Cognitive and behavioral modernity in Homo erectus: skull globularity and hominin brain evolution

In this article we provide evidence that evolutionary pressures altered the cranial base and the mastoid region of the temporal bone more than the calvaria in the transition from H. erectus to H. sapiens. This process seems to have resulted in the evolution of more globular skull shape – but not as a result of expansion of the brain in the parietal regions but of reduction of the cranial base and the mastoid region relative to the parietals. Consequently, we argue that expansion of the parietals seems to be unrelated to brain evolution, but is more a by-product of reduction in other regions of the skull, reduction that may be related to dietary factors. Additionally, these findings suggest that cognitive and behavioural modernity may not necessarily be dependent on brain shape. Also, it cannot be attributed to the change in brain size because H. erectus and modern human cranial capacities overlap substantially. Consequently, we suggest H. erectus possessed the full suite of cognitive adaptations characteristic of modern humans without possessing a globular skull with flared parietals. Our results also support the theory that paedomorphic morphogenesis of the skull was important in the transition from H. erectus to H. sapiens and that such changes may be related to both dietary factors and social evolution.

Inhibitory function and sustained attention following galvanic vestibular stimulation in children with attention-deficit/hyperactivity disorder

Background and Aim: In recent years, galvanic vestibular stimulation (GVS) has been used as an effective method in rehabilitation and treat­ment of psychological disorders in children and adults. This study was designed to evaluate the effect of GVS on response inhibition and susta­ined attention in children with attention-deficit/ hyperactivity disorder (ADHD). Methods: Seventeen children with ADHD, within the age range of 9−12 years, participated in this study. All participants were exposed to the go/no-go task. The behavioral outcomes and event-related potentials were recorded at baseline status, in sham condition, and after 20 minutes of exposure to GVS polarities, with an anode on the right mastoid region and a cathode on the left mastoid region. Results: The results showed that there was a sig­nificant difference in reducing the behavioral response of the commission error (p < 0.05). But the reduction in behavioral responses to omission error and reaction time were not significant (p > 0.05). However, regarding ERPs, reduced latencies and increased amplitudes of N2 and P3 waves were observed in GVS intervention, com­pared to the baseline and sham conditions (p < 0.05). Conclusion: The present results indicated the potential of GVS in improving of cognition func­tion in children with ADHD and could help us develop a new strategy for rehabilitation of res­ponse inhibition disorders in the future. Keywords: Galvanic vestibular stimulation; attention-deficit/hyperactivity disorder; go/no-go task; event-related potentials; motor control

Isolated Congenital Mastoid Cholesteatoma with no Involvement of Aditus Ad Antrum and Middle Ear

Cholesteatoma is a non-neoplastic, keratinized squamous epithelial lesion that affects the temporal bone. The middle ear is the most frequent, while the isolated cholesteatoma of the mastoid is rare. The aim of this study was to describe a rare case of isolated mastoid cholesteatoma with no involvement of aditus ad antrum and middle ear including a literature review of the topic. This case report describes the case of a 58 years old female with a cholesteatoma isolated in the mastoid region, evidenced by imaging (computer tomography and magnetic resonance). A mastoidectomy was performed: mastoid process was completely involved, but antrum was not reached. Moreover, it reached the soft tissue of stylomastoid foramen as well as the posterior belly of the digastric muscle. In the literature few articles described cases of cholesteatoma isolated in the mastoid region. Research was conducted using PubMed and reference list and there were considered only reports about cholesteatoma exclusively located in the mastoid process without involvement of antrum or middle ear. Fourteen articles were included in this review, with a total number of 23 cases of cholesteatoma isolated in the mastoid region. All papers analyzed reported the cases of isolated mastoid cholesteatoma that presented a congenital origin. Its diagnosis is difficult, therefore, imaging evaluation is mandatory and surgery is the treatment of choice. Mastoid cholesteatomas without involvement of aditus ad antrum and middle ear are rare and only 23 cases are reported in literature. Our case is in line with all clinical and diagnostic features of this rare disease, but it is the only one that evidenced an exposure of the soft tissue of stylomastoid foramen as well as the posterior belly of the digastric muscle. The treatment of choice was the surgical one, avoiding damaging of important anatomo-functional structure.

Post-auricular dermoid cyst- uncommon lesion at an uncommon site

<p>Dermoid cyst in the post auricular region is a rare occurrence, with only a handful of cases described in the literature. It is an uncommon benign midline cyst which arises in the sub-cutaneous plane, but deeper extension into bone to intra-cranial and intra-calvarial has been reported. The usual presentation is asymptomatic, but it can present as a swelling gradually progressing in size, pain following secondary infection or rupture of the cyst. Malignant transformation of the cyst is exceedingly rare but has been reported. Here we discuss a case of a middle aged female with left dermoid cyst in the mastoid region which was excised surgically and showed no recurrence in the 6 month post-operative period. It is imperative to mention that the removal of the cyst with its wall in entirety is required to prevent recurrence. The final diagnosis is made based on the histo-pathological examination of the excised specimen. </p>

Evaluation of the Mastoid Emissary Canals with Computerized Tomography in Patients with Chronic Otitis Media

Background The mastoid emissary veins (MEVs) pass through the mastoid emissary canal-mastoid foramen (MEC-MF) in the mastoid region of the skull. MEVs can give rise to complications during surgical procedures. The purpose of our study was to investigate the morphological and morphometric characteristics of MECs of patients with clinical chronic otitis media (COM) using high-resolution computed tomography (HRCT). Methods Patients diagnosed with COM and undergoing temporal HRCT were identified by retrospectively scanning our hospital's automation system. Patients undergoing temporal HRCT for reasons other than COM, infection or tinnitus were identified for the control group by scanning the PACS archive. Sixty-two mastoid regions were examined in 38 unilateral and 12 bilateral COM patients, and 100 mastoid regions in the 50 patients in the control group. The presence of an accessory MEC-MF and MEC-MF diameters was evaluated in both groups. Results Main MEC diameters on the side of the ear with COM were 1.6 mm, and total accessory and main MEC diameters were 1.8 mm, both values being significantly higher than in the control group. Presence of accessory MEC on the side of the ear with COM was determined at 61.8%, significantly higher than in the control group. Conclusion Preoperative awareness of cranial venous drainage abnormalities is important to reduce surgical complications. Our study shows that MECs may be wider in diameter in patients with COM. MECs in COM patients must be identified before surgery to the mastoid region.

Mastoid Osteoma

Introduction Osteoma of the mastoid region is an uncommon benign tumor of bone. Osteomas may occur in the external auditory canals but are reported to be very rare in the mastoid region, with about 150 cases reported in literature. Case Report A 20-year-old man presented with painless lump behind the right ear since last 2 years. On examination a 3x3 cm tumour was present in the right post-auricular region. HRCT scan showing hyper-attenuating area close to the right mastoid cortex, measuring approximately 3x3cm, spherical, with cleavage areas between the tumour and the mastoid external cortex. Surgical excision was performed on cosmetic grounds. Postoperative period was uneventful. Discussion Osteoma over the mastoid region is rare and mainly asymptomatic with excellent prognosis after complete removal of the lesion.

MORPHOLOGICAL GROUNDS FOR PLASTIC SURGERY IN THE MASTOID AREA

This article presents the data on the structural peculiarities of the mastoid region, the dependency between the thickness of the epidermis, dermis, subcutaneous fat, and size of the structural elements of the skin at various stages of its deformation that allows us to determine the digital indices for the depth of skin peeling and skin amount dissected when planning plastic and reconstructive operations skin that is carved. In order to achieve the optimal result of plastic operations, and, in particularly, of cosmetic otoplasty and lower rhytidectomy, and to minimize the development of postoperative complications, the manual skills of the surgeon are not sufficient. It is essential to know exactly morphofunctional characteristics of layered structure of certain topographic and anatomical sites, especially within mastoid area, where the main incisions are made when performing on the above-mentioned surgical interventions. After stretching the test samples of the skin taken from the mastoid region within 5 mm, we observed subtle differences between them even in the state of physiological rest. The study of the structure of the skin-fat flap samples after stretching within 15 mm demonstrated the occurrence of pathological processes in the skin epithelium and dermis. The morphological picture indicated the development of balloon dystrophy that is known as the morphological equivalent of focal necrosis. Investigation of microslides of the skin taken from and exposed to stretching within 20 mm made it possible to reveal the intensification of the previously described changes and the development of qualitatively new pathological changes both in the epidermis and in the dermis. The results obtained enable us to conclude that during operations in the mastoid area, the biomechanical properties of the skin-fat flaps should be taken into account. When the skin was stretched within 5 – 10 mm, irreversible changes did not occur, and these are optimal indicators during surgical interventions. With a flap deformation within 15-20 mm, pathological changes were observed, in some cases they were classified as irreversible that led to necrosis in the postoperative period.