential organisation of action through time, many relate to the misuse of, or failure to use, necessary or appropriate tools. In this paper we apply the computational model of Cooper and Shallice (2000) to five standard multiple object tasks used in clinical assessment and demonstrate how, when lesioned, the model can account for the error profiles of two ideational apraxic patients discussed by Rumiati et al. (2001). Application of the model to the multiple object tasks demonstrates the generality of the model, while the account of the error profiles extends previous work (Cooper et al., 2005) in which ideational apraxia was argued to arise from a generalised disturbance of object representations that are held to trigger action schemas.

Functional organization of monkey brain for abstract operation

When humans manipulate a control device under operational rules, with the goal of indirectly controlling a remote tool to achieve a desired outcome, they may rely on the power of internal representation to organize individual moves of the controller and tool into a set of sequences by mapping the motor space among hand, controller and tool. We recently used functional brain imaging (PET) to investigate activations in monkey brain associated with joystick-controlled remote operation of a shovel to obtain food. Activated areas included the prefrontal cortex, posterior parietal cortex and cerebellum, regardless of the rules relating movements of the joystick to those of the shovel (Obayashi et al., 2004). If those areas are engaged in the mental manipulation of internal representation, then we should expect brain activity in the same regions during any similar remote operation, even with different controllers and/or operational rules. To address the above hypothesis in the current study, we used PET to measure regional cerebral blood flow (rCBF) of two monkeys during a task in which they were required to control a shovel remotely (to fetch a food pellet) by manipulating dual dials. Compared to unplanned movement of the dials, the active dual-dial operation was associated with robust activation of the prefrontal cortex, higher-order motor cortex, posterior parietal cortex and cerebellum, quite similar to that observed during remote operation with a joystick. The present study suggests that monkeys might be able to organize abstract sequential operations according to learned rules, and perhaps indeed to have insight into the nature of the causal relationships, implying the existence of a relatively sophisticated system of internal representation in the absence of language. The fact that the present results are consistent with our previous PET studies strengthens the view that the underlying mechanism for implicit manipulation of internal representations may involve a cerebro-cerebellar neural circuit including the frontal and parietal cortex.

The emergence of depression in adolescence: development of the prefrontal cortex and the representation of reward

Adolescent development is accompanied by the emergence of a population-wide increase in vulnerability to depression that is maintained through adulthood. We provide a model for understanding how this vulnerability to depression arises, and why depression is so often precipitated by social rejection or loss of status during this phase. There is substantial remodeling and maturation of the dopaminergic reward system and the prefrontal cortex during adolescence, that coincides with the adolescent entering the complex world of adult peer and romantic relationships, where the rewards that can be obtained (feelings such as belonging, romantic love, status and agency) are abstract and temporally distant from the proximal context. Development of the prefrontal cortex makes it possible to pursue such complex and distal rewards, which are, however, tenuous and more readily frustrated than more immediate rewards. We hypothesize that when these distant rewards are frustrated they suppress the reward system, and that when such suppression is extensive and occurs for long enough, the clinical picture that results is one of depression.

The parent-infant dyad and the construction of the subjective self

Developmental psychology and psychopathology has in the past been more concerned with the quality of self-representation than with the development of the subjective agency which underpins our experience of feeling, thought and action, a key function of mentalisation. This review begins by contrasting a Cartesian view of pre-wired introspective subjectivity with a constructionist model based on the assumption of an innate contingency detector which orients the infant towards aspects of the social world that react congruently and in a specifically cued informative manner that expresses and facilitates the assimilation of cultural knowledge. Research on the neural mechanisms associated with mentalisation and social influences on its development are reviewed. It is suggested that the infant focuses on the attachment figure as a source of reliable information about the world. The construction of the sense of a subjective self is then an aspect of acquiring knowledge about the world through the caregiver's pedagogical communicative displays which in this context focuses on the child's thoughts and feelings. We argue that a number of possible mechanisms, including complementary activation of attachment and mentalisation, the disruptive effect of maltreatment on parent-child communication, the biobehavioural overlap of cues for learning and cues for attachment, may have a role in ensuring that the quality of relationship with the caregiver influences the development of the child's experience of thoughts and feelings.