When you lie down and the world around you quiets, you may occasionally become aware of a rhythmic whooshing, thumping, or pulsing sound in your ears. This sensation is often described as hearing your own heartbeat. The sound is not imagined but a real auditory experience that originates from processes within your body, usually related to blood flow near the structures of the ear. While frequently harmless, understanding the nature of this sound and its physical mechanisms can help address the concern it often raises.
Defining Pulsatile Tinnitus
The sensation of hearing a rhythmic sound in the ear synchronized with the heart rate is medically termed pulsatile tinnitus. This condition is distinct from common forms of tinnitus, which typically involve continuous sounds like ringing, buzzing, or static noise. In pulsatile tinnitus, the sound is described as a throbbing, swooshing, or whooshing that matches the rhythm of a person’s pulse.
The sound is considered objective because it originates from a physical, detectable source within the body, such as blood vessels. The ear picks up somatic noise—sounds created by normal or altered blood circulation close to the auditory structures. When the sound in your ear quickens or slows at the same time as your pulse, this confirms the vascular origin of the noise.
The Influence of Posture and Blood Flow
The experience of this pulsing sound often becoming louder or more noticeable specifically when lying down is a direct consequence of changes in blood flow dynamics. When the body shifts from an upright to a horizontal position, gravity no longer assists in draining blood from the head and neck. This positional change naturally leads to an increase in blood volume and pressure within the veins and arteries of the head.
The major blood vessels, like the jugular vein and carotid artery, run in close proximity to the middle and inner ear structures. As blood flow velocity or volume increases in these vessels when lying flat, any existing turbulence becomes more pronounced.
This heightened, turbulent blood flow generates louder vibrations that are more readily conducted to the inner ear, making the sound more audible. Furthermore, the silence of a quiet environment removes external sounds that would normally mask this internal noise.
Common Underlying Causes
Pulsatile tinnitus can be a symptom of various conditions that change blood flow or alter the ear’s ability to hear internal sounds. Vascular issues are frequent causes, often creating turbulent flow that the ear detects. For example, high blood pressure (hypertension) forces blood through arteries with greater force, increasing noise. Atherosclerosis, the buildup of plaque that narrows blood vessels, also causes blood to rush through a tighter channel, creating a more audible whooshing sound.
Other vascular conditions involve structural abnormalities near the ear, such as narrowing in the venous drainage system or arteriovenous malformations (abnormal connections between arteries and veins). These malformations can create a loud, turbulent flow that is easily transmitted to the ear.
Conductive hearing issues can also play a role by amplifying normal internal body sounds. Obstruction from excessive earwax or fluid buildup in the middle ear can lead to slight hearing loss, which makes a person more aware of sounds originating within their own body.
Systemic conditions affecting the body’s circulation can also lead to pulsatile tinnitus. Conditions like severe anemia or an overactive thyroid gland (hyperthyroidism) increase the overall speed and volume of blood flow (cardiac output). This generalized increase in flow makes the circulatory noise louder. In some cases, the cause is related to increased pressure around the brain, such as an elevation in intracranial pressure, which affects the flow in the veins draining blood from the head.
Seeking Medical Evaluation
Because pulsatile tinnitus has a physical origin, a medical evaluation is necessary to identify the specific cause and rule out serious underlying conditions. A healthcare professional, often an ear, nose, and throat specialist (otolaryngologist), will begin with a thorough history and physical examination. During the exam, the doctor may listen with a stethoscope to the neck and head to determine if the sound is audible to them, classifying it as objective pulsatile tinnitus.
It is important to seek an evaluation if the sound is sudden in onset, occurs only in one ear, or is accompanied by other symptoms like dizziness, pain, or changes in hearing. The diagnostic process frequently involves specialized tests, including a hearing test (audiogram) to check for conductive issues.
Further investigation often requires imaging studies to visualize the blood vessels and surrounding structures of the head and neck:
- Magnetic Resonance Imaging (MRI)
- Computed Tomography (CT) scans
- Vascular studies (MRA/CTA)
Identifying the precise cause is the first step, as successful management relies on treating the specific condition generating the sound.