Visualizing Emotional Arousal within the Context of Body Size Evaluation: A Pilot Study of Steady-State Visual Evoked Potentials in Women with Anorexia Nervosa and Healthy Controls

Behavioral, neuronal, and physiological facets of multidimensional body image in anorexia nervosa: a scoping review

Body image is a core identity facet in anorexia nervosa (AN). Current literature outlines body image as a multidimensional construct, characterized by perceptual, cognitive, and emotional components, which explain how individuals perceive, think, and behave in relation to their body. The purpose of this scoping review is to uncover neuropsychological disturbances in AN related to body image by focusing on its different behavioral and neuronal assessments, aiming to provide a broad overview of common findings and limitations. Additionally, we explore the role of somato-sensory/somato-motor components and physiological markers underlying body image disturbances, which have not been extensively examined in previous studies. Literature screening was performed across three databases (PubMed, PsycINFO, Scopus). We classified behavioral, physiological, and neuroimaging studies according to their degree of involvement with body image dimensions and discussed the primary findings for each component. A total of 4015 studies were identified, of which 107 were eligible (84 behavioral and 23 neuroimaging studies) based on eligibility criteria, covering research from 1973 to 2024. Notably, of those which specified the following factors: 16 studies focused on the restrictive subtype (AN-r), two on the binge-eating/purging subtype (AN-b/p), and 19 examined both AN-r and AN-b/p; finally four on the atypical subtype; 11 on the weight-recovered state (WR) and three included also male participants. The mean age across all studies was 20.1 years (SD = 3.79). Our findings reveal that body image disturbances in AN are not limited to the overestimation of body size but also encompass cognitive, emotional, and somato-sensory aspects. A strong drive for thinness emerged as a prominent cognitive factor in maintaining the disturbance, along with altered autobiographical recall, executive function, and attentional biases toward body-related stimuli. Emotional regulation difficulties, altered interoceptive awareness, and distorted somato-sensory aspects-reflected in tactile and motor processes-were highlighted. In addition, increased autonomic reactivity to body image stimuli, indicating a sympathetic/parasympathetic imbalance, is supported by specific cortical-subcortical functional alterations. Our review emphasizes that body image distortion in AN should not be viewed merely as a perceptual deficit but rather as a complex cognitive-emotional and somato-sensory process.

Deficits in auditory and visual steady-state responses in adolescents with bipolar disorder

BACKGROUND

Many aspects of steady-state responses of the brain remain unclear in bipolar disorder (BD) due to the small number of auditory steady-state response (ASSR) studies and the lack of steady-state visual evoked potential (SSVEP) studies on this complex disorder. Therefore, we assessed the patterns of SSVEP and ASSR in adolescents with BD during an active task to detect possible deficits in these important brain responses compared to normal subjects.

METHODS

27 adolescents with BD and 30 healthy adolescents were assessed in this study. The blinking background of the monitor presented at 15 Hz and the tone signal stimulation at 40 Hz evoked SSVEPs and ASSRs, respectively. The phase and amplitude of the steady-state responses were calculated in the auditory and visual conditions.

RESULTS

Patients exhibited a substantially worse performance in the motor control inhibition task during both auditory and visual modalities. Patients showed increased SSVEP amplitude and phase in the frontal region compared to control adolescents. Also, patients exhibited decreased ASSR amplitude in the prefrontal and increased ASSR amplitude in the right-frontal and centro-parietal areas compared to healthy adolescents.

CONCLUSIONS

impairments in the production and preservation of SSVEP and ASSR are evident in BD, implicating abnormalities in visual and auditory pathways. Neurophysiological deficits and worse performance in BD adolescents may imply that visual and auditory pathways cannot well transfer the pertinent information from arriving sensory data to the visual and auditory cortices, and the frontal cortex cannot well integrate incoming signals into a unified and coherent perceptual action.