The Behavioral Geography of the Brain Chapter 2
Brain Pathology and Psychological Functions Remember… Any given behavior is the product of a myriad of complex neurophysiological and biochemical interactions involving the whole brain
The Structure of the Brain The Human Brain Cerebral Hemisphere Cerebellum Brain Stem
Cerebral Hemispheres Cerebral hemispheres constitutes the largest part of the human brain. The cerebral hemispheres contain the parts of the brain that evolved most recently– and thus are involved in behaviors of particular interest to clinical neuropsychologists.
The Four Lobes Named after the bones of the skull that cover them Frontal lobe Parietal lobe Temporal lobe Occipital lobe
The Frontal Lobes The front portion of the cerebral cortex, including Broca’s speech area (controls language expression, directs the muscle movements involved in speech) and the motor cortex; damage impairs movement, planning, and flexibility in behavioral strategies
Frontal Lobes
Parietal Lobe The region of the cerebral cortex behind the frontal lobe and above the temporal lobe. The parietal lobes can be divided into two functional regions. 1. Involves sensation and perception 2. Integrating sensory input, primarily with the visual system. The first function integrates sensory information to form a single perception (cognition). The second function constructs a spatial coordinate system to represent the world around us.
Parietal Lobe
Occipital Lobe The rearmost portion of the cerebral cortex; contains the primary visual cortex The Peristriate region of the occipital lobe is involved in visual-spatial processing, discrimination of movement and color discrimination
Occipital Lobe
Temporal Lobe The temporal lobes include both the hippocampus and amygdala as well as our receptive speech centre Wernicke’s area Found in the left temporal lobe, the Wernicke’s area controls language reception. This area is involved in language comprehensions and expression.
Temporal lobe
Lateralization of Function Although the two cerebral hemispheres cooperate with each other, they do not perform identical functions. Some functions are LATERALIZED – located primarily on one side of the brain
Left Hemisphere Participates in the analysis of information The extraction of the elements that make up the whole experience. This ability makes the left hemisphere good at recognizing serial events– events whose elements occur one after the other…
Left Hemisphere Talking Comprehension Reading Writing
Right Hemisphere Specialized for synthesis; it is good at putting isolated elements together to perceive things as a whole (e.g., our ability to draw sketches like a three-dimensional object)
Right Hemisphere Read Maps Navigation Construct complex objects
Left Hemispheric damage of the Parietal lobe Damage to the left Hemisphere can disrupt the ability of a person to draw (can’t make precise hand movements); drawings look shaky and sloppy. Drawing by patient with left hemisphere parietal damage
Right Hemispheric damage of the Parietal lobe Damage to the right parietal lobe impairs a persons ability to pay attention to stimuli located toward the opposite (left) side of the body. Drawing by patient with right parietal lobe damage
Primary Motor Cortex The motor cortex sends messages out to the body When specific parts of this region in the left or right hemispheres are stimulated, specific body parts moved on the opposite side of the body.
Sensory Cortex This cortical area receives information from the skin senses and the movement of body parts. The more sensitive a body region the greater the cortical area devoted to it.
Prefrontal Cortex Deficits Slowing of thoughts and behaviour Loss of spontaneity Perseveration Loss of self-awareness Changes in emotional reactions Deficiencies in foresight and planning Inappropriateness, jocular, disinhibited.
Loss of Self-Awareness Indifferent to events that would normally be expected to affect them emotionally. For example, they may show no signs of distress at the death of a close relative.
Deficits in Foresight and Planning When people’s frontal lobes are damaged, they often do or say things that have unfavorable consequences because they have lost their ability to plan their actions.