AMYGDALA and SEPTAL AREA

Amygdala:

• Predominant function: ___ center

• Stimulation: ___

• Lesion: ___, ___, hypersexuality

Amygdala:

• Predominant function: AVERSION center

• Stimulation: FEAR

• Lesion: PLACIDITY, HYPERORALITY, hypersexuality

Nucleus accumbens:

• Predominant function: ___ center

• Stimulation: ___ and ___

• Lesion: ___ and ___ behavior

Nucleus accumbens:

• Predominant function: GRATIFICATION center

• Stimulation: JOY and PLEASURE

• Lesion: ADDICTION and IMPULSE behavior

Nucleus accumbens:

• Principal neurotransmitter:

Nucleus accumbens:

• Principal neurotransmitter: dopamine

Amygdala:

• Gray matter structure in anterior and medial aspect of ___ lobe

• Merges with ___ cortex (part of uncus)

Amygdala:

• Gray matter structure in anterior and medial aspect of TEMPORAL lobe

• Merges with PERIAMYGDALOID cortex (part of uncus)

Amygdala:

• Function: emotional responses of ___

Amygdala:

• Function: emotional responses of FEAR

Amygdala:

• 3 nuclear groups:

  • Medial: ___ (adjacent to periamygdaloid cortex)

  • Central: emotional responses

    • Receiving information from the ___ and ___ ___

  • Basolateral: emotional responses

    • Receiving information from the ___ and ___ nuclei

    • Largest nuclear group

Amygdala:

• 3 nuclear groups:

  • Medial: olfaction (adjacent to periamygdaloid cortex)

  • Central: emotional responses

    • Receiving information from the HYPOTHALAMUS and PERIAQUEDUCTAL GRAY

  • Basolateral: emotional responses

    • Receiving information from the CORTEX and CENTRAL nuclei

    • Largest nuclear group

Amygdala: two main pathways

• Stria ___: the long way around

• ___ ___ pathway: the short cut

Amygdala: two main pathways

• Stria TERMINALIS: the long way around

• VENTRAL AMYGDALOFUGAL pathway: the short cut

Amygdala fiber pathways:

• Stria terminalis: from ___ and ___ nuclei

• Ventral amygdalofugal pathway: from ___, ___, ___ and anterior ___ cortex

Amygdala fiber pathways:

• Stria terminalis: from HYPOTHALAMUS and SEPTAL nuclei

• Ventral amygdalofugal pathway: from THALAMUS, HYPOTHALAMUS, ORBITAL and anterior CINGULATE cortex

Amygdala afferents:

• All ___ association areas have direct input to the ___ nucleus

• All association areas are linked to the ___ cortex via association fibers so sensations can be ___ evaluated

Amygdala afferents:

• All SENSORY association areas have direct input to the BASOLATERAL nucleus

• All association areas are linked to the PREFRONTAL cortex via association fibers so sensations can be COGNITIVELY evaluated

Amygdala afferents:

• Visual areas: ___ and ___ states

Amygdala afferents:

• Visual areas: PHOBIAS and ANXIETY states

Amygdala afferents: basolateral (lateral) nucleus

• Lateral geniculate nucleus (visual)

• Cortical source: ___ lobe

Amygdala afferents: basolateral (lateral) nucleus

• Lateral geniculate nucleus (visual)

• Cortical source: OCCIPITAL lobe

Amygdala afferents: basolateral (lateral) nucleus

• Median geniculate nucleus (auditory)

• Cortical source: ___ ___ gyrus

Amygdala afferents: basolateral (lateral) nucleus

• Median geniculate nucleus (auditory)

• Cortical source: SUPERIOR TEMPORAL gyrus

Amygdala afferents: basolateral (lateral) nucleus

• VPN (tactile sensations)

• Cortical source: ___ lobe

Amygdala afferents: basolateral (lateral) nucleus

• VPN (tactile sensations)

• Cortical source: PARIETAL lobe

Amygdala afferents: basolateral (lateral) nucleus

• Locus ceruleus (attention)

• Cortical source: ___ nucleus of ___

Amygdala afferents: basolateral (lateral) nucleus

• Locus ceruleus (attention)

• Cortical source: BASAL nucleus of MEYNERT

Amygdala afferents: basolateral (lateral) nucleus

• ___ nucleus (viscerosensory)

Amygdala afferents: basolateral (lateral) nucleus

• SOLITARY nucleus (viscerosensory)

Amygdala afferents:

• General sense of emotional and physical discomfort from the ___ and ___ cortex

Amygdala afferents:

• General sense of emotional and physical discomfort from the ORBITAL and CINGULATE cortex

Amygdala afferents:

• Visceral sensory from ___ (___ and other sites like the hypothalamus)

Amygdala afferents:

• Visceral sensory from BRAINSTEM (PAG and other sites like the hypothalamus)

Amygdala afferents:

• Visual association cortex (vision, taste, hearing, somatosensory) from ___ and ___

Amygdala afferents:

• Visual association cortex (vision, taste, hearing, somatosensory) from CORTEX and THALAMUS

Amygdala afferents:

• Olfaction from ___ ___ and ___

Amygdala afferents:

• Olfaction from OLFACTORY BULB and CORTEX

Amygdala efferent: stria terminalis

• Emerges from ___ nucleus and follows curve of ___

• Fibers go to ___ area and ___, then to the ___ ___ bundle and central ___ tract

Amygdala efferent: stria terminalis

• Emerges from CENTRAL nucleus and follows curve of CAUDATE

• Fibers go to SEPTAL area and HYPOTHALAMUS, then to the MEDIAL FOREBRAIN bundle and central TEGMENTAL tract

Amygdala efferent: stria terminalis

• ___ nucleus of stria terminalis is regarded as the “extended amygdala” and may be more active than amygdala in ___

Amygdala efferent: stria terminalis

• BED nucleus of stria terminalis is regarded as the “extended amygdala” and may be more active than amygdala in ANXIETY

The ___ nucleus is considered the fear based center.

The BED nucleus is considered the fear based center.

The bed nucleus is between the ___, ___ commissure, and ___ limb of the internal capsule.

The bed nucleus is between the FORNIX, ANTERIOR commissure, and ANTERIOR limb of the internal capsule.

Amygdala efferent: ventral amygdalofugal pathway

• Can end in the:

  • ___/___ cortex (decision making)

  • ___ ___

• Also synapses with nucleus ___

Amygdala efferent: ventral amygdalofugal pathway

• Can end in the:

  • ORBITOFRONTAL/PREFRONTAL cortex (decision making)

  • PERIAQUEDUCTAL GRAY

• Also synapses with nucleus ACCUMBENS

Amygdala efferents:

• Target nucleus/pathway: periaqueductal gray (to medulla/raphespinal tract)

• Function/effect: ___

Amygdala efferents:

• Target nucleus/pathway: periaqueductal gray (to medulla/raphespinal tract)

• Function/effect: ANTINOCICEPTION (decrease pain response)

Amygdala efferents:

• Target nucleus/pathway: periaqueductal gray (to medullary reticulospinal tract)

• Function/effect: ___

Amygdala efferents:

• Target nucleus/pathway: periaqueductal gray (to medullary reticulospinal tract)

• Function/effect: FREEZING

Amygdala efferents:

• Target nucleus/pathway: norepinephrine medullary neurons (project to lateral gray horn)

• Function/effect: ___ heart rate, ___ blood pressure

Amygdala efferents:

• Target nucleus/pathway: norepinephrine medullary neurons (project to lateral gray horn)

• Function/effect: INCREASE heart rate, INCREASE blood pressure

Amygdala efferents:

• Target nucleus/pathway: hypothalamus/dorsal nucleus of vagus (hear)

• Function/effect: ___ heart rate, ___

Amygdala efferents:

• Target nucleus/pathway: hypothalamus/dorsal nucleus of vagus (heart)

• Function/effect: DECREASE heart rate, FAINTING

Amygdala efferents:

• Target nucleus/pathway: hypothalamus (release corticotropin RH)

• Function/effect: ___ hormone secretion

Amygdala efferents:

• Target nucleus/pathway: hypothalamus (release corticotropin RH)

• Function/effect: STRESS hormone secretion

Amygdala efferents:

• Target nucleus/pathway: parabrachial nucleus to medullary respiratory nuclei

• Function/effect: ___ (___ attacks)

Amygdala efferents:

• Target nucleus/pathway: parabrachial nucleus to medullary respiratory nuclei

• Function/effect: HYPERVENTILATION (PANIC attacks)

Amygdala efferents:

• Fibers leave the amygdala through ___ ___ and ___ ___ pathway

Amygdala efferents:

• Fibers leave the amygdala through STRIA TERMINALIS and VENTRAL AMYGDALOFUGAL pathway

Amygdala efferents:

• Amygdala output to ___ ___ believed to be a means for drive-related information to influence decisions about movement

Amygdala efferents:

• Amygdala output to VENTRAL STRIATUM believed to be a means for drive-related information to influence decisions about movement

Amygdala efferents:

• Outputs to all ___ ___ areas

Amygdala efferents:

• Outputs to all CORTICAL SENSORY areas

Kluver-Bucy syndrome:

• Bilateral temporal lobe injury involving ___ and ___ gyrus

• Fearless, placid, no emotional reactions - don’t respond or flee from ___ (___ damage)

• Males become ___

• Visual ___

Kluver-Bucy syndrome:

• Bilateral temporal lobe injury involving AMYGDALA and PARAHIPPOCAMPAL gyrus

• Fearless, placid, no emotional reactions - don’t respond or flee from THREATS (AMYGDALA damage)

• Males become HYPERSEXUAL

• Visal AGNOSIA

Nucleus accumbens is also known as ___ ___.

Nucleus accumbens is also known as VENTRAL STRIATUM.

Nucleus accumbens (ventral striatum):

• Area of fusion of the ___ and head of the ___ nucleus

• Plays an important role in behavior related to ___

Nucleus accumbens (ventral striatum):

• Area of fusion of the PUTAMEN and head of the CAUDATE nucleus

• Plays an important role in behavior related to ADDICTION

Nucleus accumbens (ventral striatum):

• Electrode stimulation induces an intense sense of ___-___

• Comparable to a “high” feeling due to ___ flooding the nucleus accumbens and medial prefrontal cortex from ___ ___ area in the midbrain

Nucleus accumbens (ventral striatum):

• Electrode stimulation induces an intense sense of WELL-BEING

• Comparable to a “high” feeling due to DOPAMINE flooding the nucleus accumbens and medial prefrontal cortex from VENTRAL TEGMENTAL area in the midbrain

Nucleus accumbens (ventral striatum):

• Comparable to a “high” feeling due to dopamine flooding the nucleus accumbens and medial prefrontal cortex from the ventral tegmental area in the midbrain:

  • ___ fibers: from midbrain to nucleus accumbens

  • ___ fibers: from midbrain to medial prefrontal cortex

Nucleus accumbens (ventral striatum):

• Comparable to a “high” feeling due to dopamine flooding the nucleus accumbens and medial prefrontal cortex from the ventral tegmental area in the midbrain

  • MESOLIMBIC fibers: from midbrain to nucleus accumbens

  • MESOCORTICAL fibers: from midbrain to medial prefrontal cortex

Basal ganglia circuits:

• Goal: modulate cortical ___

• Cortical start and end points determine loop ___

• Cerebral cortex —> ___ —> ___ —> ___ nuclei

Basal ganglia circuits:

• Goal: modulate cortical OUTPUT

• Cortical start and end points determine loop FUNCTION

• Cerebral cortex —> STRIATUM —> PALLIDUM —> THALAMIC nuclei

Limbic loop in basal ganglia:

• Drive-related information can influence decisions about ___ and ___

  • Associate stimuli with rewards

• If something is pleasurable, it increases ___ ___ dopamine release from ___ ___ area in the midbrain

Limbic loop in basal ganglia:

• Drive-related information can influence decisions about MOVEMENT and BEHAVIORS

  • Associate stimuli with rewards

• If something is pleasurable, it increases VENTRAL STRIATAL (nucleus accumbens) dopamine release from VENTRAL TEGMENTAL area in the midbrain

Limbic loop in basal ganglia:

• Ventral pallidum is an extension of ___ ___

Limbic loop in basal ganglia:

• Ventral pallidum is an extension of GLOBUS PALLIDUS

Septal area/nuclei:

• Septal nuclei merge with cortex, anterior to ___ ___ and a small extension to ___ ___

Septal area/nuclei:

• Septal nuclei merge with cortex, anterior to ANTERIOR COMMISSURE and a small extension to SEPTUM PELLUCIDUM

Septal nuclei: afferents

• ___, via the diagonal band of Broca

• ___ tract, via the medial olfactory stria

• ___, via the fornix

• ___ ___, via medial forebrain bundle

Septal nuclei: afferents:

• AMYGDALA, via the diagonal band of Broca

• OLFACTORY tract, via the medial olfactory stria

• HIPPOCAMPUS, via the fornix

• BRAINSTEM MONOAMINES, via the medial forebrain bundle

Septal nuclei: efferents:

• 2 major efferent projections:

  • ___ ___ to epithalamus

    • Strip of white matter near roof of third ventricle

    • Interconnects habenular nucleus and interpeduncular nucleus of midbrain reticular formation via habenulointerpeduncular tract

    • Important in ___-___ cycle

  • ___ pathway to hippocampus

Septal nuclei: efferents

• 2 major efferent projections:

  • STRIA MEDULLARIS to epithalamus

    • Strip of white matter near roof of third ventricle

    • Interconnects habenular nucleus and interpeduncular nucleus of medbrain reticular formation via habenulointerpeduncular tract

    • Important in SLEEP-WAKE cycle

  • SEPTOHIPPOCAMPAL pathway to hippocampus

Septal nuclei: efferents

• ___ pathway travels in fornix

  • ___ neurons

  • Produces theta rhythm important in hippocampal function during long-term ___ in episodic memory

  • Greatly reduced in Alzheimer disease

    • Loss of ___ neurons —> issues with episodic memory formation and retrieval

Septal nuclei: efferents

• SEPTOHIPPOCAMPAL pathway travels in fornix

  • CHOLINERGIC neurons

  • Produces theta rhythm important in hippocampal function during long-term POTENTIATION in episodic memory

  • Greatly reduced in Alzheimer disease

    • Loss of CHOLINERGIC neurons —> issues with episodic memory formation and retrieval

Basal forebrain:

• Extends from:

  • Bifurcation of ___ tract posteriorly to the ___

  • Midline to the ___

• See ___ ___ substance in floor

  • Perforating branches of Circle of Willis

  • Scattered nuclear groups that contain ___ neurons (___)

    • Largest in basal nucleus of Meynert

Basal forebrain:

• Extends from:

  • Bifurcation of OLFACTORY tract posteriorly to INFUNDIBULUM

  • Midline to the AMYGDALA

• See ANTERIOR PERFORATED substance in floor

  • Perforating branches of Circle of Willis

  • Scattered nuclear groups that contain CHOLINERGIC neurons (ACETYLCHOLINE)

    • Largest in basal nucleus of Meynert

Basal forebrain and septal nuclei:

• Contains ___ neurons (___)

  • Meynert is tonically active while awake

• Supplies all cortical areas, activating cortical neurons by making them more responsive to other ___ inputs

• Supports long-term ___ and synaptic ___

Basal forebrain and septal nuclei:

• Contains CHOLINERGIC neurons (ACETYLCHOLINE)

  • Meynert is tonically active while awake

• Supplies all cortical areas, activating cortical neurons by making them more responsive to other EXCITATORY inputs

• Supports long-term POTENTIATION and synaptic STRENGTHENING

Cholinergic neurons in the forebrain:

• Have ___ cerebral cortex projections

• Impacted in Alzheimer’s disease

  • Drug treatment: cholinesterase inhibitors slow the breakdown of ___

Cholinergic neurons in the forebrain:

• Have DIFFUSE cerebral cortex projections

• Impacted in Alzheimer’s disease

  • Drug treatment: cholinesterase inhibitors slow the breakdown of ACETYLCHOLINE

Cholinergic neurons in the brainstem:

• ___ ___ tegmentum

  • Important in sleep and wakefulness

  • Pedunculopontine nucleus

  • Interpeduncular nucleus

Cholinergic neurons in the brainstem:

• DORSOLATERAL PONTINE tegmentum

  • Important in sleep and wakefulness

  • Pedunculopontine nucleus

  • Interpeduncular nucleus

The limbic loop in the basal ganglia associates stimuli with “___” resulting in increased ___ release.

The limbic loop in the basal ganglia associates stimuli with “REWARD” resulting in increased DOPAMINE release.

The ___ and ___ nuclei of the amygdala are associated with emotional responses.

The CENTRAL and BASOLATERAL nuclei of the amygdala are associated with emotional responses.

The septohippocampal pathway uses the ___ to synapse in the hippocampus.

The septohippocampal pathway uses the FORNIX to synapse in the hippocampus.

The basal forebrain consists of scattered nuclei, containing mostly ___ neurons.

The basal forebrain consists of scattered nuclei, containing mostly CHOLINERGIC neurons.

The ___ ___ is important in hippocampal function during long-term potentiation in episodic memory.

The SEPTAL AREA is important in hippocampal function during long-term potentiation in episodic memory.

The amygdala is located in the ___ lobe.

The amygdala is located in the MESOTEMPORAL lobe.