Lecture 6 Flashcards
What is the thalamus?
-the large, two-lobed structure that constitutes the top of the brainstem
-forebrain structure that receives signals from sensory receptors, processes them, and then transmits them to the appropriate areas of the sensory cortex
-is an important relay station in the visual, auditory, and somatosensory systems
What is the hypothalamus?
-forebrain structure that is located just below the anterior thalamus
-plays an important role in the regulation of several motivated behaviours (sleep, eating, sexual behaviour)
-on the basis of studies of decorticate animals, Bard concluded that this forebrain structure is critical for the expression of aggressive responses
-regulates body temperature, blood pressure, fluid balance, and concentrations of glucose and sodium
-exerts its effects in part by regulating the release of hormones from the pitutiary gland, which dangles from the ventral surface of the forebrain
What is the cerebral cortex?
-forebrain structure that is a layer of tissue that covers the cerebral hemispheres
-ofter referred to as the gray matter because it is mainly composed of small, unmyelinated neurons which give it a gray appearance
-deeply convoluted in humans
-provides landmarks for locating the four lobes of the cerebral cortex
-on the basis of studies of decorticate animals, Bard concluded that the function of this forebrain structure is to inhibit and direct agressive responses
-while the behavioural and psychological expression of emotional states is dependant on the limbic system, the conscious experience of emotional states is also dependant on this forebrain structure
What is the frontal lobe?
-lobe involved in motor functions and complex cognitive functions, such as planning and evaluating potential behaviour patterns
What is the parietal lobe
Involved in analyzing sensations from the body, perceiving the location of both objects and our own bodies, and in directing our attention
What is the temporal lobe?
-lobe involved in hearing and language, identifying complex visual patterns, and memory
What is the occipital lobe?
-lobe involved in analyzing visual input to guide our behaviour
What is the limbic system?
-system of midline structures that is involved in integrating such vast processes as learning, memory, emotion, and motivation
-system that contains several forebrain structures, including the amygdala, hippocampus, and cingulate cortex
What is the hippocampus?
-forebrain structure that is located in the medial temporal lobe and plays a major role in some kinds of memory, particularly memory for spatial location
-involved in a rat learning to avoid a distinctive chamber where it was previously shocked (contextual fear conditioning) but not in learning to avoid a tone that was paired with the shock (avoidance conditioning
What is the amygdala?
-forebrain structure that is an almond-shaped nucleus in the anterior temporal lobe
-lesions to this forebrain structure block fear conditioning
-receives input from all sensory systems and is believed to be the structure in which the emotional significance of sensory signals is learned and retained
-involved in only some aspects of human fear; e.g., more in the perception of fear in others than the experience of fear
What is the mesolimbic pathway?
-the one of two dopaminergic pathways in the brain that is most implicated in the rewarding effects of brain stimulation, natural rewards, and addictive drugs
-lesions of this pathway tend to disrupt intracarnial self-stimulation
What is the basal ganglia?
-system of midline structures that is involved in the performance of voluntary motor responses, action selection, and switching between motor behaviours
-contains several forebrain structures, including the amygdala, caudate, putamen, and globus pallidus
-contains the striatum (caudate and putamen), which receives input from the rest of the brain, and the globus pallidus, which sends output to the motor cortex
-parkinsons disease is associated with deterioration of the pathway projection from the substantia nigra of the midbrain to this system
What is the primary motor cortex?
-area of cortex within the frontal lobe that is the major point of departure for motor signals descending from the cerebral cortex into lower levels of the sensorimotor system
-contains sites controlling the movements of individual body parts
-is most dedicated to controlling parts of the body that are capable of intricate movements, such as the hands and mouth
What is the primary sensory cortex?
-any area of cortex that receives most of its input directly from the thalamic relay nuclei of one sensory system
-type of cortex that includes the somatosensory cortex, which contains sites that receive sensations from individual body parts
-includes the visual cortex and auditory cortex, which directly receive input from the thalamus for their respective sensory modalities
What is the association cortex?
-any area of cortex that receives input from more than one sensory system
-type of cortex that is at the top of the sensorimotor hierarchy; involved in the highest level of sensory processing that might ultimately result in the performance of movements
