The development of psychology as an empirical science has revolutionized our understanding of human behavior and mental processes. Over the years, psychologists have employed various research methods and measurements to delve deeper into the complexities of the human mind. This multidisciplinary field encompasses several major sub fields, each focusing on different aspects of human behavior, cognition, and emotion.

The study of lifespan development encompasses an exploration of various methods and addresses a range of issues. It involves investigating theories that seek to understand the intricate processes and transformations individuals experience throughout their lives. This unit delves into prenatal development and the challenges faced by newborns, delving further into the formative years of infancy and childhood. The exploration continues into the complexities of adolescence, where the transition from childhood to adulthood occurs. Finally, the study of lifespan development extends into adulthood and aging, examining the unique characteristics and changes that accompany different life stages, ultimately contributing to a comprehensive understanding of the human experience from conception to later years.

In the field of psychology, learning encompasses various processes, including classical conditioning, operant conditioning, and observational and cognitive learning. These different forms of learning play crucial roles in understanding human behavior and the ways in which individuals acquire new behaviors and adapt to their environments.

In this unit, we explore the intricate workings of the nervous system in both human and non-human animals, delving into its complex structure and fascinating functions. Additionally, we examine the endocrine system, uncovering its vital role in regulating various bodily processes through the release of hormones. Furthermore, we investigate the profound interaction between biological factors and experience, acknowledging how our genetics and environment shape our development and behavior. Lastly, we address the methods and issues surrounding biological advances, considering the ethical implications and societal impact of breakthroughs in scientific understanding and technological innovation.

The relationship between conscious and unconscious processes is a fascinating aspect of human cognition. Sleep and dreaming are characterized by distinct patterns of brain activity and bodily relaxation. Psychoactive drugs alter consciousness and have diverse effects on perception, mood, cognition, and behavior. Exploring these states of consciousness provides insights into the complexity of the human mind.

Memory encoding, storage, and retrieval are crucial processes that facilitate the acquisition, retention, and retrieval of information in the human brain. Together, these three interconnected processes enable the human mind to navigate and interact with the world, forming the foundation for our cognitive abilities.

Perspectives on abnormal behavior involve categorizing psychological disorders and employing various treatment approaches. Categories of disorders guide diagnosis and understanding, while perspectives on treatment include psychotherapy, medication, and behavioral interventions.

Social cognition, social influence, and social relations are integral components of human social interactions.  Together, these concepts shed light on the intricate dynamics of human social behavior, highlighting the importance of cognitive processes, external influences, and interpersonal connections in shaping our social lives.