Individual differences of visual imagery ability in the benefit of a survival judgment task

This study investigated whether or not visual imagery ability affected the benefit of a survival judgment task. Based on the median split of their VVIQ score, 92 undergraduate students were classified as either high imagers (n = 46) or low imagers (n = 46). In the survival task, participants were requested to judge whether an item presented in the form of two Chinese characters was necessary or not in a survival situation. In the image judgment task, participants were requested to judge whether an item presented in the form of two Chinese characters arouses mental images or not. Participants were presented 18 concrete nouns at 4 s intervals in each condition. In both the survival judgment and the image judgment tasks, high imagers recalled more words than low imagers did. This result showed that imagery ability influenced the benefit of the survival judgment task. These results were discussed from the functional perspective of memory. Finally, we proposed the combination hypothesis, which combined elaboration and functional perspectives to explain the benefit of the survival judgment task.     

Silent music reading: Auditory imagery and visuotonal modality transfer in singers and non-singers

In daily life, responses are often facilitated by anticipatory imagery of expected targets which are announced by associated stimuli from different sensory modalities. Silent music reading represents an intriguing case of visuotonal modality transfer in working memory as it induces highly defined auditory imagery on the basis of presented visuospatial information (i.e. musical notes). Using functional MRI and a delayed sequence matching-to-sample paradigm, we compared brain activations during retention intervals (10 s) of visual (VV) or tonal (TT) unimodal maintenance versus visuospatial-to-tonal modality transfer (VT) tasks. Visual or tonal sequences were comprised of six elements, white squares or tones, which were low, middle, or high regarding vertical screen position or pitch, respectively (presentation duration: 1.5 s). For the cross-modal condition (VT, session 3), the visuospatial elements from condition VV (session 1) were re-defined as low, middle or high “notes” indicating low, middle or high tones from condition TT (session 2), respectively, and subjects had to match tonal sequences (probe) to previously presented note sequences. Tasks alternately had low or high cognitive load. To evaluate possible effects of music reading expertise, 15 singers and 15 non-musicians were included. Scanner task performance was excellent in both groups. Despite identity of applied visuospatial stimuli, visuotonal modality transfer versus visual maintenance (VT > VV) induced “inhibition” of visual brain areas and activation of primary and higher auditory brain areas which exceeded auditory activation elicited by tonal stimulation (VT > TT). This transfer-related visual-to-auditory activation shift occurred in both groups but was more pronounced in experts. Frontoparietal areas were activated by higher cognitive load but not by modality transfer. The auditory brain showed a potential to anticipate expected auditory target stimuli on the basis of non-auditory information and sensory brain activation rather mirrored expectation than stimulation. Silent music reading probably relies on these basic neurocognitive mechanisms.     

Individual differences in spatial mental imagery

In this article, we report a new image-scanning paradigm that allowed us to measure objectively individual differences in spatial mental imagery—specifically, imagery for location. Participants were asked to determine whether an arrow was pointing at a dot using a visual mental image of an array of dots. The degree of precision required to discriminate “yes” from “no” trials was varied. In Experiment 1, the time to scan increasing distances, as well as the number of errors, increased when greater precision was required to make a judgement. The results in Experiment 2 replicated those results while controlling for possible biases. When greater precision is required, the accuracy of the spatial image becomes increasingly important—and hence the effect of precision in the task reflects the accuracy of the image. In Experiment 3, this measure was shown to be related to scores on the Paper Folding test, on the Paper Form Board test, and on the visuospatial items on Raven's Advanced Progressive Matrices—but not to scores on questionnaires measuring object–based mental imagery. Thus, we provide evidence that classical standardized spatial tests rely on spatial mental imagery but not object mental imagery.     

EEG and fMRI agree: Mental arithmetic is the easiest form of imagery to detect

fMRI and EEG during mental imagery provide alternative methods of detecting awareness in patients with disorders of consciousness (DOC) without reliance on behaviour. Because using fMRI in patients with DOC is difficult, studies increasingly employ EEG. However, there has been no verification that these modalities provide converging information at the individual subject level. The present study examined simultaneous EEG and fMRI in healthy volunteers during six mental imagery tasks to determine whether one mental imagery task generates more robust activation across subjects; whether activation can be predicted from familiarity with the imagined activity; and whether EEG and fMRI converge upon the same conclusions about individual imagery performance. Mental arithmetic generated the most robust activation in the majority of subjects for both EEG and fMRI, and level of activation could not be predicted from familiarity, with either modality. We conclude that overall, EEG and fMRI agree regarding individual mental imagery performance.     

运动技能水平与躯体感觉输入对运动表象的影响

运动表象质量与运动技能水平有关,运动表象质量随着运动技能水平的提高而上升。器械使用可使人脑产生可塑性改变,使用者会将器械纳入身体图式。然而,两者影响运动表象的神经心理机制还不清楚。本研究采用功能性磁共振成像探析篮球运动员与新手在不同持球条件下表象投篮时脑功能活动的差异。结果表明运动员表象质量较好,镜像神经系统激活高于新手;持球条件下运动员表象质量显著高于不持球条件下,镜像神经系统激活程度显著低于不持球条件下。研究说明持器械可以显著提高运动员的表象质量,器械使用带来镜像神经系统的可塑性变化。     

Individual differences in visual imagery determine how event information is remembered

Individuals differ in how they mentally imagine past events. When reminiscing about a past experience, some individuals remember the event accompanied by rich visual images, while others will remember it with few of these images. In spite of the implications that these differences in the use of imagery have to the understanding of human memory, few studies have taken them into consideration. We examined how imagery interference affecting event memory retrieval was differently modulated by spatial and object imagery ability. We presented participants with a series of video-clips depicting complex events. Participants subsequently answered true/false questions related to event, spatial, or feature details contained in the videos, while simultaneously viewing stimuli that interfered with visual imagery processes (dynamic visual noise; DVN) or a control grey screen. The impact of DVN on memory accuracy was related to individual differences in spatial imagery ability. Individuals high in spatial imagery were less accurate at recalling details from the videos when simultaneously viewing the DVN stimuli compared to those low in spatial imagery ability. This finding held for questions related to the event and spatial details but not feature details. This study advocates for the inclusion of individual differences when studying memory processes.     

Mood stability versus mood instability in bipolar disorder: a possible role for emotional mental imagery

A cognitive model of bipolar disorder suggests that mental imagery acts as an emotional amplifier of mood and may be heightened in bipolar disorder. First, we tested whether patients with bipolar disorder would score higher on mental imagery measures than a matched healthy control group. Second, we examined differences in imagery between patients divided into groups according to their level of mood stability. Mood ratings over approximately 6-months, made using a mobile phone messaging system, were used to divide patients into stable or unstable groups. Clinician decisions of mood stability were corroborated with statistical analysis. Results showed (I) compared to healthy controls, patients with bipolar disorder had significantly higher scores for general mental imagery use, more vivid imagery of future events, higher levels of intrusive prospective imagery, and more extreme imagery-based interpretation bias; (II) compared to patients with stable mood, patients with unstable mood had higher levels of intrusive prospective imagery, and this correlated highly with their current levels of anxiety and depression. The findings were consistent with predictions. Further investigation of imagery in bipolar disorder appears warranted as it may highlight processes that contribute to mood instability with relevance for cognitive behaviour therapy.     

Prototype-distortion category learning: a two-phase learning process across a distributed network

This paper reviews a body of work conducted in our laboratory that applies functional magnetic resonance imaging (fMRI) to better understand the biological response and change that occurs during prototype-distortion learning. We review results from two experiments (Little, Klein, Shobat, McClure, & Thulborn, 2004; Little & Thulborn, 2005) that provide support for increasing neuronal efficiency by way of a two-stage model that includes an initial period of recruitment of tissue across a distributed network that is followed by a period of increasing specialization with decreasing volume across the same network. Across the two studies, participants learned to classify patterns of random-dot distortions (Posner & Keele, 1968) into categories. At four points across this learning process subjects underwent examination by fMRI using a category-matching task. A large-scale network, altered across the protocol, was identified to include the frontal eye fields, both inferior and superior parietal lobules, and visual cortex. As behavioral performance increased, the volume of activation within these regions first increased and later in the protocol decreased. Based on our review of this work we propose that: (i) category learning is reflected as specialization of the same network initially implicated to complete the novel task, and (ii) this network encompasses regions not previously reported to be affected by prototype-distortion learning.     

Music to the inner ears: Exploring individual differences in musical imagery

In two studies, we explored the frequency and phenomenology of musical imagery. Study 1 used retrospective reports of musical imagery to assess the contribution of individual differences to imagery characteristics. Study 2 used an experience sampling design to assess the phenomenology of musical imagery over the course of one week in a sample of musicians and non-musicians. Both studies found episodes of musical imagery to be common and positive: people rarely wanted such experiences to end and often heard music that was personally meaningful. Several variables predicted musical imagery, including personality, musical preferences, and positive mood. Musicians tended to hear musical imagery more often, but they reported less frequent episodes of deliberately-generated imagery. Taken together, the present research provides new insights into individual differences in musical imagery, and it supports the emerging view that such experiences are common, positive, and more voluntary than previously recognized.     

Event-related fMRI of category learning: differences in classification and feedback networks

Eighteen healthy young adults underwent event-related (ER) functional magnetic resonance imaging (fMRI) of the brain while performing a visual category learning task. The specific category learning task required subjects to extract the rules that guide classification of quasi-random patterns of dots into categories. Following each classification choice, visual feedback was presented. The average hemodynamic response was calculated across the eighteen subjects to identify the separate networks associated with both classification and feedback. Random-effects analyses identified the different networks implicated during the classification and feedback phases of each trial. The regions included prefrontal cortex, frontal eye fields, supplementary motor and eye fields, thalamus, caudate, superior and inferior parietal lobules, and areas within visual cortex. The differences between classification and feedback were identified as (i) overall higher volumes and signal intensities during classification as compared to feedback, (ii) involvement of the thalamus and superior parietal regions during the classification phase of each trial, and (iii) differential involvement of the caudate head during feedback. The effects of learning were then evaluated for both classification and feedback. Early in learning, subjects showed increased activation in the hippocampal regions during classification and activation in the heads of the caudate nuclei during the corresponding feedback phases. The findings suggest that early stages of prototype-distortion learning are characterized by networks previously associated with strategies of explicit memory and hypothesis testing. However as learning progresses the networks change. This finding suggests that the cognitive strategies also change during prototype-distortion learning.     

Role of Functional Magnetic Resonance Imaging in Drug Discovery

In this review, we survey the state of the field of functional magnetic resonance imaging (fMRI) as it relates to drug discovery and drug development. We highlight the advantages and limitations of fMRI for this purpose and suggest ways to improve the use of fMRI for developing new therapeutics, with emphasis on treatments for anxiety disorders. Fundamentally, pharmacological studies with standard psychiatric treatments using standardized behavioral probes during fMRI will need to be carried out to determine characteristic brain signatures that could be used to predict whether novel compounds are likely to have specific therapeutic effects.     

The neural basis of cognitive control: Response selection and inhibition

The functional neuroanatomy of tasks that recruit different forms of response selection and inhibition has to our knowledge, never been directly addressed in a single fMRI study using similar stimulus–response paradigms where differences between scanning time and sequence, stimuli, and experimenter instructions were minimized. Twelve right-handed participants were scanned on two standard cognitive control tasks, a stimulus–response incompatibility task, and a response inhibition task. A compound trial design allowed comparison of preparing to inhibit an upcoming automatic response to wholly inhibiting an automatic response. Furthermore, inhibiting an automatic response to perform an alternative task-relevant response was compared to wholly inhibiting an automatic response. No differences were found in prefrontal activity when preparing to inhibit an automatic response was compared to wholly inhibiting an automatic response, suggesting a mostly common network. The left inferior frontal gyrus was found to be commonly recruited during both tasks when controlled responses were required, likely due to its role in response selection. In contrast, the right inferior frontal gyrus was found to be more involved when task demands were stronger for response inhibition. Our results are largely consistent with models of cognitive control that postulate that separate psychological constructs, such as response selection and inhibition, are related processes largely served by a common prefrontal network. This prefrontal network is recruited to a greater or lesser extent depending on specific task demands.     

Effects of motor intention on the perception of somatosensory events: A behavioural and functional magnetic resonance imaging study

The intention to execute a movement can modulate our perception of sensory events, and this modulation is observed ahead of both ocular and upper limb movements. However, theoretical accounts of these effects, and also the empirical data, are often contradictory. Accounts of “active touch”, and the premotor theory of attention, have emphasized how movement intention leads to enhanced perceptual processing at the target of a movement, or on the to-be-moved effector. By contrast, recent theories of motor control emphasize how internal “forward” model (FM) estimates may be used to cancel or attenuate sensory signals that arise as a result of self-generated movements. We used behavioural and functional brain imaging (functional magnetic resonance imaging, fMRI) to investigate how perception of a somatosensory stimulus differed according to whether it was delivered to a hand that was about to execute a reaching movement or the alternative, nonmoving, hand. The results of our study demonstrate that a somatosensory stimulus delivered to a hand that is being prepared for movement is perceived to have occurred later than when that same stimulus is delivered to a nonmoving hand. This result indicates that it takes longer for a tactile stimulus to be detected when it is delivered to a moving limb and may correspond to a change in perceptual threshold. Our behavioural results are paralleled by the results of our fMRI study that demonstrated that there were significantly reduced blood-oxygen-level-dependent (BOLD) responses within the parietal operculum and insula following somatosensory stimulation of the hand being prepared for movement, compared to when an identical stimulus was delivered to a nonmoving hand. These findings are consistent with the prediction of FM accounts of motor control that postulate that central sensory suppression of somatosensation accompanies self-generated limb movements, and with previous reports indicating that effects of sensory suppression are observed in higher order somatosensory regions.     

Imagery and self-efficacy in the injury context

ObjectivesTo develop and test the factorial validity of an adapted version of the Athletic Injury Imagery Questionnaire (AIIQ-2: Sordoni, Hall, & Forwell, 2002). To explore the effect of an imagery intervention on self-efficacy in the sport injury context.DesignStudy 1, cross-sectional; Study 2, multiple-base line.MethodIn Study 1 the AIIQ-2 was adapted to include a pain management subscale. This adapted imagery questionnaire (AIIQ-3) was then administered to 291 injured athletes (M age = 28.64 years, SD = 14.30). In Study 2 using a multiple-baseline single subject design, the effects of an imagery intervention on self-efficacy prior to physiotherapy treatment of five athletes with a Type B malleolar fracture (M age = 49.50 years, SD = 16.56) was examined. A follow-up post-experimental interview explored participants' perceptions of the intervention.ResultsStudy 1, confirmatory factor analysis revealed evidence for the factorial validity of the AIIQ-3. Study 2, results from the multiple-base line design demonstrated that for two out of the five participants there were observable and statistically meaningful increases in task efficacy, with the same result in three out of five participants for coping efficacy. The post-interview results revealed that all intervention participants perceived the intervention to be beneficial and effective beyond the general information provided.ConclusionsThe results are discussed in terms of overcoming an inherent weakness in previous injury-related imagery research and the applied implications for the time-course of rehabilitation.     

Role of left posterior superior temporal gyrus in phonological processing for speech perception and production

Models of both speech perception and speech production typically postulate a processing level that involves some form of phonological processing. There is disagreement, however, on the question of whether there are separate phonological systems for speech input versus speech output. We review a range of neuroscientific data that indicate that input and output phonological systems partially overlap. An important anatomical site of overlap appears to be the left posterior superior temporal gyrus. We then present the results of a new event-related functional magnetic resonance imaging (fMRI) experiment in which participants were asked to listen to and then (covertly) produce speech. In each participant, we found two regions in the left posterior superior temporal gyrus that responded both to the perception and production components of the task, suggesting that there is overlap in the neural systems that participate in phonological aspects of speech perception and speech production. The implications for neural models of verbal working memory are also discussed in connection with our findings.     

The role of visual imagery in the enhanced cognitive interview: guided questioning techniques and individual differences

The cognitive interview utilises mnemonics and other techniques to facilitate obtaining information from victims and witnesses. Research has indicated superior recall to standard police interviews. However, there has been minimal research regarding the role of individual differences. One area that has generated spirited theoretical debate is imagery ability, as guided imagery questioning is an important part of the enhanced cognitive interview. Imagery is also arguably an integral part of several mnemonics employed in the technique. The present study investigated the role of individual differences in imagery ability, as well as the effect of explicit instructions to image, on recall performance. Participants completed the Vividness of Visual Imagery Questionnaire (VVIQ), witnessed a film of a simulated crime, and were interviewed using the cognitive interview or a structured interview. While recall in the cognitive interview was superior, VVIQ scores had little relationship with recall of information. Further, recall elicited by guided imagery differed only minimally from that obtained using standard questioning in the structured interview. These results suggested that the relaxation and rapport building common to questioning in both interview conditions may evoke spontaneous imagery that is comparable to explicit instructions to image, regardless of individuals' inherent imagery ability. Future directions are discussed, including research focused on individual differences and a practical emphasis on context reinstatement and social facilitative techniques. Copyright © 2004 John Wiley & Sons, Ltd.     

Motor imagery ability and internal representation of movement in children with probable developmental coordination disorder

It has been hypothesised that deficits in the functioning of the mirror neuron system (MNS) and internal modelling may contribute to the motor impairments associated with DCD. These processes can be explored behaviourally through motor imagery paradigms. Motor imagery proficiency of children with and without probable DCD (pDCD) was examined using a complex hand rotation task to explore whether motor imagery strategies could be used during more complex tasks. Forty-four boys aged 7–13 years participated, 22 with pDCD (mean = 9.90 years ± 1.57) and 22 controls (mean = 9.68 years ± 1.53). Participants completed the task twice: with and without motor imagery instructions. Stimuli were presented in two rotational axes – palm/back, and eight 45° rotational steps. Both groups showed evidence of following the biomechanical and postural constraints of actual movements. Responses of children with pDCD were slower and less accurate than controls, with group differences increasing alongside task complexity. A greater impact of biomechanical constraints for accuracy was observed in the DCD group. The response characteristics of children with pDCD likely reflects a reduced capacity to mentally manipulate a body schema and reduced visuo-motor processing capabilities. Behaviourally, these processes are linked to MNS and internal modelling function, suggesting deficits in these systems may contribute to the movement difficulties characteristic of DCD.     

Neuroanatomical correlates of processing in visual and visuospatial working memory

Working memory is traditionally seen as being organised in a modular way with a central executive orchestrating at least two slave systems (phonological loop and visuospatial sketch pad). Neuroanatomical correlates of the visual and visuospatial subsystems and the central executive are discussed in this article. A series of experiments are presented yielding evidence for a differentiation into active and passive processing in working memory as well as their neuroanatomical correlates in the prefrontal cortex. Data, yielding evidence for an interaction and separation of visual and visuospatial working memory are presented and discussed. Further results are presented which suggest a convergence of these two systems with increasing working memory demands. The discussed findings will give new insight in the organisation of visual and visuospatial working memory on the anatomical level.