Dissociation of Exact and Approximate Calculation in Severe Global Aphasia

The Analysis of Semantic Field in Persian-Speaking Patients With Wernicke’s Aphasia

Objectives: Wernicke’s aphasia is one of the most prominent focal brain deficits affecting the comprehension abilities of patients while preserving their production abilities. Although a lot of studies in different languages have been conducted to analyze the nature of this deficit, still some controversies exist in this regard. While some research studies attribute this defect to a performance...

Correlation between Brain Lesion Site and Fluent/Non-Fluent Aphasia

 Background and purpose: Aphasia is the most common communication disorder resulting from stroke. In this condition all modalities of language, including reading, writing, auditory perception, and oral speech may be affected. Aphasia is divided into two categories: fluent (Wernicke's aphasia, Transcortical sensory aphasia, conduction aphasia, and anomic aphasia) and non-fluent (Broca's aphasia,...

Two mental calculation systems: a case study of severe acalculia with preserved approximation.

We report the case of an aphasic and acalculic patient with selective preservation of approximation abilities. The patient's deficit was so severe that he judged 2 + 2 = 5 to be correct, illustrating a radical impairment in exact calculation. However, he easily rejected grossly false additions such as 2 + 2 = 9, therefore demonstrating a preserved knowledge of the approximate result. The dissoc...

Numerical Study of Non - Equilibrium Air Dissociation For Calculation of Electron Density in Hypersonic Flow

Using an Efficient Penalty Method for Solving Linear Least Square Problem with Nonlinear Constraints

In this paper, we use a penalty method for solving the linear least squares problem with nonlinear constraints. In each iteration of penalty methods for solving the problem, the calculation of projected Hessian matrix is required. Given that the objective function is linear least squares, projected Hessian matrix of the penalty function consists of two parts that the exact amount of a part of i...