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The way we perceive signals coming from the inside of the body (i.e., interoception) may influence the processing of information related to the self. In this study, we investigated whether interoceptive sensibility may play a role in autobiographical memory processes. We evaluated 41 healthy participants with a modified version of the Autobiographical Memory Test, also assessing specificity, vividness, emotional valence, and intensity for autobiographical and public memories. Participants completed a self-report questionnaire measuring interoceptive sensibility. Results showed that autobiographical memories were recalled with higher specificity, vividness, and emotional intensity than public memories. Interestingly, we found that participants with (self-reported) high interoceptive sensibility recalled more positive events in the autobiographical compared to the public condition. Our findings provided new evidence on the selective role of physiological aspects of bodily self-awareness in autobiographical memory, suggesting that interoception is fundamental for supporting adaptive emotion regulation processes when recollecting engrams related to the self., (Copyright © 2022 Elsevier Inc. All rights reserved.)

It is largely recognized that the mesial temporal lobe and its substructure support declarative long-term memory (LTM). So far, different theories have been suggested, and the organization of declarative verbal LTM in the brain is still a matter of debate. In the current study, we retrospectively selected 151 right-handed patients with temporal lobe epilepsy with and without hippocampal sclerosis, with a homogeneous (seizure-free) clinical outcome. We analyzed verbal memory performance within a normalized scores context, by means of prose recall and word paired-associate learning tasks. Patients were tested at presurgical baseline, 6months, 2 and 5years after anteromesial temporal lobe surgery, using parallel versions of the neuropsychological tests. Our main finding revealed a key involvement of the left temporal lobe and, in particular, of the left hippocampus in prose recall rather than word paired-associate task. We also confirmed that shorter duration of epilepsy, younger age, and withdrawal of antiepileptic drugs would predict a better memory outcome. When individual memory performance was taken into account, data showed that females affected by left temporal lobe epilepsy for longer duration were more at risk of presenting a clinically pathologic LTM at 5years after surgery. Taken together, these findings shed new light on verbal declarative memory in the mesial temporal lobe and on the behavioral signature of the functional reorganization after the surgical treatment of temporal lobe epilepsy., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Neuropsychological assessment is critical in both diagnosis and prognosis of patients with epilepsy. Beyond electrophysiological and anatomical alterations, other factors including different ethnic-cultural and linguistic backgrounds might affect neuropsychological performance. Only a few studies considered migration and acculturation effects and they typically concerned nonclinical samples. The current study aimed at investigating the influence of ethnic background and time spent in Italy on a full neuropsychological battery administered to both Italian and foreign-born patients and at providing a brief interview for obtaining relevant information on each patient's transcultural and language-related history. Clinical reports from 43 foreign-born patients with drug-resistant epilepsy were collected from the archives of Milan Niguarda Hospital. Epileptogenic zone, age, education, profession, illness duration, seizure frequency, handedness, and gender were considered in selecting 43 Italian controls. Ethnicity (Italian/foreign-born) and years spent in Italy were analyzed as main predictors on 21 neuropsychological scales by means of General(ized) Linear Models. An additional analysis studied two composite scores of overall verbal and nonverbal abilities. Ethnicity significantly affected the following: the verbal overall score, Verbal Fluency, Naming, Token-test, Digit Span, Attentional Matrices, Trail-Making-Test, Line-Orientation-Test, and Raven matrices; no effects were found on the nonverbal overall score, Word Pairs Learning, Episodic Memory, reading accuracy, visual span, Bells test, Rey Figure, and face memory and recognition. No significant effects of years spent in Italy emerged. While years spent in Italy does not predict neuropsychological performance, linguistic background had a strong impact on it. With respect to Italian-speaking patients, those who were foreign-born showed large task-related variability, with an especially low performance on language-related tests. Hence, language tests should not be considered as valid measures of neuropsychological impairment in this population, not even in foreign-born patients with good Italian fluency. Clinicians should consider such asymmetries in order to improve the accuracy of neuropsychological assessment of foreign-born patients., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Homeostatic parameters, such as temperature, are related to body representation. In this study, we measured whether caloric vestibular stimulation (CVS) alters body temperature and tactile processing, and if in the direction predicted by a holistic body matrix representation. Skin temperature and tactile two-point discrimination (TPD) acuity were measured for both arms before, immediately after and with a delay from CVS. Participants were also administered a personality questionnaire and an anxiety inventory to rule out confounding factors. Two control experiments were planned to exclude casual variations. Our results show that temperature drops significantly in both arms after CVS. CVS also induces a bilateral improvement in tactile acuity (even though not immediately after but in the delayed condition). Finally, these effects are not due to learning, as demonstrated by the control experiment. In summary, our results suggest that vestibular stimulation updates body representation, supporting the evidence in favor of a body matrix., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Three cognitive components may play a crucial role in both memory awareness and in anosognosia for memory deficit (AMD): (1) a personal data base (PDB), i.e., a memory store that contains "semantic" representations about the self, (2) monitoring processes (MPs) and (3) an explicit evaluation system (EES), or comparator, that assesses and binds the representations stored in the PDB with information obtained from the environment. We compared both the behavior and the functional connectivity (as assessed by resting-state fMRI) of AMD patients with aware patients and healthy controls. We found that AMD is associated with an impoverished PDB, while MPs are necessary to successfully update the PDB. AMD was associated with reduced functional connectivity within both the default-mode network and in a network that includes the left lateral temporal cortex, the hippocampus and the insula. The reduced connectivity between the hippocampus and the insular cortex was correlated with AMD severity., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Individuals with the peculiar disturbance of 'overcompleteness' experience an intense desire to amputate one of their healthy limbs, describing a sense of disownership for it (Body Integrity Identity Disorder - BIID). This condition is similar to somatoparaphrenia, the acquired delusion that one's own limb belongs to someone else. In ten individuals with BIID, we measured skin conductance response to noxious stimuli, delivered to the accepted and non-accepted limb, touching the body part or simulating the contact (stimuli approach the body without contacting it), hypothesizing that these individuals have responses like somatoparaphrenic patients, who previously showed reduced pain anticipation, when the threat was directed to the disowned limb. We found reduced anticipatory response to stimuli approaching, but not contacting, the unwanted limb. Conversely, stimuli contacting the non-accepted body-part, induced stronger SCR than those contacting the healthy parts, suggesting that feeling of ownership is critically related to a proper processing of incoming threats., (Copyright © 2015. Published by Elsevier Inc.)

Right brain damaged patients sometimes deny that their left arm is paralysed or even claim to have just moved it. This condition is known as anosognosia for hemiplegia (AHP). Here, we used fMRI to study patients with and without AHP during the execution of a motor task. We found that the delusional belief of having moved was preceded by brain activation of the cortical regions that are implicated in motor control in the left intact hemisphere and in the spared motor regions of the right hemisphere; patients without anosognosia did not present with the same degree of activation. We conclude that the false belief of movement is associated with a combination of strategically placed brain lesions and the preceding residual neural activity of the fronto-parietal motor network. These findings provide evidence that the activity of motor cortices contributes to our beliefs about the state of our motor system., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Neglect patients typically show motor perseveration while canceling targets on the ipsilesional side. This behavior can be influenced by the presence vs. absence of targets on the (neglected) contralesional side (). As alternative explanations, the authors proposed (i) directional hypokinesia--the patient cannot perform reaching movements towards detected left-sided targets, and thus carries on canceling on the right side, and (ii) allochiria--the patient misperceives left-sided targets as located on the right side, and cancels them there. We report here data from a patient (EZ) that might confirm the second hypothesis. EZ was presented with 19 displays in which the number and position of cancellation targets on both sides were varied systematically. EZ showed motor perseveration while canceling, but this tendency did not vary across conditions. Interestingly though, EZ also drew cancellation marks in the empty space between the ipsilesional targets, and this phenomenon was significantly more intense when there were more targets on the neglected side. As EZ's comments suggested, such a behavior might reflect the attempt to cancel out delusional targets. Our speculation is that those objects were generated by allochiria.

We report a presurgical fMRI study and a longitudinal behavioral and structural MRI study in a 26-year-old right-handed woman with drug-resistant epilepsy of the supplementary motor region with cytoarchitectural dysplasia and minimal cortico-subcortical gliotic damage. fMRI scans were acquired during a silent phonemic verbal fluency task (VF), an automatic counting task (CT), and a finger-tapping motor task (MT). These were all compared with rest. Presurgical neuropsychological assessment was substantially normal with only a minor deficit in the domain of visuo-constructive and complex motor-planning skills. Noticeably, performance on phonemic verbal fluency was normal. Presurgical fMRI results revealed a normal specialization of left SMA and pre-SMA, including a fine-grained somatotopy for mouth and hand representations despite epilepsy. Immediately after surgical removal of the epileptogenic zone (the posterior third of the superior and middle frontal gyri including pre-SMA and part of SMA, and part of the anterior cingulate region--all of which were active presurgically at the fMRI tests), the patient suffered from transcortical motor aphasia temporarily. One year after surgery, she still showed impaired performance in the verbal fluency tasks while naming and comprehension were recovered. The patient was now free from seizures. This fMRI study supports the case that repeated seizures per se may not be sufficient to alter the distribution of neural representations of cognitive function. Selective behavioral impairment after surgical removal of brain areas that were activated during presurgical fMRI permits us to establish a causal link between these activations and task performance. This link could not have been made on the basis of activation patterns or lesion data taken on their own. These findings support the case that some epileptic patients may represent a unique opportunity for cognitive neuroscience studies.

Neglect of contralesional stimuli and perseverative behavior on ipsilesional stimuli may co-occur on a target cancellation task. Our aim was to investigate whether the presence vs. absence of contralesional targets can modify perseveration on ipsilesional targets. We studied four right brain-damaged patients with left neglect and perseverative behavior on screening cancellation tasks. We compared their cancellation performance in two conditions: (i) targets equally distributed on both sides of space and (ii) targets confined to the right side. One patient showed no significant difference in perseveration between these two conditions; in contrast, three patients perseverated significantly more in condition (i) than in condition (ii). These results suggest that, at least in some patients, information from the 'neglected' targets is not completely lost, but rather it affects behavior in the ipsilesional side. The traditional dichotomy 'bad space-good space' would not apply here.