Herculano-Houzel et al. (2015) estimated the number of neurons in different parts of the human brain and spinal cord
A neuron is the basic functional unit of the nervous system
Three types of synapses in the central nervous system (CNS) are: axodendritic, axosomatic, and axoaxonic
Diagram of the autonomic nervous system
Difference between a normal brain and a brain with hydrocephalus: hydrocephalus is an abnormal accumulation of fluid in the brain causing enlargement and developmental problems
Arrows on a woman's body indicate the three major body planes: sagittal, frontal, and transverse; x-axis is the horizontal plane, y-axis is the vertical plane, and z-axis is the sagittal plane
Diagram of the adult human brain showing the forebrain, midbrain, and hindbrain divisions and their functions
Cross-section of the human brain
Human brain image with the left temporal lobe highlighted in red
Group of doctors performingsurgery
Biopsychology is the study of the relationship between biological makeup and psychological functioning, helping understand personality, abnormal behaviors, reactions to stress, and therapy effectiveness
Biopsychology is also known as psychophysiology, physiological psychology, or behavioral neuroscience
Biopsychology aims to relate biology to psychology, explaining behavior through physiological, evolutionary, and functional perspectives
Biopsychology integrates knowledge from neuroscientific disciplines like neuroanatomy, neurochemistry, neuroendocrinology, neuropathology, and neuropharmacology
Human and non-human subjects are used in biopsychological experiments, with advantages and considerations for each
Experiments in biopsychology study cause and effect, with different designs like between subjects, within subject, and quasi-experimental studies
Pure research in biopsychology is driven by curiosity, while applied research aims to bring direct benefits to humanity
Physiological psychology directly manipulates the brain in controlled experiments to study neural mechanisms of behavior using surgical and electrical methods
The adult human brain has three main divisions: the forebrain, midbrain, and hindbrain
The forebrain is the largest part of the brain and contains the cerebral hemispheres, responsible for higher functions like thinking, reasoning, and language
The midbrain connects the forebrain to the hindbrain and is responsible for visual and auditory processing
The hindbrain, the most posterior part of the brain, contains the cerebellum responsible for coordination and balance
Neuropsychology focuses on the psychological effects of brain damage on human patients through case studies and quasi-experimental studies
Psychophysiology studies the relation between physiological activity and psychological processes in human subjects through non-invasive procedures like EEG, muscle tension, and eye movement
Cognitive neuroscience studies the neural bases of cognition, focusing on higher intellectual processes like thought, memory, attention, and complex perceptual processes
Comparative psychology deals with the biology of behavior, comparing different species to understand evolution, genetics, and adaptiveness of behavior
Biopsychologists work together through converging operations, combining different approaches to focus on a single problem, compensating for each other's strengths and weaknesses
Scientific inference is used by biopsychologists to study unobservable processes by characterizing them through empirical methods
The cell of the nervous system consists of neurons and glia, with the blood-brain barrier excluding most chemicals from the brain
Neurons receive and transmit information to other cells, specialized for transmitting information in the nervous system
The structure of an animal cell includes the membrane, protein channels, nucleus, mitochondria, ribosomes, and endoplasmic reticulum
Motor neurons receive excitation through dendrites and conduct impulses along the axon to muscles, responsible for movements and data collection from the brain to be enacted by the body
Sensory neurons are highly sensitive to specific types of stimulation like light, sound, or touch, specialized for senses and coordination
The structure of a neuron includes dendrites with synaptic receptors, a cell body containing the nucleus, and an axon conveying impulses towards other neurons or organs
The axon hillock pushes chemical messengers to travel from one neuron to another, like a gun trigger
The myelin sheath covers axons, speeding up transmission and serving as protection, insulator, and nourishment
Presynaptic terminals release chemicals that cross the junction between neurons, aiding in synaptic transmission
Synapses are junctions between the axon of a neuron and a dendrite of another neuron, facilitating synaptic transmission
Efferent neurons carry information away from a structure, with every motor neuron being an efferent from the nervous system
A major goal of biopsychologists is to characterize unobservable processes by which the nervous system controls behavior through scientific inference