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Framework for Anatomy and Physiology

Samuel R. Atcherson, Melanie L. Meeker, and Bonnie K. Slavych

■ Chapter Summary

The human body is undeniably complex, yet it works in ways that can be understood in functional "bite-size" units, from micro (biochemical and cellular) to macro (system and body) levels. The study of anatomy and physiology is essential to the understanding of the human body. To fully appreciate a disorder, speech-language pathologists and audiologists must have a working knowledge of how various parts of the body function and how they work together toward a meaningful goal. The purpose of this chapter is to set the stage for the study of anatomy and physiology for speech, language, swallowing, hearing, balance, and related disorders. Specifically, we introduce terminology commonly used in the study of anatomy and physiology; provide an overview of the various body systems, including those used for speech, language, swallowing, hearing, balance, and related functions; and relate these concepts to disorders managed by speech-language pathologists and audiologists.

■ Learning Objectives

 Define and differentiate common terms used in the study of anatomy and physiology

 Understand the functions of the basic tissue and joint types in the human body

 Describe the general functions of the body systems supporting speech, language, swallowing, hearing, balance, and related functions

■ Putting It Into Practice

 Speech-language pathologists and audiologists are the professionals involved in the treatment of speech, language, swallowing, hearing, balance, and related disorders.

 The assessment and management of disorders related to speech, language, swallowing, hearing, and balance require a basic understanding of normal structure and function.

 The study of anatomy and physiology provides an essential framework in the practice of speech-language pathology and audiology.

■ Introduction

The study of human anatomy and physiology provides an important foundation for the speech-language pathologist and audiologist. The basic concepts of anatomy and physiology serve as the essential framework upon which to build an understanding of a variety of human activities. Students approaching the study of anatomy and physiology for the first time are often overwhelmed by the new terminology. Students will encounter many prefixes and suffixes that are used throughout the practice of medicine and related healthcare fields. Many of these roots are Latin or Greek in origin. For example, the prefix "a-" or "an-" is from a Greek word meaning "not" or "without." You may have encountered this prefix in the words atypical (meaning not typical) or anaerobic (meaning without oxygen). An understanding of prefixes and suffixes will facilitate your learning of the material and increase the relevance of these terms to the practice of speech-language pathology and audiology.

A strong foundation in anatomy also provides important information about how the body works. Take the stylohyoid muscle as an example. Its name can be broken down into its component parts: stylo- (referencing the styloid process of the temporal bone) and hyoid (referencing the U-shaped bone above the larynx). The stylohyoid muscle spans the distance between the two structures. Knowing that striated skeletal muscles contract when stimulated, you can deduce that stimulation of this muscle draws the hyoid bone closer to the styloid process. An understanding of where the structures are located then provides information about function, which is to move the hyoid backward (posteriorly) toward the styloid. Although some exceptions to this general rule exist, a basic understanding of the general principles that underlie physiological function will provide a solid foundation upon which to build a conceptual framework.

To facilitate learning, students are encouraged to read assigned materials prior to class and to make purposeful notes in the margins of this text or on study cards. This preparation will allow you to more fully engage in lectures and acquire a deeper understanding of the concepts discussed during class. Consider incorporating a variety of cognitive and physical modalities in your learning. Practice drawing and labeling structures or manipulating them mentally to visualize them from different angles. Recite unfamiliar words aloud and practice their pronunciation. Explore topics of interest by accessing the supplemental materials referenced at the end of each chapter. Use the study questions at the end of each chapter to prepare for exams. These techniques will actively involve and engage aspects of your working memory and help you to organize and store information in your long-term memory for later retrieval (e.g., on an exam or when working with a patient). Mnemonic memory aids (e.g., acronyms or clever phrases) may also be helpful.

This text utilizes a variety of techniques to teach students keys to anatomical exploration and related physiology. The major anatomical systems are presented to familiarize students with the entire body. Glossary terms are bolded throughout the text, and definitions can be found within each chapter and at the end of the book. In addition, each chapter includes clinically relevant text boxes to increase the relevance of key concepts to clinical practice. Finally, a list of suggested readings in each chapter will guide the interested student to more information on the topics in the chapter.

Now that we have set the stage for your exploration of anatomy and physiology, let's begin. Simply stated, anatomy is the study of the structure of an organism. Gross anatomy consists of what can be inspected with the naked eye, such as what might occur in a cadaver lab. Physiology explores the functions of structures in a living organism. Together, the study of anatomy and physiology explores the structure and function of a living organism in terms of its parts and the organism as a whole. Pathology is the study of diseases and the structural and functional changes that affect an organism. This text provides a solid foundation in anatomy and physiology relevant to the practice of speech-language pathology and audiology.

■ Basic Elements of Anatomy

General Anatomical Terms and Anatomical Position

Early anatomists named structures based on what they resembled. As an example, a structure deep within the brain has a curly shape that, upon discovery, was thought to resemble a seahorse, so it was named the hippocampus from the Greek word for that animal. Hippos, "horse," is also found in hippotherapy, which makes use of the rhythmic movements of the horse.

Once you learn to deconstruct the vocabulary of anatomy, you will be on your way to mastery of the material. Table 1.1 provides roots, their meanings, and an example of each root in the context of some commonly used terms in speech-language pathology and audiology.

Terms of Orientation

Used as a reference to describe various body parts relative to one another, the standard posture when in the anatomic position is with your full body standing straight, with the face directed forward, the arms hanging down at your sides with your palms facing forward, fingers pointing straight down, and the knees facing forward with the feet slightly apart and pointed forward. Anatomic position is important as it is the assumed position of reference when using directional terms to describe position or direction of body structures. Anatomic position is shown in Fig. 1.1.

Fig. 1.1 Anatomic position. Anterior view. From Schünke M, Schulte E, Schumacher U, THIEME Atlas of Anatomy, General Anatomy and Musculoskeletal System. Thieme 2014. Illustration by Markus Voll.

Just as the directional terms north, east, south, and west serve as a reference on a compass (or GPS system), directional terms are commonly used to orient to a specific area of the body. Perhaps the most commonly used terms are superior, inferior, anterior, and posterior. These terms tell you the position of a point of interest in the body relative to some other body part. When something is superior, it is above or higher than another structure; when inferior, it is below or under; when anterior, it is in front; and when posterior, it is behind or in back of another structure (see Fig. 1.1). For example, the head is superior to the neck, the ankle is inferior to the knee, the spine is posterior to the heart, and the sternum (breastbone) is anterior to the spine.

Other commonly used directional terms include dorsal, ventral, rostral, caudal, superficial, and deep. Dorsal refers to the posterior surface (as in a dolphin's dorsal fin) and ventral refers to the anterior surface (toward the belly). Rostral means toward the nose, while caudal indicates toward the tail. (A speaker's platform is called a rostrum after the Rostra in the ancient Roman Forum, which was decorated with the rams from the bow ends of captured warships.) The term superficial indicates toward the surface, while deep references away from a surface. Putting...